anchor_id
stringlengths 8
8
| anchor_title
stringlengths 22
248
| anchor_abstract
stringlengths 73
4.05k
| positive_pool
listlengths 1
1
| negative_pool
listlengths 1
1
|
|---|---|---|---|---|
22509163
|
Targets for a comparative neurobiology of language.
|
One longstanding impediment to progress in understanding the neural basis of language is the development of model systems that retain language-relevant cognitive behaviors yet permit invasive cellular neuroscience methods. Recent experiments in songbirds suggest that this group may be developed into a powerful animal model, particularly for components of grammatical processing. It remains unknown, however, what a neuroscience of language perception may look like when instantiated at the cellular or network level. Here we deconstruct language perception into a minimal set of cognitive processes necessary to support grammatical processing. We then review the current state of our understanding about the neural mechanisms of these requisite cognitive processes in songbirds. We note where current knowledge is lacking, and suggest how these mechanisms may ultimately combine to support an emergent mechanism capable of processing grammatical structures of differing complexity.</AbstractText
|
[
[
"10378865",
"Neurokinin type-1 receptor antagonist inhibits enhancement of T cell functions by substance P in normal and neuromanipulated capsaicin-treated rats.",
"Substance P (SP) plays a major role in the regulation of the interaction between immune and nervous systems. SP administration stimulates Con A-induced proliferation of spleen and peripheral blood lymphocytes from normal and neonatally capsaicin treated rats, which correlated with enhanced IL-2 production and expression of activation antigens such as IL-2 receptor alpha chain (CD25) and RT1B MHC class II molecule. Moreover, SP markedly increased the percentage of CD5+ and CD4+ T lymphocytes in the peripheral blood of capsaicin-treated rats. Concomitant administration of SP with the non-peptide Neurokinin-1 receptor (NK1R) antagonist SR140333 completely inhibited the SP-mediated augmentation of Con A-induced PBL proliferation and IL-2 production as well as of CD4+ CD25+ and CD4+ RT1B+ T cell numbers in normal and capsaicin-treated rats. SR 140333 also blocked the increased percentage of peripheral blood CD4+ T cells induced by SP in capsaicin-treated rats.</AbstractText"
]
] |
[
[
"23264884",
"Neurogenetics and Epigenetics in Impulsive Behaviour: Impact on Reward Circuitry.",
"Adverse, unfavourable life conditions, particularly during early life stages and infancy, can lead to epigenetic regulation of genes involved in stress-response, behavioral disinhibition, and cognitive-emotional systems. Over time, the ultimate final outcome can be expressed through behaviors bedeviled by problems with impulse control, such as eating disorders, alcoholism, and indiscriminate social behavior. While many reward gene polymorphisms are involved in impulsive behaviors, a polymorphism by itself may not translate to the development of a particular behavioral disorder unless it is impacted by epigenetic effects. Brain-derived neurotrophic factor (BDNF) affects the development and integrity of the noradrenergic, dopaminergic, serotonergic, glutamatergic, and cholinergic neurotransmitter systems, and plasma levels of the neurotrophin are associated with both cognitive and aggressive impulsiveness. Epigenetic mechanisms associated with a multitude of environmental factors, including premature birth, low birth weight, prenatal tobacco exposure, non-intact family, young maternal age at birth of the target child, paternal history of antisocial behavior, and maternal depression, alter the developmental trajectories for several neuropsychiatric disorders. These mechanisms affect brain development and integrity at several levels that determine structure and function in resolving the final behavioral expressions.</AbstractText"
]
] |
23195310
|
Model organism databases in behavioral neuroscience.
|
Model Organism Databases (MODs) are an important informatics tool for researchers. They provide comprehensive organism specific genetic, genomic, and phenotype datasets. MODs ensure accurate data identification and integrity and provide official nomenclature for genes, Quantitative Trait Loci, and strains. Most importantly, the MODs provide professionally curated data drawn from the literature for function, phenotype and disease associations, and pathway involvement. These data, along with nomenclature and data identity, are incorporated into larger scale genomic databases and research publications. MODs also offer a number of software tools that allow researchers to access, display, and analyze data from reports to genome browsers.</AbstractText
|
[
[
"19254758",
"Re-exposure to endotoxin induces differential cytokine gene expression in the rat hypothalamus and spleen.",
"This study was designed to investigate whether the pattern of hypothalamic and splenic cytokine expression induced by peripheral administration of a bacterial lipopolysaccharide (LPS) is affected by prior exposure to LPS derived from another bacterial strain. Injection of LPS from Salmonella enteritidis (LPS(2)) alone resulted in increased hypothalamic gene expression of IL-1beta, IL-6, TNFalpha, IL-1ra and IL-10. However, pre-exposure to LPS derived from Escherichia coli (LPS(1)) 3 weeks before, significantly attenuated hypothalamic IL-1ra, IL-6 and IL-10 expression. IL-1beta expression also tended to be lower. This pattern contrasted with the robust cytokine expression in the spleen of LPS(2)-treated rats previously exposed to LPS(1), since pre-treatment with endotoxin resulted in a significantly greater response of IL-1beta and IL-1ra to LPS(2). Expression of TNFalpha and IL-10 also tended to be higher. Pre-treatment with LPS(1) did not significantly affect the marked increase in corticosterone and adrenaline blood levels induced by LPS(2). Thus, while endotoxin pre-exposure seemed not to induce a \"tolerant\" state in the periphery as judged by the immune and endocrine parameters evaluated upon re-stimulation, expression of four of the six cytokines measured was decreased in the hypothalamus. This is the first demonstration that endotoxin priming can differentially affect cytokine expression in the central nervous system and peripheral tissues when a host is confronted with a second, acute, pro-inflammatory stimulus. These results may provide new evidence for the involvement of cytokine pathways in the central nervous system in modulating peripheral inflammation and mediating cognitive and behavioural alterations during inflammatory diseases.</AbstractText"
]
] |
[
[
"23181017",
"Support vector machines for spike pattern classification with a leaky integrate-and-fire neuron.",
"Spike pattern classification is a key topic in machine learning, computational neuroscience, and electronic device design. Here, we offer a new supervised learning rule based on Support Vector Machines (SVM) to determine the synaptic weights of a leaky integrate-and-fire (LIF) neuron model for spike pattern classification. We compare classification performance between this algorithm and other methods sharing the same conceptual framework. We consider the effect of postsynaptic potential (PSP) kernel dynamics on patterns separability, and we propose an extension of the method to decrease computational load. The algorithm performs well in generalization tasks. We show that the peak value of spike patterns separability depends on a relation between PSP dynamics and spike pattern duration, and we propose a particular kernel that is well-suited for fast computations and electronic implementations.</AbstractText"
]
] |
23372986
|
Experience with multimodality telepathology at the University of Pittsburgh Medical Center.
|
Several modes of telepathology exist including static (store-and-forward), dynamic (live video streaming or robotic microscopy), and hybrid technology involving whole slide imaging (WSI). Telepathology has been employed at the University of Pittsburgh Medical Center (UPMC) for over a decade at local, national, and international sites. All modes of telepathology have been successfully utilized to exploit our institutions subspecialty expertise and to compete for pathology services. This article discusses the experience garnered at UPMC with each of these teleconsultation methods. Static and WSI telepathology systems have been utilized for many years in transplant pathology using a private network and client-server architecture. Only minor clinically significant differences of opinion were documented. In hematopathology, the CellaVision(®) system is used to transmit, via email, static images of blood cells in peripheral blood smears for remote interpretation. While live video streaming has remained the mode of choice for providing immediate adequacy assessment of cytology specimens by telecytology, other methods such as robotic microscopy have been validated and shown to be effective. Robotic telepathology has been extensively used to remotely interpret intra-operative neuropathology consultations (frozen sections). Adoption of newer technology and increased pathologist experience has improved accuracy and deferral rates in teleneuropathology. A digital pathology consultation portal (https://pathconsult.upmc.com/) was recently created at our institution to facilitate digital pathology second opinion consults, especially for WSI. The success of this web-based tool is the ability to handle vendor agnostic, large image files of digitized slides, and ongoing user-friendly customization for clients and teleconsultants. It is evident that the practice of telepathology at our institution has evolved in concert with advances in technology and user experience. Early and continued adoption of telepathology has promoted additional digital pathology resources that are now being leveraged for other clinical, educational, and research purposes.</AbstractText
|
[
[
"3974835",
"Bilateral traumatic abducens nerve palsy without skull fracture and with cervical spine fracture: case report and review of the literature.",
"Bilateral traumatic abducens nerve palsy is a rare condition. Here a case without skull fracture and associated with cervical spine fracture is reported. Only two cases like this were found in a review of the literature. The mechanism of the lesion is discussed in light of the two main theories proposed thus far. When the injury is acute, as happens in the majority of cases, the nerve lesion probably is due to contusion and stretch of the nerve trunk against the ridge of the petrous bone and the rigid dural hole of entrance in the extradural space at the basilar process.</AbstractText"
]
] |
[
[
"23193602",
"Arthropod venoms: a vast arsenal of insecticidal neuropeptides.",
"Arthropods are the most diverse animal group on the planet, and occupy almost all ecological niches. Venomous arthropods are a rich source of bioactive compounds evolved for prey capture and defense against predators and/or microorganisms. These highly potent chemical arsenals represent an available source for new insecticidal compounds as they act selectively on their molecular targets. These toxins affect the invertebrate nervous system and, until the moment, several insecticidal compounds belonging to the class of peptides or polyamine-like compounds have been purified and characterized from the venom of arachnids and hymenopterans. This review focuses on invertebrate-specific peptide neurotoxins that have been isolated from the venom ofspiders, scorpions, centipedes, ants, and wasps, discussing their potential in pest control and as invaluable tools in neuropharmacology.</AbstractText"
]
] |
23060761
|
A computational approach to "free will" constrained by the games we play.
|
Human choice is not free-we are bounded by a multitude of biological constraints. Yet, within the various landscapes we face, we do express choice, preference, and varying degrees of so-called willful behavior. Moreover, it appears that the capacity for choice in humans is variable. Empirical studies aimed at investigating the experience of "free will" will benefit from theoretical disciplines that constrain the language used to frame the relevant issues. The combination of game theory and computational reinforcement learning theory with empirical methods is already beginning to provide valuable insight into the biological variables underlying capacity for choice in humans and how things may go awry in individuals with brain disorders. These disciplines operate within abstract quantitative landscapes, but have successfully been applied to investigate strategic and adaptive human choice guided by formal notions of optimal behavior. Psychiatric illness is an extreme, but interesting arena for studying human capacity for choice. The experiences and behaviors of patients suggest these individuals fundamentally suffer from a diminished capacity of willful choice. Herein, I will briefly discuss recent applications of computationally guided approaches to human choice behavior and the underlying neurobiology. These approaches can be integrated into empirical investigation at multiple temporal scales of analysis including the growing body of experiments in human functional magnetic resonance imaging (fMRI), and newly emerging sub-second electrochemical and electrophysiological measurements in the human brain. These cross-disciplinary approaches hold promise for revealing the underlying neurobiological mechanisms for the variety of choice capacity in humans.</AbstractText
|
[
[
"19400719",
"The science of neural interface systems.",
"The ultimate goal of neural interface research is to create links between the nervous system and the outside world either by stimulating or by recording from neural tissue to treat or assist people with sensory, motor, or other disabilities of neural function. Although electrical stimulation systems have already reached widespread clinical application, neural interfaces that record neural signals to decipher movement intentions are only now beginning to develop into clinically viable systems to help paralyzed people. We begin by reviewing state-of-the-art research and early-stage clinical recording systems and focus on systems that record single-unit action potentials. We then address the potential for neural interface research to enhance basic scientific understanding of brain function by offering unique insights in neural coding and representation, plasticity, brain-behavior relations, and the neurobiology of disease. Finally, we discuss technical and scientific challenges faced by these systems before they are widely adopted by severely motor-disabled patients.</AbstractText"
]
] |
[
[
"24294562",
"Dorello's Canal and Gruber's Ligament: Historical Perspective.",
"Wenzel Leopold Gruber and Primo Dorello were great anatomists and researchers during the 19th and 20th centuries. Their contributions to neuroanatomy-namely the Gruber's (petrosphenoidal) ligament and Dorello's canal, respectively-have come to be important structures in various approaches through the middle fossa. These structures have also helped provide us with an understanding of the mechanism of sixth nerve paresis in various pathological conditions, such as raised intracranial pressure and Gradenigo syndrome. Their numerous publications have stood as a reference to anatomical researchers. Gruber's description of internal mesogastric hernia and the Meckel-Gruber anastomosis are also widely known in medical literature. The following article is an attempt to reflect upon the life and works of Gruber and Dorello and the importance of their research.</AbstractText"
]
] |
23035093
|
Optimization of a GCaMP calcium indicator for neural activity imaging.
|
Genetically encoded calcium indicators (GECIs) are powerful tools for systems neuroscience. Recent efforts in protein engineering have significantly increased the performance of GECIs. The state-of-the art single-wavelength GECI, GCaMP3, has been deployed in a number of model organisms and can reliably detect three or more action potentials in short bursts in several systems in vivo. Through protein structure determination, targeted mutagenesis, high-throughput screening, and a battery of in vitro assays, we have increased the dynamic range of GCaMP3 by severalfold, creating a family of "GCaMP5" sensors. We tested GCaMP5s in several systems: cultured neurons and astrocytes, mouse retina, and in vivo in Caenorhabditis chemosensory neurons, Drosophila larval neuromuscular junction and adult antennal lobe, zebrafish retina and tectum, and mouse visual cortex. Signal-to-noise ratio was improved by at least 2- to 3-fold. In the visual cortex, two GCaMP5 variants detected twice as many visual stimulus-responsive cells as GCaMP3. By combining in vivo imaging with electrophysiology we show that GCaMP5 fluorescence provides a more reliable measure of neuronal activity than its predecessor GCaMP3. GCaMP5 allows more sensitive detection of neural activity in vivo and may find widespread applications for cellular imaging in general.</AbstractText
|
[
[
"19064491",
"Retention of high tactile acuity throughout the life span in blindness.",
"Previous studies of tactile acuity on the fingertip, using passive touch, have demonstrated an age-related decline in spatial resolution for both sighted and blind subjects. We have reexamined this age dependence with two newly designed tactile-acuity charts that require active exploration of the test symbols. One chart used dot patterns similar to braille, and the other used embossed Landolt rings. Groups of blind braille readers and sighted subjects ranging from 12 to 85 years old were tested in two experiments. We replicated previous findings for sighted subjects by showing an age-related decrease in tactile acuity by nearly 1% per year. Surprisingly, the blind subjects retained high acuity into old age, showing no age-related decline. For the blind subjects, tactile acuity did not correlate with braille reading speed, the amount of daily reading, or the age at which braille was learned. We conclude that when measured with active touch, blind subjects retain high tactile acuity into old age, unlike their aging sighted peers. We propose that blind people's use of active touch in daily activities, not specifically braille reading, results in preservation of tactile acuity across the life span.</AbstractText"
]
] |
[
[
"23033443",
"Apraxia of speech: concepts and controversies.",
"This article was written as an editorial to a collection of original articles on apraxia of speech (AOS) in which some of the more recent advancements in the understanding of this syndrome are discussed. It covers controversial issues concerning the theoretical foundations of AOS. Our approach was motivated by a change of perspective on motor speech that has taken place in neurobiology, neurolinguistics, phonology, and phonetics during the past few decades.</AbstractText The literature on AOS is reviewed from 3 different but overlapping perspectives-that is, a disconnection, a motor memory, and a fine motor skill perspective. Separate sections are devoted to the delimitations of AOS from oral facial apraxia, dysarthria, and phonological impairment.</AbstractText We conclude that many of the still unresolved conceptual issues about AOS arise from an underspecification of existing models of spoken language production. We suggest that phonological and motor impairments of sound production should be studied by an integrated approach.</AbstractText"
]
] |
23055482
|
Towards a new neurobiology of language.
|
Theoretical advances in language research and the availability of increasingly high-resolution experimental techniques in the cognitive neurosciences are profoundly changing how we investigate and conceive of the neural basis of speech and language processing. Recent work closely aligns language research with issues at the core of systems neuroscience, ranging from neurophysiological and neuroanatomic characterizations to questions about neural coding. Here we highlight, across different aspects of language processing (perception, production, sign language, meaning construction), new insights and approaches to the neurobiology of language, aiming to describe promising new areas of investigation in which the neurosciences intersect with linguistic research more closely than before. This paper summarizes in brief some of the issues that constitute the background for talks presented in a symposium at the Annual Meeting of the Society for Neuroscience. It is not a comprehensive review of any of the issues that are discussed in the symposium.</AbstractText
|
[
[
"21748284",
"A failure to normalize biochemical and metabolic insults during morphine withdrawal disrupts synaptic repair in mice transgenic for HIV-gp120.",
"Drug abuse in HIV-infected individuals accelerates the onset and progression of HIV-associated neurocognitive disorders (HAND). Opiates are a class of commonly abused drugs that have interactive effects with neurotoxic HIV proteins that facilitate glial dysfunction, neuronal damage and death. While the combined effects of neurotoxic HIV proteins and morphine have been extensively studied in the setting of chronic and acute morphine use, very little in known about the effects of HIV proteins during drug withdrawal. Since opiate withdrawal can induce considerable neuronal stress, we determined the effects of opiates (morphine) on brain redox balance, sphingolipid metabolism and synaptic integrity during both chronic and withdrawal conditions in non-transgenic mice (nTg), and in mice transgenic for the HIV-coat protein gp120 (gp120tg). In nTg mice, we found that chronic morphine increased brain oxidative capacity and induced synaptic damage that was largely reversed during drug withdrawal. Gp120tg mice showed a similar response to chronic morphine, but the diminished oxidative capacity and synaptic damage failed to normalize during drug withdrawal. In nTg mice, brain sphingolipid content was not affected by morphine during chronic or withdrawal conditions. In gp120tg mice there was a baseline perturbation in sphingolipid metabolism that manifest as decreased sphingomyelin with accumulations of the bioactive lipid ceramide. Sphingolipid metabolism was highly reactive to morphine in gp120tg mice. Chronic morphine increased sphingomyelin content with a consequent reduction in ceramide. During drug withdrawal, these effects reversed, and sphingomyelin levels were reduced with consequent increases of ceramide. We interpret these findings to suggest that neuronal repair during morphine withdrawal is inhibited in the setting of gp120 by mechanisms that involve sustained oxidative insult and accumulations of the highly reactive intermediate ceramide.</AbstractText"
]
] |
[
[
"23195316",
"Opportunities for bioinformatics in the classification of behavior and psychiatric disorders.",
"A bioinformatics approach to behavioral neuroscience provides both unique opportunities and challenges for research on behavior. A major challenge has been to describe, define, and discriminate among abstract behavioral processes, in large part by distinguishing among the biological mechanisms of unique but not entirely discrete, entities of behavior. Understanding the complexity of neurobiology and behavior requires integration of data across diverse biological systems, types of data, and levels of scale. With the perspective and application of bioinformatics, we can uncover the relationships among these systems and take steps forward in realizing the common and distinct bases of psychiatric disease.</AbstractText"
]
] |
23505339
|
Baby Steps to Superintelligence: Neuroprosthetics and Children.
|
Children surviving neural injuries face challenges not seen by their adult counterparts, namely that they experience neural injury before reaching neurodevelopmental maturity. Neural prostheses offer one possible path to recovery, along with the potential for functional outcomes that could exceed expectations. Although the first cochlear implant was placed more than fifty years ago, the field of neuroprosthetics is still relatively young. Several types of neural prostheses are in development stages ranging from animal models to (adult) human trials. In this paper, I discuss how neural prostheses may assist recovery for children surviving neural injury. I argue that approaching the use of neural prosthetics in children with considerations derived from transhumanism alongside traditional bioethics can provide an opportunity to reframe adult-focused ethics toward a child/family focus and to strip away the prejudicial metaphor of cyborgization.</AbstractText
|
[
[
"12951145",
"Structure and function of the vomeronasal system: an update.",
"Several developments during the past 15 years have profoundly affected our understanding of the vomeronasal system (VNS) of vertebrates. In the mid 1990s, the vomeronasal epithelium of mammals was found to contain two populations of receptor cells, based on their expression of G-proteins. These two populations of neurons were subsequently found to project their axons to different parts of the accessory olfactory bulb (AOB), forming the basis of segregated pathways with possibly heterogeneous functions. A related discovery was the cloning of members of at least two gene families of putative vomeronasal G-protein-coupled receptors (GPRs) in the vomeronasal epithelium. Ligand binding to these receptors was found to activate a phospholipase C (PLC)-dependent signal transduction pathway that primarily involves an increase in intracellular inositol-tris-phosphate and intracellular calcium. In contrast to what was previously believed, neuron replacement in the vomeronasal epithelium appears to occur through a process of vertical migration in most mammals. New anatomical studies of the central pathways of the olfactory and vomeronasal systems indicated that these two systems converge on neurons in the telencephalon, providing an anatomical substrate for functional interactions. Combined anatomical, physiological and behavioral studies in mice provided new information that furthered our understanding of one of the most striking pheromonal phenomena, the Bruce effect. Finally, contrary to prior observations, new anatomical studies indicated that a vomeronasal organ (VNO) was present in human adults and reports were published indicating that this system might be functional. These latter observations are still controversial and require confirmation from independent laboratories.</AbstractText"
]
] |
[
[
"22850833",
"Complex biomedical systems: from basic science to translation.",
"The Department of Biomedical Engineering (BME) of the University of Southern California (BME@USC) has a longstanding tradition of advancing biomedicine through the development and application of novel engineering ideas. More than 80 primary and affiliated faculty members conduct cutting-edge research in a wide variety of areas, such as neuroengineering, biosystems and biosignal analysis, medical devices (including biomicroelectromechanical systems (bioMEMS) and bionanotechnology), biomechanics, bioimaging, and imaging informatics. Currently, the department hosts six internationally recognized research centers: the Biomimetic MicroElectronic Systems Engineering Research Center (funded by the National Science Foundation), the Biomedical Simulations Resource [funded by the National Institutes of Health (NIH)], the Medical Ultrasonic Transducer Center (funded by NIH), the Center for Neural Engineering, the Center for Vision Science and Technology (funded by an NIH Bioengineering Research Partnership Grant), and the Center for Genomic and Phenomic Studies in Autism (funded by NIH). BME@USC ranks in the top tier of all U.S. BME departments in terms of research funding per faculty.</AbstractText"
]
] |
23176028
|
Iranians' contribution to world literature on neuroscience.
|
The purpose of this study is to analyse Iranian scientific publications in the neuroscience subfields by librarians and neuroscientists, using Science Citation Index Expanded (SCIE) via Web of Science data over the period, 2002-2008.</AbstractText Data were retrieved from the SCIE. Data were collected from the 'subject area' of the database and classified by neuroscience experts into 14 subfields. To identify the citation patterns, we applied the 'impact factor' and the 'number of publication'. Data were also analysed using HISTCITE, Excel 2007 and SPSS.</AbstractText Seven hundred and thirty-four papers have been published by Iranian between 2002 and 2008. Findings showed a growing trend of neuroscience papers in the last 3 years with most papers (264) classified in the neuropharmacology subfield. There were fewer papers in neurohistory, psychopharmacology and artificial intelligence. International contributions of authors were mostly in the neurology subfield, and 'Collaboration Coefficient' for the neuroscience subfields in Iran was 0.686 which is acceptable. Most international collaboration between Iranians and developed countries was from USA. Eighty-seven percent of the published papers were in journals with the impact factor between 0 and 4; 25% of papers were published by the researchers affiliated to Tehran University of Medical Sciences.</AbstractText Progress of neuroscience in Iran is mostly seen in the neuropharmacology and the neurology subfields. Other subfields should also be considered as a research priority by health policymakers. As this study was carried out by the collaboration of librarians and neuroscientists, it has been proved valuable for both librarians and policymakers. This study may be encouraging for librarians from other developing countries.</AbstractText
|
[
[
"21312401",
"Functional brain imaging in schizophrenia: selected results and methods.",
"Functional brain imaging studies of patients with schizophrenia may be grouped into those that assume that the signs and symptoms of schizophrenia are due to disordered circuitry within a critical brain region and studies that assume that the signs and symptoms are due to disordered connections among brain regions. Studies have investigated the disordered functional brain anatomy of both the positive and negative symptoms of schizophrenia. Studies of spontaneous hallucinations find that although hallucinations are associated with abnormal brain activity in primary and secondary sensory areas, disordered brain activation associated with hallucinations is not limited to sensory systems. Disordered activation in non-sensory regions appear to contribute to the emotional strength and valence of hallucinations, to be a factor underlying an inability to distinguish ongoing mental processing from memories, and to reflect the brain's attempt to modulate the intensity of hallucinations and resolve conflicts with other processing demands. Brain activation studies support the view that auditory/verbal hallucinations are associated with an impaired ability of internal speech plans to modulate neural activation in sensory language areas. In early studies, negative symptoms of schizophrenia were hypothesized to be associated with impaired function in frontal brain areas. In support of this hypothesis meta-analytical studies have found that resting blood flow or metabolism in frontal cortex is reduced in schizophrenia, though the magnitude of the effect is only small to moderate. Brain activation studies of working memory (WM) functioning are typically associated with large effect sizes in the frontal cortex, whereas studies of functions other than WM generally reveal smaller effects. Findings from some functional connectivity studies have supported the hypothesis that schizophrenia patients experience impaired functional connections between frontal and temporal cortex, although the nature of the disordered connectivity is complex. More recent studies have used functional brain imaging to study neural compensation in schizophrenia, to serve as endophenotypes in genetic studies and to provide biomarkers in drug development studies. These emerging trends in functional brain imaging research are likely to help stimulate the development of a general neurobiological theory of the complex symptoms of schizophrenia.</AbstractText"
]
] |
[
[
"22963524",
"Non-genomic action of beclomethasone dipropionate on bronchoconstriction caused by leukotriene C4 in precision cut lung slices in the horse.",
"Glucocorticoids have been proven to be effective in the therapy of recurrent airway obstruction (RAO) in horses via systemic as well as local (inhalative) administration. Elective analysis of the effects of this drug on bronchoconstriction in viable lung tissue offers an insight into the mechanism of action of the inflammatory cascade occurring during RAO which is still unclear. The mechanism of action of steroids in treatment of RAO is thought to be induced through classical genomic pathways. We aimed at electively studying the effects of the glucocorticoid beclomethasone dipropionate on equine precision-cut lung slices (PCLS).PCLS were used to analyze ex-vivo effects of beclomethasone on inhibiting bronchoconstriction in the horse. The inhibiting effect was measured through instillation of a known mediator of inflammation and bronchoconstriction, leukotriene C4. For this, the accessory lobes of 13 horses subjected to euthanasia for reasons unrelated to the respiratory apparatus were used to obtain viable lung slices.</AbstractText After 30 minutes of PCLS incubation, beclomethasone showed to significantly inhibit the contraction of the bronchioles after instillation with leukotriene C4. The EC50 values of the two contraction curves (LTC4 with and without BDP) differed significantly from each other (p = 0.002). The possibility of a non-genomic rapid mechanism of action seems likely since transcriptional activities require a longer lag period.</AbstractText In human neuroendocrinology, high levels of glucocorticoids have been proven to function via a non-genomic mechanism of membrane receptors. The concentration of beclomethasone used on the lung slices in our study can be considered as high. This allows speculation about similar rapid non-genomic mechanisms of high-dosage inhaled glucocorticoids in the lower airways of horses. However, further assessment on a molecular basis is needed to confirm this.</AbstractText"
]
] |
23174433
|
When do people cooperate? The neuroeconomics of prosocial decision making.
|
Understanding the roots of prosocial behavior is an interdisciplinary research endeavor that has generated an abundance of empirical data across many disciplines. This review integrates research findings from different fields into a novel theoretical framework that can account for when prosocial behavior is likely to occur. Specifically, we propose that the motivation to cooperate (or not), generated by the reward system in the brain (extending from the striatum to the ventromedial prefrontal cortex), is modulated by two neural networks: a cognitive control system (centered on the lateral prefrontal cortex) that processes extrinsic cooperative incentives, and/or a social cognition system (including the temporo-parietal junction, the medial prefrontal cortex and the amygdala) that processes trust and/or threat signals. The independent modulatory influence of incentives and trust on the decision to cooperate is substantiated by a growing body of neuroimaging data and reconciles the apparent paradox between economic versus social rationality in the literature, suggesting that we are in fact wired for both. Furthermore, the theoretical framework can account for substantial behavioral heterogeneity in prosocial behavior. Based on the existing data, we postulate that self-regarding individuals (who are more likely to adopt an economically rational strategy) are more responsive to extrinsic cooperative incentives and therefore rely relatively more on cognitive control to make (un)cooperative decisions, whereas other-regarding individuals (who are more likely to adopt a socially rational strategy) are more sensitive to trust signals to avoid betrayal and recruit relatively more brain activity in the social cognition system. Several additional hypotheses with respect to the neural roots of social preferences are derived from the model and suggested for future research.</AbstractText
|
[
[
"12716950",
"Hierarchical processing in spoken language comprehension.",
"Understanding spoken language requires a complex series of processing stages to translate speech sounds into meaning. In this study, we use functional magnetic resonance imaging to explore the brain regions that are involved in spoken language comprehension, fractionating this system into sound-based and more abstract higher-level processes. We distorted English sentences in three acoustically different ways, applying each distortion to varying degrees to produce a range of intelligibility (quantified as the number of words that could be reported) and collected whole-brain echo-planar imaging data from 12 listeners using sparse imaging. The blood oxygenation level-dependent signal correlated with intelligibility along the superior and middle temporal gyri in the left hemisphere and in a less-extensive homologous area on the right, the left inferior frontal gyrus (LIFG), and the left hippocampus. Regions surrounding auditory cortex, bilaterally, were sensitive to intelligibility but also showed a differential response to the three forms of distortion, consistent with sound-form-based processes. More distant intelligibility-sensitive regions within the superior and middle temporal gyri, hippocampus, and LIFG were insensitive to the acoustic form of sentences, suggesting more abstract nonacoustic processes. The hierarchical organization suggested by these results is consistent with cognitive models and auditory processing in nonhuman primates. Areas that were particularly active for distorted speech conditions and, thus, might be involved in compensating for distortion, were found exclusively in the left hemisphere and partially overlapped with areas sensitive to intelligibility, perhaps reflecting attentional modulation of auditory and linguistic processes.</AbstractText"
]
] |
[
[
"23001148",
"An observational study of the effectiveness and safety of growth hormone (Humatrope(®)) treatment in Japanese children with growth hormone deficiency or Turner syndrome.",
"This study assessed the effectiveness and safety of growth hormone (GH; Humatrope(®)) therapy in Japanese children with GH deficiency (GHD) or Turner syndrome (TS) enrolled in the Genetics and Neuroendocrinology of Short Stature International Study (GeNeSIS). GeNeSIS is an open-label, multinational, multicenter, observational study conducted in 30 countries. In this interim report, there were 1129 GH treatment-naïve children with GHD, with a mean chronological age (± standard deviation) of 8.75 (3.32) years, and 90 girls with TS, with a mean chronological age of 8.93 (3.67) years. The mean height standard deviation score (SDS) increased from -2.73 (0.63) SD and -2.71 (0.63) SD at study entry to -2.22 (0.68) SD and -2.20 (0.60) SD after 1 year of treatment in the GHD and TS groups, respectively. In both groups, mean height SDS increased further with each year of treatment to 4 years; however, the magnitude of change in height SDS declined with time. The mean insulin-like growth factor-I SDS increased from below the mean of the reference population at study entry to a level similar to (GHD group) or higher than (TS group) the mean of the reference population during the 4-year treatment period. The incidence of serious adverse events (AEs), treatment-related AEs, and AEs related to glucose intolerance was low in both groups (0.1% to 3.0%). In conclusion, GH treatment in Japanese children with GHD or TS resulted in increased growth over a 4-year treatment period with a favorable safety profile; however, the improvements in growth declined with time.</AbstractText"
]
] |
22240730
|
Birdsong neurolinguistics: songbird context-free grammar claim is premature.
|
There are remarkable behavioral, neural, and genetic similarities between song learning in songbirds and speech acquisition in human infants. Previously, we have argued that this parallel cannot be extended to the level of sentence syntax. Although birdsong can indeed have a complex structure, it lacks the combinatorial complexity of human language syntax. Recently, this conclusion has been challenged by a report purporting to show that songbirds can learn so-called context-free syntactic rules and then use them to discriminate particular syllable patterns. Here, we demonstrate that the design of this study is inadequate to draw such a conclusion, and offer alternative explanations for the experimental results that do not require the acquisition and use of context-free grammar rules or a grammar of any kind, only the simpler hypothesis of acoustic similarity matching. We conclude that the evolution of vocal learning involves both neural homologies and behavioral convergence, and that human language reflects a unique cognitive capacity.</AbstractText
|
[
[
"19400719",
"The science of neural interface systems.",
"The ultimate goal of neural interface research is to create links between the nervous system and the outside world either by stimulating or by recording from neural tissue to treat or assist people with sensory, motor, or other disabilities of neural function. Although electrical stimulation systems have already reached widespread clinical application, neural interfaces that record neural signals to decipher movement intentions are only now beginning to develop into clinically viable systems to help paralyzed people. We begin by reviewing state-of-the-art research and early-stage clinical recording systems and focus on systems that record single-unit action potentials. We then address the potential for neural interface research to enhance basic scientific understanding of brain function by offering unique insights in neural coding and representation, plasticity, brain-behavior relations, and the neurobiology of disease. Finally, we discuss technical and scientific challenges faced by these systems before they are widely adopted by severely motor-disabled patients.</AbstractText"
]
] |
[
[
"23351052",
"On the neural basis of rule-guided behavior.",
"Human behavior emerges from a complex dynamic interaction between graded and context-sensitive neural processes, the biomechanics of our bodies, and the vicissitudes of our environments. These coupled processes bear little resemblance to the iterated application of simple symbolic rules. Still, there are circumstances under which our behavior appears to be guided by explicit mental rules. A prototypical case is when succinct verbal instructions are communicated and are promptly followed by another. How does the brain support such rule-guided behavior? How are explicit rules represented in the brain? How are rule representations shaped by experience? What neural processes form the foundation of our ability to systematically represent and apply rules from the vast range of possible rules? This article reviews a line of research that has sought a computational cognitive neuroscience account of rule-guided behavior in terms of the functioning of the prefrontal cortex, the basal ganglia, and related brain systems.</AbstractText"
]
] |
21645998
|
Are we studying and treating schizophrenia correctly?
|
New findings are rapidly revealing an increasingly detailed image of neural- and molecular-level dysfunction in schizophrenia, distributed throughout interconnected cortico-striato-pallido-thalamic circuitry. Some disturbances appear to reflect failures of early brain maturation, that become codified into dysfunctional circuit properties, resulting in a substantial loss of, or failure to develop, both cells and/or appropriate connectivity across widely dispersed brain regions. These circuit disturbances are variable across individuals with schizophrenia, perhaps reflecting the interaction of multiple different risk genes and epigenetic events. Given these complex and variable hard-wired circuit disturbances, it is worth considering how new and emerging findings can be integrated into actionable treatment models. This paper suggests that future efforts towards developing more effective therapeutic approaches for the schizophrenias should diverge from prevailing models in genetics and molecular neuroscience, and focus instead on a more practical three-part treatment strategy: 1) systematic rehabilitative psychotherapies designed to engage healthy neural systems to compensate for and replace dysfunctional higher circuit elements, used in concert with 2) medications that specifically target cognitive mechanisms engaged by these rehabilitative psychotherapies, and 3) antipsychotic medications that target nodal or convergent circuit points within the limbic-motor interface, to constrain the scope and severity of psychotic exacerbations and thereby facilitate engagement in cognitive rehabilitation. The use of targeted cognitive rehabilitative psychotherapy plus synergistic medication has both common sense and time-tested efficacy with numerous other neuropsychiatric disorders.</AbstractText
|
[
[
"15996748",
"Correlates of trait impulsiveness in performance measures and neuropsychological tests.",
"Performance measures of impulsiveness offer great promise for assessing this trait in clinical and experimental studies. However, little is known about their relative superiority or inferiority to standard cognitive performance measures as correlates of this trait. In this study, 58 healthy volunteers completed a self-rating of impulsiveness (Barratt Impulsiveness Scale) and a battery of neuropsychological tests. The test battery included measures of reaction time, attention, memory, fluency, and executive function, as well as two performance measures of impulsiveness--Time Estimation and a Go-No Go task. Self-ratings correlated moderately with a number of these test scores, but many correlations became non-significant after adjustment for age and education. Correlations with the Go-No Go task, verbal fluency, executive function measures (Trails B), and tasks requiring decision-making against time (Choice Reaction Time, Reaction Time to Paired Words and Paired Faces Memory Tasks, and response bias on the Continuous Performance Test) remained significant. Performance on the Go-No Go task was the strongest correlate of self-rated impulsiveness. The findings suggest that once general demographic or ability factors are accounted for, specialized performance tasks requiring decision-making and response organization under time pressure provide the most effective means of assessing this behavioral trait.</AbstractText"
]
] |
[
[
"21625624",
"\"Studying injured minds\" - the Vietnam head injury study and 40 years of brain injury research.",
"The study of those who have sustained traumatic brain injuries (TBI) during military conflicts has greatly facilitated research in the fields of neuropsychology, neurosurgery, psychiatry, neurology, and neuroimaging. The Vietnam Head Injury Study (VHIS) is a prospective, long-term follow-up study of a cohort of 1,221 Vietnam veterans with mostly penetrating brain injuries, which has stretched over more than 40 years. The scope of this study, both in terms of the types of injury and fields of examination, has been extremely broad. It has been instrumental in extending the field of TBI research and in exposing pressing medical and social issues that affect those who suffer such injuries. This review summarizes the history of conflict-related TBI research and the VHIS to date, as well as the vast range of important findings the VHIS has established.</AbstractText"
]
] |
23062307
|
Childhood adversity and DNA methylation of genes involved in the hypothalamus-pituitary-adrenal axis and immune system: whole-genome and candidate-gene associations.
|
In recent years, translational research involving humans and animals has uncovered biological and physiological pathways that explain associations between early adverse circumstances and long-term mental and physical health outcomes. In this article, we summarize the human and animal literature demonstrating that epigenetic alterations in key biological systems, the hypothalamus-pituitary-adrenal axis and immune system, may underlie such disparities. We review evidence suggesting that changes in DNA methylation profiles of the genome may be responsible for the alterations in hypothalamus-pituitary-adrenal axis and immune system trajectories. Using some preliminary data, we demonstrate how explorations of genome-wide and candidate-gene DNA methylation profiles may inform hypotheses and guide future research efforts in these areas. We conclude our article by discussing the many important future directions, merging perspectives from developmental psychology, molecular genetics, neuroendocrinology, and immunology, that are essential for furthering our understanding of how early adverse circumstances may shape developmental trajectories, particularly in the areas of stress reactivity and physical or mental health.</AbstractText
|
[
[
"15831717",
"Resting microglial cells are highly dynamic surveillants of brain parenchyma in vivo.",
"Microglial cells represent the immune system of the mammalian brain and therefore are critically involved in various injuries and diseases. Little is known about their role in the healthy brain and their immediate reaction to brain damage. By using in vivo two-photon imaging in neocortex, we found that microglial cells are highly active in their presumed resting state, continually surveying their microenvironment with extremely motile processes and protrusions. Furthermore, blood-brain barrier disruption provoked immediate and focal activation of microglia, switching their behavior from patroling to shielding of the injured site. Microglia thus are busy and vigilant housekeepers in the adult brain.</AbstractText"
]
] |
[
[
"23576843",
"Possibilities offered by implantable miniaturized cuff-electrodes for insect neurophysiology.",
"Recent advances in microsystems technology led to a miniaturization of cuff-electrodes, which suggests these electrodes not just for long-term neuronal recordings in mammalians, but also in medium-sized insects. In this study we investigated the possibilities offered by cuff-electrodes for neuroethology using insects as a model organism. The implantation in the neck of a tropical bushcricket resulted in high quality extracellular nerve recordings of different units responding to various acoustic, vibratory, optical and mechanical stimuli. In addition, multi-unit nerve activity related to leg movements was recorded in insects walking on a trackball. A drawback of bi-polar nerve recordings obtained during tethered flight was overlay of nerve activity with large amplitude muscle potentials. Interestingly, cuff-electrode recordings were robust to withstand walking and flight activity so that good quality nerve recordings were possible even three days after electrode implantation. Recording multi-unit nerve activity in intact insects required an elaborate spike sorting algorithm in order to discriminate neuronal units responding to external stimuli from background activity. In future, a combination of miniaturized cuff-electrodes and light-weight amplifiers equipped with a wireless transmitter will allow the investigation of neuronal processes underlying natural behavior in freely moving insects. By this means cuff-electrodes may contribute to the development of realistic neuronal models simulating neuronal processes underlying natural insect behavior, such like mate choice and predator avoidance.</AbstractText"
]
] |
23196557
|
[A new neuroscientific approach using decoded neurofeedback (DecNef)].
|
Neurofeedback is defined as a method to read out information from the brain and feed the information back to the brain. This technology has developed in the past ten years and attracted considerable attention as potential treatments for rehabilitation and psychiatric disease. We recently invented the decoded neurofeedback (DecNef) method, a new neurofeedback technique using functional magnetic resonance imaging. With DecNef, subjects were trained to regulate their brain activation pattern in a specific area and lead the pattern to a target state. We found that the DecNef training for several days leads to perceptual improvement that corresponds to the induced target state. DecNef enables us to test cause-and-effect relationships between neural activation in a target brain area and changes in perception, cognition, and behavior. In this sense, this method can be a powerful tool in cognitive and systems neuroscience. In addition, the concept of DecNef, leading a neural activation pattern to a specific state, can be applied for a variety of fields including engineering and medical treatment.</AbstractText
|
[
[
"15831717",
"Resting microglial cells are highly dynamic surveillants of brain parenchyma in vivo.",
"Microglial cells represent the immune system of the mammalian brain and therefore are critically involved in various injuries and diseases. Little is known about their role in the healthy brain and their immediate reaction to brain damage. By using in vivo two-photon imaging in neocortex, we found that microglial cells are highly active in their presumed resting state, continually surveying their microenvironment with extremely motile processes and protrusions. Furthermore, blood-brain barrier disruption provoked immediate and focal activation of microglia, switching their behavior from patroling to shielding of the injured site. Microglia thus are busy and vigilant housekeepers in the adult brain.</AbstractText"
]
] |
[
[
"23176028",
"Iranians' contribution to world literature on neuroscience.",
"The purpose of this study is to analyse Iranian scientific publications in the neuroscience subfields by librarians and neuroscientists, using Science Citation Index Expanded (SCIE) via Web of Science data over the period, 2002-2008.</AbstractText Data were retrieved from the SCIE. Data were collected from the 'subject area' of the database and classified by neuroscience experts into 14 subfields. To identify the citation patterns, we applied the 'impact factor' and the 'number of publication'. Data were also analysed using HISTCITE, Excel 2007 and SPSS.</AbstractText Seven hundred and thirty-four papers have been published by Iranian between 2002 and 2008. Findings showed a growing trend of neuroscience papers in the last 3 years with most papers (264) classified in the neuropharmacology subfield. There were fewer papers in neurohistory, psychopharmacology and artificial intelligence. International contributions of authors were mostly in the neurology subfield, and 'Collaboration Coefficient' for the neuroscience subfields in Iran was 0.686 which is acceptable. Most international collaboration between Iranians and developed countries was from USA. Eighty-seven percent of the published papers were in journals with the impact factor between 0 and 4; 25% of papers were published by the researchers affiliated to Tehran University of Medical Sciences.</AbstractText Progress of neuroscience in Iran is mostly seen in the neuropharmacology and the neurology subfields. Other subfields should also be considered as a research priority by health policymakers. As this study was carried out by the collaboration of librarians and neuroscientists, it has been proved valuable for both librarians and policymakers. This study may be encouraging for librarians from other developing countries.</AbstractText"
]
] |
23428294
|
Neuropsychological assessment and the paradox of ADHD.
|
Attention-deficit hyperactivity disorder (ADHD) is a behaviorally defined diagnosis. Despite the fact that neuropsychological tests have typically been used successfully to investigate the functional neuroanatomy of ADHD in neuroimaging research paradigms, these tests have been of surprisingly limited utility in the clinical diagnosis of the disorder. This article examines this paradox by reviewing the characteristics of the Diagnostic and Statistical Manual of Mental Disorders diagnosis versus neuropsychological nomenclature, by reviewing the assumptions about etiologies for ADHD and by demonstrating how an emerging dimensional approach to diagnostic assessment can be combined with large-scale brain network studies to enhance the role of neuropsychological evaluation within clinical settings. This selective topical review is intended to arm practicing neuropsychologists with knowledge of new ideas, theories, and methods related to the causes of ADHD to prepare them for meaningful advances in understanding and assessing the disorder that are possible during the next decade.</AbstractText
|
[
[
"21325522",
"Origin and determination of inhibitory cell lineages in the vertebrate retina.",
"Multipotent progenitors in the vertebrate retina often generate clonally related mixtures of excitatory and inhibitory neurons. The postmitotically expressed transcription factor, Ptf1a, is essential for all inhibitory fates in the zebrafish retina, including three types of horizontal and 28 types of amacrine cell. Here, we show that specific types of inhibitory neurons arise from the cell-autonomous influence of Ptf1a in the daughters of fate-restricted progenitors, such as Ath5 or Vsx1/2-expressing progenitors, and that in the absence of Ptf1a, cells that would have become these specific inhibitory subtypes revert to the histogenetically appropriate excitatory subtypes of the same lineage. Altered proportions of amacrine subtypes respecified by the misexpression of Ptf1a in the Ath5 lineage suggest that Ath5-expressing progenitors are biased, favoring the generation of some subtypes more than others. Yet the full array of inhibitory cell subtypes in Ath5 mutants implies the existence of Ath5-independent factors involved in inhibitory cell specification. We also show that an extrinsic negative feedback on the expression of Ptf1a provides a control mechanism by which the number of any and all types of inhibitory cells in the retina can be regulated in this lineage-dependent way.</AbstractText"
]
] |
[
[
"23275858",
"Brain state-triggered stimulus delivery: An efficient tool for probing ongoing brain activity.",
"What is the relationship between variability in ongoing brain activity <i"
]
] |
22520647
|
European study of research and development in mobility technology for persons with disabilities.
|
\In the fall of 2010, the National Science Foundation, the National Institutes of Health and the U.S. Veteran's Administration jointly supported a review of mobility technology in Europe. A delegation of American Scientists traveled to Europe to visit a number of research centers and engaged in a demonstration and dialogue related to the global state-of-the-art for mobility impairment rectification and augmentation. From the observations and exchanges between the U.S. delegation and host institutions, the researchers were able to derive a series of papers which are now published in this thematic series of Journal of NeuroEngineering and Rehabilitation. The papers describe the main themes of the European mobility technology research activities showing a healthy picture of research and innovation in the field.</AbstractText
|
[
[
"20427643",
"Emotional automaticity is a matter of timing.",
"There has been a long controversy concerning whether the amygdala's response to emotional stimuli is automatic or dependent on attentional load. Using magnoencephalography and an advanced beamformer source localization technique, we found that amygdala automaticity was a function of time: while early amygdala responding to emotional stimuli (40-140 ms) was unaffected by attentional load, later amygdala response (280-410 ms), subsequent to frontoparietal cortex activity, was modulated by attentional load.</AbstractText"
]
] |
[
[
"22155385",
"Metabotropic glutamate receptor 1 (mGluR1): antibody specificity and receptor expression in cultured primary neurons.",
"The availability of high quality, well-characterized antibodies for molecular and cellular neuroscience studies is important. However, not all available antibodies are rigorously evaluated, nor are limitations of particular antibodies often reported. We have examined a panel of currently available mGluR1 antibodies and have identified which ones are selective for use by western blots and immunocytochemistry. We have also specifically determined whether the antibodies cross-react to recognize mGluR5, by examining (1) tissue from both mGluR1 and mGluR5 knock-out mice and (2) primary cortical cultures, in which mGluR5 is widely expressed but mGluR1 is not. Together, these data provide a baseline characterization of antibodies that can and cannot be reliably used in these types of studies, and will hopefully facilitate and positively impact the research efforts of others studying mGluR1.</AbstractText"
]
] |
22751865
|
Human aquaporin 4281-300 is the immunodominant linear determinant in the context of HLA-DRB1*03:01: relevance for diagnosing and monitoring patients with neuromyelitis optica.
|
OBJECTIVE To identify linear determinants of human aquaporin 4 (hAQP4) in the context of HLA-DRB1*03:01. DESIGN In this controlled study with humanized experimental animals, HLA-DRB1*03:01 transgenic mice were immunized with whole-protein hAQP4 emulsified in complete Freund adjuvant. To test T-cell responses, lymph node cells and splenocytes were cultured in vitro with synthetic peptides 20 amino acids long that overlap by 10 amino acids across the entirety of hAQP4. The frequency of interferon γ, interleukin (IL) 17, granulocyte-macrophage colony-stimulating factor, and IL-5-secreting CD4+ T cells was determined by the enzyme-linked immunosorbent sport assay. Quantitative immunofluorescence microscopy was performed to determine whether hAQP4281-300 inhibits the binding of anti-hAQP4 recombinant antibody to surface full-length hAQP4. SETTING Academic neuroimmunology laboratories. SUBJECTS Humanized HLA-DRB1*03:01+/+ H-2b-/- transgenic mice on a B10 background. RESULTS Peptide hAQP4281-300 generated a significantly (P &lt;.01) greater TH1 and TH17 immune response than any of the other linear peptides screened. This 20mer peptide contains 2 dominant immunogenic 15mer peptides. hAQP4284-298 induced predominantly an IL-17 and granulocyte-macrophage colony-stimulating factor TH cell phenotype, whereas hAQP4285-299 resulted in a higher frequency of TH1 cells. hAQP4281-300 did not interfere with recombinant AQP4 autoantibody binding. CONCLUSIONS hAQP4281-330 is the dominant linear immunogenic determinant of hAQP4 in the context of HLA-DRB1*03:01. Within hAQP4281-330 are 2 dominant immunogenic determinants that induce differential TH phenotypes. hAQP4 determinants identified in this study can serve as diagnostic biomarkers in patients with neuromyelitis optica and may facilitate the monitoring of treatment responses to pharmacotherapies.</AbstractText
|
[
[
"21731699",
"Recognition of 5-hydroxymethylcytosine by the Uhrf1 SRA domain.",
"Recent discovery of 5-hydroxymethylcytosine (5hmC) in genomic DNA raises the question how this sixth base is recognized by cellular proteins. In contrast to the methyl-CpG binding domain (MBD) of MeCP2, we found that the SRA domain of Uhrf1, an essential factor in DNA maintenance methylation, binds 5hmC and 5-methylcytosine containing substrates with similar affinity. Based on the co-crystal structure, we performed molecular dynamics simulations of the SRA:DNA complex with the flipped cytosine base carrying either of these epigenetic modifications. Our data indicate that the SRA binding pocket can accommodate 5hmC and stabilizes the flipped base by hydrogen bond formation with the hydroxyl group.</AbstractText"
]
] |
[
[
"24294562",
"Dorello's Canal and Gruber's Ligament: Historical Perspective.",
"Wenzel Leopold Gruber and Primo Dorello were great anatomists and researchers during the 19th and 20th centuries. Their contributions to neuroanatomy-namely the Gruber's (petrosphenoidal) ligament and Dorello's canal, respectively-have come to be important structures in various approaches through the middle fossa. These structures have also helped provide us with an understanding of the mechanism of sixth nerve paresis in various pathological conditions, such as raised intracranial pressure and Gradenigo syndrome. Their numerous publications have stood as a reference to anatomical researchers. Gruber's description of internal mesogastric hernia and the Meckel-Gruber anastomosis are also widely known in medical literature. The following article is an attempt to reflect upon the life and works of Gruber and Dorello and the importance of their research.</AbstractText"
]
] |
23276394
|
Biological mechanisms associated with increased perseveration and hyperactivity in a genetic mouse model of neurodevelopmental disorder.
|
Chromosomal deletions at Xp22.3 appear to influence vulnerability to the neurodevelopmental disorders attention deficit hyperactivity disorder (ADHD) and autism. 39,X(Y*)O mice, which lack the murine orthologue of the Xp22.3 ADHD candidate gene STS (encoding steroid sulfatase), exhibit behavioural phenotypes relevant to such disorders (e.g. hyperactivity), elevated hippocampal serotonin (5-HT) levels, and reduced serum levels of dehydroepiandrosterone (DHEA). Here we initially show that 39,X(Y*)O mice are also deficient for the recently-characterised murine orthologue of the Xp22.3 autism candidate gene ASMT (encoding acetylserotonin-O-methyltransferase). Subsequently, to specify potential behavioural correlates of elevated hippocampal 5-HT arising due to the genetic lesion, we compared 39,X(Y*)O MF1 mice to 40,XY MF1 mice on behavioural tasks taxing hippocampal and/or 5-HT function (a 'foraging' task, an object-location task, and the 1-choice serial reaction time task of impulsivity). Although Sts/Asmt deficiency did not influence foraging behaviour, reactivity to familiar objects in novel locations, or 'ability to wait', it did result in markedly increased response rates; these rates correlated with hippocampal 5-HT levels and are likely to index behavioural perseveration, a frequent feature of neurodevelopmental disorders. Additionally, we show that whilst there was no systematic relationship between serum DHEA levels and hippocampal 5-HT levels across 39,X(Y*)O and 40,XY mice, there was a significant inverse linear correlation between serum DHEA levels and activity. Our data suggest that deficiency for genes within Xp22.3 could influence core behavioural features of neurodevelopmental disorders via dissociable effects on hippocampal neurochemistry and steroid hormone levels, and that the mediating neurobiological mechanisms may be investigated in the 39,X(Y*)O model.</AbstractText
|
[
[
"18457512",
"Timing, storage, and comparison of stimulus duration engage discrete anatomical components of a perceptual timing network.",
"The temporal discrimination paradigm requires subjects to compare the duration of a probe stimulus to that of a sample previously stored in working or long-term memory, thus providing an index of timing that is independent of a motor response. However, the estimation process itself comprises several component cognitive processes, including timing, storage, retrieval, and comparison of durations. Previous imaging studies have attempted to disentangle these components by simply measuring brain activity during early versus late scanning epochs. We aim to improve the temporal resolution and precision of this approach by using rapid event-related functional magnetic resonance imaging to time-lock the hemodynamic response to presentation of the sample and probe stimuli themselves. Compared to a control (color-estimation) task, which was matched in terms of difficulty, sustained attention, and motor preparation requirements, we found selective activation of the left putamen for the storage (\"encoding\") of stimulus duration into working memory (WM). Moreover, increased putamen activity was linked to enhanced timing performance, suggesting that the level of putamen activity may modulate the depth of temporal encoding. Retrieval and comparison of stimulus duration in WM selectively activated the right superior temporal gyrus. Finally, the supplementary motor area was equally active during both sample and probe stages of the task, suggesting a fundamental role in timing the duration of a stimulus that is currently unfolding in time.</AbstractText"
]
] |
[
[
"23269483",
"Metabolomic analysis of cerebrospinal fluid indicates iron deficiency compromises cerebral energy metabolism in the infant monkey.",
"Iron deficiency anemia affects many pregnant women and young infants worldwide. The health impact is significant, given iron's known role in many body functions, including oxidative and lipid metabolism, protein synthesis and brain neurochemistry. The following research determined if (1)H NMR spectroscopy-based metabolomic analysis of cerebrospinal fluid (CSF) could detect the adverse influence of early life iron deficiency on the central nervous system. Using a controlled dietary model in 43 infant primates, distinct differences were found in spectra acquired at 600 MHz from the CSF of anemic monkeys. Three metabolite ratios, citrate/pyruvate, citrate/lactate and pyruvate/glutamine ratios, differed significantly in the iron deficient infant and then normalized following the consumption of dietary iron and improvement of clinical indices of anemia in the heme compartment. This distinctive metabolomic profile associated with anemia in the young infant indicates that CSF can be employed to track the neurological effects of iron deficiency and benefits of iron supplementation.</AbstractText"
]
] |
23130007
|
When Do We Confuse Self and Other in Action Memory? Reduced False Memories of Self-Performance after Observing Actions by an Out-Group vs. In-Group Actor.
|
Observing another person performing an action can lead to a false memory of having performed the action oneself - the observation-inflation effect. In the experimental paradigm, participants first perform or do not perform simple actions, and then observe another person perform some of these actions. The observation-inflation effect is found when participants later remember performing actions that they have merely observed. In this case, self and other are confused in action memory. We examined social conditions of this self-other confusion when remembering actions, specifically whether the effect depends on the observed actor's group membership. In our experiment, we manipulated group membership based on physical appearance, specifically complexion of the hands. Fair-skinned participants observed either an in-group (i.e., fair-skinned) or an out-group (i.e., dark-skinned) actor. Our results revealed that the observed actor's group membership moderated the observation-inflation effect: False memories were significantly reduced when the actor was from the out-group (vs. in-group). We found no difference to a control condition in which the actor wore black gloves, suggesting that distinctiveness of perceptual or sensory features alone (due to the out-group member's dark skin) is not critical. We discuss these findings in light of social-neuroscience studies demonstrating the impact of an observed person's group membership on motor simulation. Overall, our findings suggest that action memory can be affected by a ubiquitous feature of people's social perception, that is, group-based social categorization of others.</AbstractText
|
[
[
"19298949",
"Perceptual simulation in conceptual combination: evidence from property generation.",
"In three experiments, participants received nouns or noun phrases for objects and verbally generated their properties (\"feature listing\"). Several sources of evidence indicated that participants constructed perceptual simulations to generate properties for the noun phrases during conceptual combination. First, the production of object properties for noun phrases depended on occlusion, with unoccluded properties being generated more often than occluded properties. Because a perceptual variable affected conceptual combination, perceptual simulations appeared central to combining the concepts for modifiers and head nouns. Second, neutral participants produced the same distributions of properties as participants instructed to describe images, suggesting that the conceptual representations used by neutral participants were similar to the mental images used by imagery participants. Furthermore, the property distributions for neutral and imagery participants differed from those for participants instructed to produce word associations. Third, participants produced large amounts of information about background situations associated with the object cues, suggesting that the simulations used to generate properties were situated. The experiments ruled out alternative explanations that simulation effects occur only for familiar noun phrases associated with perceptual memories and that rules associated with modifiers produce occlusion effects. A process model of the property generation task grounded in simulation mechanisms is presented. The possibility of integrating the simulation account of conceptual combination with traditional accounts and well-established findings is explored.</AbstractText"
]
] |
[
[
"23055968",
"Detection of self-paced reaching movement intention from EEG signals.",
"Future neuroprosthetic devices, in particular upper limb, will require decoding and executing not only the user's intended movement type, but also when the user intends to execute the movement. This work investigates the potential use of brain signals recorded non-invasively for detecting the time before a self-paced reaching movement is initiated which could contribute to the design of practical upper limb neuroprosthetics. In particular, we show the detection of self-paced reaching movement intention in single trials using the readiness potential, an electroencephalography (EEG) slow cortical potential (SCP) computed in a narrow frequency range (0.1-1 Hz). Our experiments with 12 human volunteers, two of them stroke subjects, yield high detection rates prior to the movement onset and low detection rates during the non-movement intention period. With the proposed approach, movement intention was detected around 500 ms before actual onset, which clearly matches previous literature on readiness potentials. Interestingly, the result obtained with one of the stroke subjects is coherent with those achieved in healthy subjects, with single-trial performance of up to 92% for the paretic arm. These results suggest that, apart from contributing to our understanding of voluntary motor control for designing more advanced neuroprostheses, our work could also have a direct impact on advancing robot-assisted neurorehabilitation.</AbstractText"
]
] |
23279177
|
Neurochemistry of schizophrenia: the contribution of neuroimaging postmortem pathology and neurochemistry in schizophrenia.
|
The advent of molecular neuroimaging has greatly impacted on understanding the neurochemical changes occurring in the CNS from subjects with psychiatric disorders, especially schizophrenia. This review focuses on the outcomes from studies using positron emission tomography and single photon emission computer tomography that have measure levels of neurotransmitter receptors and transporters in the CNS from subjects with schizophrenia. One outcome from such studies is the confirmation of a number of findings using postmortem tissue, but in the case of neuroimaging, using drug na�ve and drug free subjects. These findings add weight to the argument that findings from postmortem studies are not an artifact of tissue processing or a simple drug effect. However, there are some important unique findings from studies using neuroimaging studies. These include evidence to suggest that in schizophrenia there are alterations in dopamine synthesis and release, which are not accompanied by an appropriate down-regulation of dopamine D2 receptors. There are also data that would support the notion that decreased levels of serotonin 2A receptors may be an early marker of the onset of schizophrenia. Whilst there is a clear need for on-going development of neuroimaging ligands to expand the number of targets that can be studied and to increase cohort sizes in neuroimaging studies to give power to the analyses of the resulting data, current studies show that existing neuroimaging studies have already extended our understanding of the underlying pathophysiology of psychiatric disorders such as schizophrenia.</AbstractText
|
[
[
"11330208",
"Microdialysis perfusion of orexin-A in the basal forebrain increases wakefulness in freely behaving rats.",
"Recent work indicates that the orexin/hypocretin-containing neurons of the lateral hypothalamus are involved in control of REM sleep phenomena, but site-specific actions in control of wakefulness have been less studied. Orexin-containing neurons project to both brainstem and forebrain regions that are known to regulate sleep and wakefulness, including the field of cholinergic neurons in the basal forebrain (BF) that is implicated in regulation of wakefulness, and includes, in the rat, the horizontal limb of the diagonal band, the substantia innominata, and the magnocellular preoptic region. The present study used microdialysis perfusion of orexin-A directly in the cholinergic BF region of rat to test the hypothesis that orexin-A enhances W via a local action in the BF. A significant dose-dependent increase in W was produced by the perfusion of three doses of orexin-A in the BF (0.1, 1.0, and 10.0 microM), with 10.0 microM producing more than a 5-fold increase in wakefulness, which occupied 44% of the light (inactive) phase recording period. Orexin-A perfusion also produced a significant dose-dependent decrease in nonREM sleep, and a trend-level decrease in REM sleep. The results clearly demonstrate a potent capacity of orexin-A to induce wakefulness via a local action in the BF, and are consistent with previous work indicating that the BF cholinergic zone neurons have a critical role in the regulation of EEG activation and W. The data suggest further that orexin-A has a significant role in the regulation of arousal/wakefulness, in addition to the previously described role of orexin in the regulation and expression of REM sleep and REM sleep-related phenomena.</AbstractText"
]
] |
[
[
"22986407",
"How a common variant in the growth factor receptor gene, NTRK1, affects white matter.",
"Growth factors and their receptors are important for cellular migration as well as axonal guidance and myelination in the brain. They also play a key role in programmed cell death, and are implicated in a number of mental illnesses. Recently, we reported that healthy young adults who carry the T allele variant in the growth factor gene, NTRK1 (at location rs6336), had lower white matter integrity than non-carriers on diffusion images of the brain. Diffusion tensor imaging (DTI) revealed how this single nucleotide polymorphism affects white matter microstructure in human populations; DTI is also used to identify characteristic features of brain connectivity in typically developing children and in patients. Newly discovered links between neuroimaging measures and growth factors whose molecular neuroscience is well known offer an important step in understanding mechanisms that contribute to brain connectivity. Altered fiber connectivity may mediate the relationship between some genetic risk factors and a variety of mental illnesses.</AbstractText"
]
] |
23197532
|
A large-scale model of the functioning brain.
|
A central challenge for cognitive and systems neuroscience is to relate the incredibly complex behavior of animals to the equally complex activity of their brains. Recently described, large-scale neural models have not bridged this gap between neural activity and biological function. In this work, we present a 2.5-million-neuron model of the brain (called "Spaun") that bridges this gap by exhibiting many different behaviors. The model is presented only with visual image sequences, and it draws all of its responses with a physically modeled arm. Although simplified, the model captures many aspects of neuroanatomy, neurophysiology, and psychological behavior, which we demonstrate via eight diverse tasks.</AbstractText
|
[
[
"8854339",
"Role of an S4-S5 linker in sodium channel inactivation probed by mutagenesis and a peptide blocker.",
"A pair of conserved methionine residues, located on the cytoplasmic linker between segments S4 and S5 in the fourth domain of human heart Na channels (hH1), plays a role in the kinetics and voltage dependence of inactivation. Substitution of these residues by either glutamine (M1651M1652/QQ) or alanine (MM/AA) increases the inactivation time constant (tau) at depolarized voltages, shifts steady-state inactivation (h infinity) in a depolarized direction, and decreases the time constant for recovery from inactivation. The data indicate that the mutations affect the rate constants for both binding and unbinding of a hypothetical inactivation particle from its binding site. Cytoplasmic application of the pentapeptide KIFMK in Na channels mutated to remove inactivation produces current decays resembling inactivation (Eaholtz, G., T. Scheuer, and W.A. Catterall. 1994. Neuron. 12: 1041-1048.). KIFMK produces a concentration-dependent, voltage-independent increase in the decay rate of MM/QQ and MM/AA currents at positive membrane potentials (Ki approximately 30 microM), while producing only a small increase in the decay rate of wild-type currents at a concentration of 200 microM. Although MM/QQ inactivates approximately 2.5-fold faster than MM/AA in the absence of peptide, the estimated rate constants for peptide block and unblock do not differ in these mutants. External Na+ ions antagonize the block by cytoplasmic KIFMK of MM/AA channels, but not the inactivation kinetics of this mutant in the absence of peptide. The effect of external [Na+] is interpreted as a voltage-dependent knock-off mechanism. The data provide evidence that KIFMK can only block channels when they are open and that peptide block does not mimic the inactivation process.</AbstractText"
]
] |
[
[
"23505339",
"Baby Steps to Superintelligence: Neuroprosthetics and Children.",
"Children surviving neural injuries face challenges not seen by their adult counterparts, namely that they experience neural injury before reaching neurodevelopmental maturity. Neural prostheses offer one possible path to recovery, along with the potential for functional outcomes that could exceed expectations. Although the first cochlear implant was placed more than fifty years ago, the field of neuroprosthetics is still relatively young. Several types of neural prostheses are in development stages ranging from animal models to (adult) human trials. In this paper, I discuss how neural prostheses may assist recovery for children surviving neural injury. I argue that approaching the use of neural prosthetics in children with considerations derived from transhumanism alongside traditional bioethics can provide an opportunity to reframe adult-focused ethics toward a child/family focus and to strip away the prejudicial metaphor of cyborgization.</AbstractText"
]
] |
22143364
|
Postural tachycardia syndrome--current experience and concepts.
|
Postural tachycardia syndrome (PoTS) is a poorly understood but important cause of orthostatic intolerance resulting from cardiovascular autonomic dysfunction. PoTS is distinct from the syndromes of autonomic failure usually associated with orthostatic hypotension, such as pure autonomic failure and multiple system atrophy. Individuals affected by PoTS are mainly young (aged between 15 years and 40 years) and predominantly female. The symptoms--palpitations, dizziness and occasionally syncope--mainly occur when the patient is standing upright, and are often relieved by sitting or lying flat. Common stimuli in daily life, such as modest exertion, food ingestion and heat, are now recognized to be capable of exacerbating the symptoms. Onset of the syndrome can be linked to infection, trauma, surgery or stress. PoTS can be associated with various other disorders; in particular, joint hypermobility syndrome (also known as Ehlers-Danlos syndrome hypermobility type, formerly termed Ehlers-Danlos syndrome type III). This Review describes the characteristics and neuroepidemiology of PoTS, and outlines possible pathophysiological mechanisms of this syndrome, as well as current and investigational treatments.</AbstractText
|
[
[
"21749952",
"Social neuroscience: mirror neurons recorded in humans.",
"New single-cell recordings show that humans do have mirror neurons, and in more brain regions than previously suspected. Some action-execution neurons were seen to be inhibited during observation, possibly preventing imitation and helping self/other discrimination.</AbstractText"
]
] |
[
[
"21960308",
"Open questions in computational motor control.",
"Computational motor control covers all applications of quantitative tools for the study of the biological movement control system. This paper provides a review of this field in the form of a list of open questions. After an introduction in which we define computational motor control, we describe: a Turing-like test for motor intelligence; internal models, inverse model, forward model, feedback error learning and distal teacher; time representation, and adaptation to delay; intermittence control strategies; equilibrium hypotheses and threshold control; the spatiotemporal hierarchy of wide sense adaptation, i.e., feedback, learning, adaptation, and evolution; optimization based models for trajectory formation and optimal feedback control; motor memory, the past and the future; and conclude with the virtue of redundancy. Each section in this paper starts with a review of the relevant literature and a few more specific studies addressing the open question, and ends with speculations about the possible answer and its implications to motor neuroscience. This review is aimed at concisely covering the topic from the author's perspective with emphasis on learning mechanisms and the various structures and limitations of internal models.</AbstractText"
]
] |
22481743
|
Brain enabled by next-generation neurotechnology: using multiscale and multimodal models.
|
As many articles in this issue of IEEE Pulse demonstrate, interfacing directly with the brain presents several fundamental challenges. These challenges reside at multiple levels and span many disciplines, ranging from the need to understand brain states at the level of neural circuits to creating technological innovations to facilitate new therapeutic options. The goal of our multiuniversity research team, composed of researchers from Stanford University, Brown University, the University of California at San Francisco (UCSF), and the University College London (UCL), is to substantially elevate the fundamental understanding of brain information processing and its relationship with sensation, behavior, and injury. Our team was assembled to provide expertise ranging from neuroscience to neuroengineering and to neurological and psychiatric clinical guidance, all of which are critical to the overarching research goal. By employing a suite of innovative experimental, computational, and theoretical approaches, the Defense Advanced Research Projects Agency (DARPA) Reorganization and Plasticity to Accelerate Injury Recovery (REPAIR) team has set its sights on learning how the brain and its microcircuitry react (e.g., to sudden physiological changes) and what can be done to encourage recovery from such (reversible) injury. In this article, we summarize some of the team's technical goals, approaches, and early illustrative results.</AbstractText
|
[
[
"15928068",
"Reward, motivation, and emotion systems associated with early-stage intense romantic love.",
"Early-stage romantic love can induce euphoria, is a cross-cultural phenomenon, and is possibly a developed form of a mammalian drive to pursue preferred mates. It has an important influence on social behaviors that have reproductive and genetic consequences. To determine which reward and motivation systems may be involved, we used functional magnetic resonance imaging and studied 10 women and 7 men who were intensely \"in love\" from 1 to 17 mo. Participants alternately viewed a photograph of their beloved and a photograph of a familiar individual, interspersed with a distraction-attention task. Group activation specific to the beloved under the two control conditions occurred in dopamine-rich areas associated with mammalian reward and motivation, namely the right ventral tegmental area and the right postero-dorsal body and medial caudate nucleus. Activation in the left ventral tegmental area was correlated with facial attractiveness scores. Activation in the right anteromedial caudate was correlated with questionnaire scores that quantified intensity of romantic passion. In the left insula-putamen-globus pallidus, activation correlated with trait affect intensity. The results suggest that romantic love uses subcortical reward and motivation systems to focus on a specific individual, that limbic cortical regions process individual emotion factors, and that there is localization heterogeneity for reward functions in the human brain.</AbstractText"
]
] |
[
[
"22963990",
"Further characterization of repetitive behavior in C58 mice: developmental trajectory and effects of environmental enrichment.",
"Aberrant repetitive behaviors are commonly observed in a variety of neurodevelopmental, neurological, and neuropsychiatric disorders. Little is known about the specific neurobiological mechanisms that underlie such behaviors, however, and effective treatments are lacking. Valid animal models can aid substantially in identifying pathophysiological factors mediating aberrant repetitive behavior and aid in treatment development. The C58 inbred mouse strain is a particularly promising model, and we have further characterized its repetitive behavior phenotype. Compared to C57BL/6 mice, C58 mice exhibit high rates of spontaneous hindlimb jumping and backward somersaulting reaching adult frequencies by 5 weeks post-weaning and adult temporal organization by 2 weeks post-weaning. The development of repetitive behavior in C58 mice was markedly attenuated by rearing these mice in larger, more complex environments. In addition to characterizing repetitive motor behavior, we also assessed related forms of inflexible behavior that reflect restricted and perseverative responding. Contrary to our hypothesis, C58 mice did not exhibit increased marble burying nor did they display reduced exploratory behavior in the holeboard task. The C58 strain appears to be a very useful model for the repetitive motor behavior characteristic of a number of clinical disorders. As an inbred mouse strain, studies using the C58 model can take full advantage of the tool kit of modern genetics and molecular neuroscience. This technical advantage makes the model a compelling choice for use in studies designed to elucidate the etiology and pathophysiology of aberrant repetitive behavior. Such findings should, in turn, translate into effective new treatments.</AbstractText"
]
] |
23493966
|
Exploring sensory neuroscience through experience and experiment.
|
Many phenomena that we take for granted are illusions - color and motion on a TV or computer monitor, for example, or the impression of space in a stereo music recording. Even the stable image that we perceive when looking directly at the real world is illusory. One of the important lessons from sensory neuroscience is that our perception of the world is constructed rather than received. Sensory illusions effectively capture student interest, but how do you then move on to substantive discussion of neuroscience? This article illustrates several illusions, attempts to connect them to neuroscience, and shows how students can explore and experiment with them. Even when (as is often the case) there is no agreed-upon mechanistic explanation for an illusion, students can form hypotheses and test them by manipulating stimuli and measuring their effects. In effect, students can experiment with illusions using themselves as subjects.</AbstractText
|
[
[
"11377409",
"Double-blind naltrexone and placebo comparison study in the treatment of pathological gambling.",
"The authors' goal was to assess the efficacy and tolerability of naltrexone in the treatment of pathologic gambling disorder.</AbstractText Eighty-three subjects who met criteria for DSM-IV pathologic gambling disorder were enrolled in a 1-week single-blind placebo lead-in followed by an 11-week double-blind naltrexone or placebo trial. Naltrexone was started at 25 mg/day and titrated upward until maximum symptom improvement or 250 mg/day was achieved. Gambling symptom change was assessed with the patient-rated Clinical Global Impression (PG-CGI-PT), clinician-rated CGI (PG-CGI-MD), and the Gambling Symptom Rating Scale (G-SAS). Side effects were monitored weekly and liver function tests biweekly.</AbstractText Data from 45 patients were analyzed. Using random regression analysis, significant improvement was noted in all three gambling symptom measures: patient-rated Clinical Global Impression, p <.001; clinician-rated CGI, p <.001; Gambling Symptom Rating Scale, p <.019. At study end, 75% of subjects taking naltrexone were much or very much improved on both the PE-CEI PT and the PG-CGI-MD, compared with only 24% of those on placebo. Elevated liver enzymes occurred in four subjects who were taking analgesics concurrently. Nausea was common during the first week of treatment.</AbstractText Results suggest that naltrexone is effective in reducing the symptoms of pathologic gambling. Until further studies corroborate the present findings, our report should be interpreted cautiously.</AbstractText"
]
] |
[
[
"23140422",
"Comparison of GPU- and CPU-implementations of mean-firing rate neural networks on parallel hardware.",
"Modern parallel hardware such as multi-core processors (CPUs) and graphics processing units (GPUs) have a high computational power which can be greatly beneficial to the simulation of large-scale neural networks. Over the past years, a number of efforts have focused on developing parallel algorithms and simulators best suited for the simulation of spiking neural models. In this article, we aim at investigating the advantages and drawbacks of the CPU and GPU parallelization of mean-firing rate neurons, widely used in systems-level computational neuroscience. By comparing OpenMP, CUDA and OpenCL implementations towards a serial CPU implementation, we show that GPUs are better suited than CPUs for the simulation of very large networks, but that smaller networks would benefit more from an OpenMP implementation. As this performance strongly depends on data organization, we analyze the impact of various factors such as data structure, memory alignment and floating precision. We then discuss the suitability of the different hardware depending on the networks' size and connectivity, as random or sparse connectivities in mean-firing rate networks tend to break parallel performance on GPUs due to the violation of coalescence.</AbstractText"
]
] |
23177656
|
Synthetic event-related potentials: a computational bridge between neurolinguistic models and experiments.
|
Our previous work developed Synthetic Brain Imaging to link neural and schema network models of cognition and behavior to PET and fMRI studies of brain function. We here extend this approach to Synthetic Event-Related Potentials (Synthetic ERP). Although the method is of general applicability, we focus on ERP correlates of language processing in the human brain. The method has two components: Phase 1: To generate cortical electro-magnetic source activity from neural or schema network models; and Phase 2: To generate known neurolinguistic ERP data (ERP scalp voltage topographies and waveforms) from putative cortical source distributions and activities within a realistic anatomical model of the human brain and head. To illustrate the challenges of Phase 2 of the methodology, spatiotemporal information from Friederici's 2002 model of auditory language comprehension was used to define cortical regions and time courses of activation for implementation within a forward model of ERP data. The cortical regions from the 2002 model were modeled using atlas-based masks overlaid on the MNI high definition single subject cortical mesh. The electromagnetic contribution of each region was modeled using current dipoles whose position and orientation were constrained by the cortical geometry. In linking neural network computation via EEG forward modeling to empirical results in neurolinguistics, we emphasize the need for neural network models to link their architecture to geometrically sound models of the cortical surface, and the need for conceptual models to refine and adopt brain-atlas based approaches to allow precise brain anchoring of their modules. The detailed analysis of Phase 2 sets the stage for a brief introduction to Phase 1 of the program, including the case for a schema-theoretic approach to language production and perception presented in detail elsewhere. Unlike Dynamic Causal Modeling (DCM) and Bojak's mean field model, Synthetic ERP builds on models of networks that mediate the relation between the brain's inputs, outputs, and internal states in executing a specific task. The neural networks used for Synthetic ERP must include neuroanatomically realistic placement and orientation of the cortical pyramidal neurons. These constraints pose exciting challenges for future work in neural network modeling that is applicable to systems and cognitive neuroscience.</AbstractText
|
[
[
"17691351",
"An introduction to operative neuromodulation and functional neuroprosthetics, the new frontiers of clinical neuroscience and biotechnology.",
"Operative neuromodulation is the field of altering electrically or chemically the signal transmission in the nervous system by implanted devices in order to excite, inhibit or tune the activities of neurons or neural networks and produce therapeutic effects. It is a rapidly evolving biomedical and high-technology field on the cutting-edge of developments across a wide range of scientific disciplines. The authors review relevant literature on the neuromodulation procedures that are performed in the spinal cord or peripheral nerves in order to treat a considerable number of conditions such as (a) chronic pain (craniofacial, somatic, pelvic, limb, or due to failed back surgery), (b) spasticity (due to spinal trauma, multiple sclerosis, upper motor neuron disease, dystonia, cerebral palsy, cerebrovascular disease or head trauma), (c) respiratory disorders, (d) cardiovascular ischemia, (e) neuropathic bladder, and (f) bowel dysfunction of neural cause. Functional neuroprosthetics, a field of operative neuromodulation, encompasses the design, construction and implantation of artificial devices capable of generating electrical stimuli, thereby, replacing the function of damaged parts of the nervous system. The present article also reviews important literature on functional neuroprostheses, functional electrical stimulation (FES), and various emerging applications based on microsystems devices, neural engineering, neuroaugmentation, neurostimulation, and assistive technologies. The authors highlight promising lines of research such as endoneural prostheses for peripheral nerve stimulation, closed-loop systems for responsive neurostimulation or implanted microwires for microstimulation of the spinal cord to enable movements of paralyzed limbs. The above growing scientific fields, in combination with biological regenerative methods, are certainly going to enhance the practice of neuromodulation. The range of neuromodulatory procedures in the spine and peripheral nerves and the dynamics of the biomedical and technological domains which are reviewed in this article indicate that new breakthroughs are likely to improve substantially the quality of life of patients who are severely disabled by neurological disorders.</AbstractText"
]
] |
[
[
"23269439",
"The p.Ala510Val mutation in the SPG7 (paraplegin) gene is the most common mutation causing adult onset neurogenetic disease in patients of British ancestry.",
"The c.1529C >T change in the SPG7 gene, encoding the mutant p.Ala510Val paraplegin protein, was first described as a polymorphism in 1998. This was based on its frequency of 3 % and 4 % in two separate surveys of controls in the United Kingdom (UK) population. Subsequently, it has been found to co-segregate with disease in a number of different populations. Yeast expression studies support its having a deleterious effect. In this paper a consanguineous sibship is described in which four members who are homozygous for the p.Ala510Val variant present with a spectrum of disease. This spectrum encompasses moderately severe hereditary spastic paraparesis (HSP) with more minor ataxia in two siblings, moderately severe ataxia without spasticity in the third, and a very mild gait ataxia in the fourth. Two of the siblings also manifest vestibular failure. The remaining eight unaffected siblings are either heterozygous for the p.Ala510Val variant, or do not carry it at all. Homozygosity mapping using a high-density SNP array across the whole genome found just 11 genes (on two regions of chromosome 3) outside the SPG7 region on chromosome 16, which were homozygously shared by the affected siblings, but not shared by the unaffected siblings; none of them are likely to be causative. The weight of evidence is strongly in favour of the p.Ala510Val variant being a disease-causing mutation. We present additional data from the Auckland City Hospital neurogenetics clinic to show that the p.Ala510Val mutation is prevalent amongst HSP patients of UK extraction belying any suggestion that European p.Ala510Val haplotypes harbour a disease-causing mutation which the UK p.Ala510Val haplotypes do not. Taken together with previous findings of a carrier frequency of 3-4 % in the UK population (giving a homozygosity rate of 20-40/100,000), the data imply that the p.Ala510Val is the most common mutation causing neurogenetic disease in adults of UK ancestry, albeit the penetrance may be low or the disease caused may be mild.</AbstractText"
]
] |
22814704
|
Inflammation in anxiety.
|
The idea of the existence of an interaction between the immune system and the central nervous system (CNS) has prompted extensive research interest into the subject of "Psychoneuroimmunology" taking the field to an interesting level where new hypotheses are being increasingly tested. Specifically, exactly how the cross talk of pathways and mechanisms enable immune system to influence our brain and behavior is a question of immense significance. Of particular relevance to this topic is the role of cytokines in regulating functions within the CNS that ultimately modulate behavior. Interestingly, psychological stress is reported to modulate cytokine production, suggesting potential relevance of this mediator to mental health. In fact, cytokine signaling in the brain is known to regulate important brain functions including neurotransmitter metabolism, neuroendocrine function, synaptic plasticity, as well as the neural circuitry of mood. It is rather obvious to expect an aberrant behavioral outcome as a result of a dysregulation in cytokine signaling which might lead to occurrence of depression, anxiety, and cognitive dysfunction. Thus, understanding the mechanisms by which the immune system influences behavior would reveal targets for potential therapeutic development as well as strategies for the prevention of neuropsychiatric diseases. To date, the presence of inflammatory responses and the crucial role of cytokines in depression have received most attention. However, considering a big socioeconomic impact due to an alarming increase in anxiety disorder patients, there is an urgent research need for a better understanding of the role of cytokines in anxiety. In this review, we discuss recent research on the role of neuroimmunology in anxiety. At the end, we offer an "oxidative stress theory," which we propose works perhaps as a "sensor of distress," the imbalance of which leads to neuroinflammation and causes anxiety disorders. Much research is needed to extensively test this theory keeping an open mind!</AbstractText
|
[
[
"17670965",
"Cell type-specific tuning of hippocampal interneuron firing during gamma oscillations in vivo.",
"Cortical gamma oscillations contribute to cognitive processing and are thought to be supported by perisomatic-innervating GABAergic interneurons. We performed extracellular recordings of identified interneurons in the hippocampal CA1 area of anesthetized rats, revealing that the firing patterns of five distinct interneuron types are differentially correlated to spontaneous gamma oscillations. The firing of bistratified cells, which target dendrites of pyramidal cells coaligned with the glutamatergic input from hippocampal area CA3, is strongly phase locked to field gamma oscillations. Parvalbumin-expressing basket, axo-axonic, and cholecystokinin-expressing interneurons exhibit moderate gamma modulation, whereas the spike timing of distal dendrite-innervating oriens-lacunosum moleculare interneurons is not correlated to field gamma oscillations. Cholecystokinin-expressing interneurons fire earliest in the gamma cycle, a finding that is consistent with their suggested function of thresholding individual pyramidal cells. Furthermore, we show that field gamma amplitude correlates with interneuronal spike-timing precision and firing rate. Overall, our recordings suggest that gamma synchronization in vivo is assisted by temporal- and domain-specific GABAergic inputs to pyramidal cells and is initiated in pyramidal cell dendrites in addition to somata and axon initial segments.</AbstractText"
]
] |
[
[
"22986407",
"How a common variant in the growth factor receptor gene, NTRK1, affects white matter.",
"Growth factors and their receptors are important for cellular migration as well as axonal guidance and myelination in the brain. They also play a key role in programmed cell death, and are implicated in a number of mental illnesses. Recently, we reported that healthy young adults who carry the T allele variant in the growth factor gene, NTRK1 (at location rs6336), had lower white matter integrity than non-carriers on diffusion images of the brain. Diffusion tensor imaging (DTI) revealed how this single nucleotide polymorphism affects white matter microstructure in human populations; DTI is also used to identify characteristic features of brain connectivity in typically developing children and in patients. Newly discovered links between neuroimaging measures and growth factors whose molecular neuroscience is well known offer an important step in understanding mechanisms that contribute to brain connectivity. Altered fiber connectivity may mediate the relationship between some genetic risk factors and a variety of mental illnesses.</AbstractText"
]
] |
23226198
|
Formal comparison of dual-parameter temporal discounting models in controls and pathological gamblers.
|
Temporal or delay discounting refers to the phenomenon that the value of a reward is discounted as a function of time to delivery. A range of models have been proposed that approximate the shape of the discount curve describing the relationship between subjective value and time. Recent evidence suggests that more than one free parameter may be required to accurately model human temporal discounting data. Nonetheless, many temporal discounting studies in psychiatry, psychology and neuroeconomics still apply single-parameter models, despite their oftentimes poor fit to single-subject data. Previous comparisons of temporal discounting models have either not taken model complexity into account, or have overlooked particular models. Here we apply model comparison techniques in a large sample of temporal discounting datasets using several discounting models employed in the past. Among the models examined, an exponential-power model from behavioural economics (CS model, Ebert & Prelec 2007) provided the best fit to human laboratory discounting data. Inter-parameter correlations for the winning model were moderate, whereas they were substantial for other dual-parameter models examined. Analyses of previous group and context effects on temporal discounting with the winning model provided additional theoretical insights. The CS model may be a useful tool in future psychiatry, psychology and neuroscience work on inter-temporal choice.</AbstractText
|
[
[
"12951145",
"Structure and function of the vomeronasal system: an update.",
"Several developments during the past 15 years have profoundly affected our understanding of the vomeronasal system (VNS) of vertebrates. In the mid 1990s, the vomeronasal epithelium of mammals was found to contain two populations of receptor cells, based on their expression of G-proteins. These two populations of neurons were subsequently found to project their axons to different parts of the accessory olfactory bulb (AOB), forming the basis of segregated pathways with possibly heterogeneous functions. A related discovery was the cloning of members of at least two gene families of putative vomeronasal G-protein-coupled receptors (GPRs) in the vomeronasal epithelium. Ligand binding to these receptors was found to activate a phospholipase C (PLC)-dependent signal transduction pathway that primarily involves an increase in intracellular inositol-tris-phosphate and intracellular calcium. In contrast to what was previously believed, neuron replacement in the vomeronasal epithelium appears to occur through a process of vertical migration in most mammals. New anatomical studies of the central pathways of the olfactory and vomeronasal systems indicated that these two systems converge on neurons in the telencephalon, providing an anatomical substrate for functional interactions. Combined anatomical, physiological and behavioral studies in mice provided new information that furthered our understanding of one of the most striking pheromonal phenomena, the Bruce effect. Finally, contrary to prior observations, new anatomical studies indicated that a vomeronasal organ (VNO) was present in human adults and reports were published indicating that this system might be functional. These latter observations are still controversial and require confirmation from independent laboratories.</AbstractText"
]
] |
[
[
"23195123",
"Text-mining and neuroscience.",
"The wealth and diversity of neuroscience research are inherent characteristics of the discipline that can give rise to some complications. As the field continues to expand, we generate a great deal of data about all aspects, and from multiple perspectives, of the brain, its chemistry, biology, and how these affect behavior. The vast majority of research scientists cannot afford to spend their time combing the literature to find every article related to their research, nor do they wish to spend time adjusting their neuroanatomical vocabulary to communicate with other subdomains in the neurosciences. As such, there has been a recent increase in the amount of informatics research devoted to developing digital resources for neuroscience research. Neuroinformatics is concerned with the development of computational tools to further our understanding of the brain and to make sense of the vast amount of information that neuroscientists generate (French & Pavlidis, 2007). Many of these tools are related to the use of textual data. Here, we review some of the recent developments for better using the vast amount of textual information generated in neuroscience research and publication and suggest several use cases that will demonstrate how bench neuroscientists can take advantage of the resources that are available.</AbstractText"
]
] |
22960226
|
Empiricists are from Venus, modelers are from Mars: Reconciling experimental and computational approaches in cognitive neuroscience.
|
We describe how computational models can be useful to cognitive and behavioral neuroscience, and discuss some guidelines for deciding whether a model is useful. We emphasize that because instantiating a cognitive theory as a computational model requires specification of an explicit mechanism for the function in question, it often produces clear and novel behavioral predictions to guide empirical research. However, computational modeling in cognitive and behavioral neuroscience remains somewhat rare, perhaps because of misconceptions concerning the use of computational models (in particular, connectionist models) in these fields. We highlight some common misconceptions, each of which relates to an aspect of computational models: the problem space of the model, the level of biological organization at which the model is formulated, and the importance (or not) of biological plausibility, parsimony, and model parameters. Careful consideration of these aspects of a model by empiricists, along with careful delineation of them by modelers, may facilitate communication between the two disciplines and promote the use of computational models for guiding cognitive and behavioral experiments.</AbstractText
|
[
[
"19120115",
"Chronic stress, combined with a high-fat/high-sugar diet, shifts sympathetic signaling toward neuropeptide Y and leads to obesity and the metabolic syndrome.",
"In response to stress, some people lose while others gain weight. This is believed to be due to either increased beta-adrenergic activation, the body's main fat-burning mechanism, or increased intake of sugar- and fat-rich \"comfort foods.\" A high-fat, high-sugar (HFS) diet alone, however, cannot account for the epidemic of obesity, and chronic stress alone tends to lower adiposity in mice. Here we discuss how chronic stress, when combined with an HFS diet, leads to abdominal obesity by releasing a sympathetic neurotransmitter, neuropeptide Y (NPY), directly into the adipose tissue. In vitro, when \"stressed\" with dexamethasone, sympathetic neurons shift toward expressing more NPY, which stimulates endothelial cell (angiogenesis) and preadipocyte proliferation, differentiation, and lipid-filling (adipogenesis) by activating the same NPY-Y2 receptors (Y2Rs). In vivo, chronic stress, consisting of cold water or aggression in HFS-fed mice, stimulates the release of NPY and the expression of Y2Rs in visceral fat, increasing its growth by 50% in 2 weeks. After 3 months, this results in metabolic syndrome-like symptoms with abdominal obesity, inflammation, hyperlipidemia, hyperinsulinemia, glucose intolerance, hepatic steatosis, and hypertension. Remarkably, local intra-fat Y2R inhibition pharmacologically or via adenoviral Y2R knock-down reverses or prevents fat accumulation and metabolic complications. These studies demonstrated for the first time that chronic stress, via the NPY-Y2R pathway, amplifies and accelerates diet-induced obesity and the metabolic syndrome. Our findings also suggest the use of local administration of Y2R antagonists for treatment of obesity and NPY-Y2 agonists for fat augmentation in other clinical applications.</AbstractText"
]
] |
[
[
"23476081",
"Framing Nicotine Addiction as a \"Disease of the Brain\": Social and Ethical Consequences.",
"In this article, we seek to better understand how a genomic vision of addiction may influence drug prevention and treatment. Though <i We explore the emerging view of addiction as a \"disease of the brain\" in open-ended interviews with 86 stakeholders from the fields of nicotine research and tobacco control. Interview data were analyzed using standard qualitative techniques.</AbstractText Most stakeholders hold a medicalized view of addiction. Though environmental variables are understood to be a primary cause of smoking initiation, the speed and strength with which addiction occurs is understood to be a largely biological process. Though stakeholders believe that an increased focus on addiction as a disease of the brain is not likely to lead to widespread unrealistic expectations for cessation therapies, they remain concerned that it may reinforce teenagers' expectations that quitting is not difficult. Finally, stakeholder responses indicate that genetic and neuroscientific research is unlikely to increase or decrease stigmatization, but will be used by interest groups to buttress their existing views of the stigma associated with smoking.</AbstractText We argue that the main potential harms of focusing on biological etiology stem from a concept of addiction that is disassociated from social context. Focusing on genetic testing and brain scans may lead one to overemphasize pharmaceutical \"magic bullet cures\" and underemphasize, and underfund, more traditional therapies and public health prevention strategies that have proven to be effective. Genetic research on addiction may fundamentally change our conception of deviance and our identities, and may thus transform our susceptibility to substance use into something isolated in our biology, not embedded in a biosocial context.</AbstractText"
]
] |
23267340
|
Social working memory: neurocognitive networks and directions for future research.
|
Navigating the social world requires the ability to maintain and manipulate information about people's beliefs, traits, and mental states. We characterize this capacity as social working memory (SWM). To date, very little research has explored this phenomenon, in part because of the assumption that general working memory systems would support working memory for social information. Various lines of research, however, suggest that social cognitive processing relies on a neurocognitive network (i.e., the "mentalizing network") that is functionally distinct from, and considered antagonistic with, the canonical working memory network. Here, we review evidence suggesting that demanding social cognition requires SWM and that both the mentalizing and canonical working memory neurocognitive networks support SWM. The neural data run counter to the common finding of parametric decreases in mentalizing regions as a function of working memory demand and suggest that the mentalizing network can support demanding cognition, when it is demanding social cognition. Implications for individual differences in social cognition and pathologies of social cognition are discussed.</AbstractText
|
[
[
"16482083",
"Antipsychotic effects on prepulse inhibition in normal 'low gating' humans and rats.",
"Development of new antipsychotics and their novel applications may be facilitated through the use of physiological markers in clinically normal individuals. Both genetic and neurochemical evidence suggests that reduced prepulse inhibition of startle (PPI) may be a physiological marker for individuals at-risk for schizophrenia, and the ability of antipsychotics to normalize PPI may reflect properties linked to their clinical efficacy. We assessed the effects of the atypical antipsychotic quetiapine (12.5 mg p.o.) on PPI in 20 normal men with a 'low PPI' trait, based on PPI levels in the lowest 25% of a normal PPI distribution. The effects of quetiapine (7.5 mg/kg s.c.) on PPI were then assessed in rats with phenotypes of high PPI (Sprague Dawley (SD)) and low PPI (Brown Norway (BN)); effects of clozapine (7.5 mg/kg i.p.) and haloperidol (0.1 mg/kg s.c.) on PPI were also tested in SD rats. At a time of maximal psychoactivity, quetiapine significantly enhanced PPI to short prepulse intervals (20-30 ms) in 'low gating' human subjects. Quetiapine increased PPI in low gating BN rats for prepulse intervals <120 ms; this effect of quetiapine was limited to 20 ms prepulse intervals in SD rats, who also exhibited this pattern in response to clozapine but not haloperidol. In both humans and rats, normal 'low gating' appears to be an atypical antipsychotic-sensitive phenotype. PPI at short intervals may be most sensitive to pro-gating effects of these drugs.</AbstractText"
]
] |
[
[
"22922354",
"Selective interactions of spinophilin with the C-terminal domains of the δ- and μ-opioid receptors and G proteins differentially modulate opioid receptor signaling.",
"Previous studies have shown that the intracellular domains of opioid receptors serve as platforms for the formation of a multi-component signaling complex consisting of various interacting partners (Leontiadis et al., 2009, Cell Signal. 21, 1218-1228; Georganta et al., 2010, Neuropharmacology, 59(3), 139-148). In the present study we demonstrate that spinophilin a dendritic-spine enriched scaffold protein associates with δ- and μ-opioid receptors (δ-ΟR, μ-OR) constitutively in HEK293 an interaction that is altered upon agonist administration and enhanced upon forskolin treatment for both μ-OR and δ-ΟR. Spinophilin association with the opioid receptors is mediated via the third intracellular loop and a conserved region of the C-terminal tails. The portion of spinophilin responsible for interaction with the δ-OR and μ-OR is narrowed to a region encompassing amino acids 151-444. Spinophilin, RGS4, Gα and Gβγ subunits of G proteins form a multi-protein complex using specific regions of spinophilin and a conserved amino acid stretch of the C-terminal tails of both δ-μ-ORs. Expression of spinophilin in HEK293 cells potentiated DPDPE-mediated adenylyl-cyclase inhibition of δ-OR leaving unaffected the levels of cAMP accumulation mediated by the μ-OR. Moreover, measurements of extracellular signal regulated kinase (ERK1,2) phosphorylation indicated that the presence of spinophilin attenuated agonist-driven ERK1,2 phosphorylation mediated upon activation of the δ-OR but not the μ-OR. Collectively, these findings suggest that spinophilin associates with both δ- and μ-ΟR and G protein subunits in HEK293 cells participating in a multimeric signaling complex that displays a differential regulatory role in opioid receptor signaling.</AbstractText"
]
] |
19654141
|
Neuroanthropology: a humanistic science for the study of the culture-brain nexus.
|
In this article, we argue that a combined anthropology/neuroscience field of enquiry can make a significant and distinctive contribution to the study of the relationship between culture and the brain. This field, which can appropriately be termed as neuroanthropology, is conceived of as being complementary to and mutually informative with social and cultural neuroscience. We start by providing an introduction to the culture concept in anthropology. We then present a detailed characterization of neuroanthropology and its methods and how they relate to the anthropological understanding of culture. The field is described as a humanistic science, that is, a field of enquiry founded on the perceived epistemological and methodological interdependence of science and the humanities. We also provide examples that illustrate the proposed methodological model for neuroanthropology. We conclude with a discussion about specific contributions the field can make to the study of the culture-brain nexus.</AbstractText
|
[
[
"19400719",
"The science of neural interface systems.",
"The ultimate goal of neural interface research is to create links between the nervous system and the outside world either by stimulating or by recording from neural tissue to treat or assist people with sensory, motor, or other disabilities of neural function. Although electrical stimulation systems have already reached widespread clinical application, neural interfaces that record neural signals to decipher movement intentions are only now beginning to develop into clinically viable systems to help paralyzed people. We begin by reviewing state-of-the-art research and early-stage clinical recording systems and focus on systems that record single-unit action potentials. We then address the potential for neural interface research to enhance basic scientific understanding of brain function by offering unique insights in neural coding and representation, plasticity, brain-behavior relations, and the neurobiology of disease. Finally, we discuss technical and scientific challenges faced by these systems before they are widely adopted by severely motor-disabled patients.</AbstractText"
]
] |
[
[
"25205899",
"Neuroepidemiology of epilepsy in northwest India.",
"Epilepsy has a complex etiology characterised by recurring seizures.</AbstractText To study clinical profile of epilepsy patients with reference to type of epilepsy in northwest India. No previous Indian study has reported relative incidence of various types of seizures with reference to type of epilepsy.</AbstractText Data of 400 epilepsy patients (200 idiopathic and 200 symptomatic) was collected for their clinical characteristics. The classification of epilepsy into idiopathic and symptomatic types was done on the basis of findings of EEG, CT scan and MRI tests.</AbstractText The age of onset of seizures was less than 15 years in only one third of the total patients. The number of non-vegetarians was higher in SE (68.5%) than IE (58%). The male to female ratio was significantly higher (1.33:1 in IE and 1.47:1 in SE). No difference was seen for place of residence (urban vs rural) patients with epilepsy (PWE). The majority of patients (58.5% of symptomatic and 52.8% idiopathic) though reported no triggering factors, yet many of them, when questioned, had held supernatural powers to be the cause of the disease. Sleep deprivation was reported as a major triggering factor by 28.5% of idiopathic epilepsy (IE) and 25% of symptomatic epilepsy (SE) patients. The incidence of mental retardation (1.25%) and behavioral disorders (7%) was found to be relatively low. Loss of memory was reported in 46% of IE and 43.5% of SE and poor scholastic performance in 23% of IE and 16.5% of SE. A positive history was recorded in 11% first-degree relatives and 4% second-degree relatives. Generalized seizures were more common in IE patients (67.5%), while partial seizures with and without secondary generalization (50.5%), and generalized seizures (49.5%) were equally common in SE.</AbstractText The study demonstrates differences in the type of seizures between idiopathic and symptomatic epilepsies and not other demographic, clinical and psycho-social traits. The males were found to have higher risk of epilepsy than females. The epidemiological characteristics of epileptics show variations across populations and also within population.</AbstractText Hyperornithinemia-hyperammonemia-homocitrullinuria (HHH) syndrome is a disorder of the urea cycle and ornithine degradation pathway. Clinical manifestations and age of onset vary among individuals even in the same family. <i The biochemical diagnosis of HHH syndrome is established in a proband with the classic metabolic triad of episodic or postprandial hyperammonemia, persistent hyperornithinemia, and urinary excretion of homocitrulline. The molecular diagnosis of HHH syndrome is established in a symptomatic individual with or without suggestive metabolic/biochemical findings by identification of biallelic pathogenic variants in <i <i HHH syndrome is inherited in an autosomal recessive manner. At conception, each sib of an affected individual has a 25% chance of being affected, a 50% chance of being an asymptomatic carrier, and a 25% chance of being unaffected and not a carrier. Once the <i"
]
] |
19943188
|
Fast Kalman filtering on quasilinear dendritic trees.
|
Optimal filtering of noisy voltage signals on dendritic trees is a key problem in computational cellular neuroscience. However, the state variable in this problem-the vector of voltages at every compartment-is very high-dimensional: realistic multicompartmental models often have on the order of N = 10(4) compartments. Standard implementations of the Kalman filter require O(N (3)) time and O(N (2)) space, and are therefore impractical. Here we take advantage of three special features of the dendritic filtering problem to construct an efficient filter: (1) dendritic dynamics are governed by a cable equation on a tree, which may be solved using sparse matrix methods in O(N) time; and current methods for observing dendritic voltage (2) provide low SNR observations and (3) only image a relatively small number of compartments at a time. The idea is to approximate the Kalman equations in terms of a low-rank perturbation of the steady-state (zero-SNR) solution, which may be obtained in O(N) time using methods that exploit the sparse tree structure of dendritic dynamics. The resulting methods give a very good approximation to the exact Kalman solution, but only require O(N) time and space. We illustrate the method with applications to real and simulated dendritic branching structures, and describe how to extend the techniques to incorporate spatially subsampled, temporally filtered, and nonlinearly transformed observations.</AbstractText
|
[
[
"11222789",
"Paraplegin gene analysis in hereditary spastic paraparesis (HSP) pedigrees in northeast England.",
"To identify the frequency and characterize the phenotype of paraplegin mutations in the hereditary spastic paraparesis (HSP) population in the northeast of England.</AbstractText HSP is a disorder that shows both clinical and genetic heterogeneity. To date, 13 loci have been associated with an HSP phenotype, with the causative gene having been identified in four of these. Two autosomal genes have been identified, paraplegin and spastin, and two X-linked genes have been identified, L1CAM (cell adhesion molecule) and proteolipid protein.</AbstractText Thirty HSP pedigrees from the northeast of England were analyzed for mutation in each of the 17 exons of the paraplegin gene.</AbstractText A single family with a paraplegin mutation was identified in which the paraplegin mutation co-segregates with an HSP phenotype in an apparent dominant manner. The authors also describe frequent polymorphism in the paraplegin gene in both the HSP and control populations.</AbstractText Mutations in the paraplegin gene are not a common cause of HSP in the northeast of England. The phenotype of the paraplegin-related HSP family described had several striking features including amyotrophy, raised creatine kinase, sensorimotor peripheral neuropathy, and oxidative phosphorylation defect on muscle biopsy.</AbstractText"
]
] |
[
[
"20826300",
"Neuroscience and education: an ideal partnership for producing evidence-based solutions to Guide 21(st) Century Learning.",
"Neuro-Education is a nascent discipline that seeks to blend the collective fields of neuroscience, psychology, cognitive science, and education to create a better understanding of how we learn and how this information can be used to create more effective teaching methods, curricula, and educational policy. Though still in its infancy as a research discipline, this initiative is already opening critical new dialog between teachers, administrators, parents, and brain scientists.</AbstractText"
]
] |
23365838
|
Simultaneous ODF estimation and tractography in HARDI.
|
We consider the problem of tracking white matter fibers in high angular resolution diffusion imaging (HARDI) data while simultaneously estimating the local fiber orientation profile. Prior work showed that an unscented Kalman filter (UKF) can be used for this problem, yet existing algorithms employ parametric mixture models to represent water diffusion and to define the state space. To address this restrictive model dependency, we propose to extend the UKF to HARDI data modeled by orientation distribution functions (ODFs), a more generic diffusion model. We consider the spherical harmonic representation of the HARDI signal as the state, enforce nonnegativity of the ODFs, and perform tractography using the directions at which the ODFs attain their peaks. In simulations, our method outperforms filtered two-tensor tractography at different levels of noise by achieving a reduction in mean Chamfer error of 0.05 to 0.27 voxels; it also produced in vivo fiber tracking that is consistent with the neuroanatomy.</AbstractText
|
[
[
"15831717",
"Resting microglial cells are highly dynamic surveillants of brain parenchyma in vivo.",
"Microglial cells represent the immune system of the mammalian brain and therefore are critically involved in various injuries and diseases. Little is known about their role in the healthy brain and their immediate reaction to brain damage. By using in vivo two-photon imaging in neocortex, we found that microglial cells are highly active in their presumed resting state, continually surveying their microenvironment with extremely motile processes and protrusions. Furthermore, blood-brain barrier disruption provoked immediate and focal activation of microglia, switching their behavior from patroling to shielding of the injured site. Microglia thus are busy and vigilant housekeepers in the adult brain.</AbstractText"
]
] |
[
[
"23542825",
"Neuroanatomy of Cornudescoides kulkarnii n. sp., a gill parasite of Mystus vittatus in Meerut (UP), India.",
"Chemical named 5-bromo indoxyl acetate has been used to describe the nervous system of a viviparous monogenean Cornudescoides Kulkarni (1969), a gill parasite of Mystus vittatus. Central nervous system consists of paired cerebral ganglia from which anterior and posterior neuronal pathways arise. These neuronal pathways are interlinked by cross connectives and commissures. Paired dorsal, ventral and lateral nerve cords emanate from the cerebral ganglia, connected at intervals by transverse connectives. Huge arrangement of dorsal, ventral and lateral nerve cords and their innervations have been examined. Peripheral nervous system (PNS) includes innervations of the alimentary tract, reproductive organs and attachment organs (anterior adhesive areas and haptor). Both the CNS and PNS are bilaterally symmetrical, and better developed ventrally than laterally and dorsally.</AbstractText"
]
] |
23926462
|
Neurogenetics and Nutrigenomics of Neuro-Nutrient Therapy for Reward Deficiency Syndrome (RDS): Clinical Ramifications as a Function of Molecular Neurobiological Mechanisms.
|
In accord with the new definition of addiction published by American Society of Addiction Medicine (ASAM) it is well-known that individuals who present to a treatment center involved in chemical dependency or other documented reward dependence behaviors have impaired brain reward circuitry. They have hypodopaminergic function due to genetic and/or environmental negative pressures upon the reward neuro-circuitry. This impairment leads to aberrant craving behavior and other behaviors such as Substance Use Disorder (SUD). Neurogenetic research in both animal and humans revealed that there is a well-defined cascade in the reward site of the brain that leads to normal dopamine release. This cascade has been termed the "Brain Reward Cascade" (BRC). Any impairment due to either genetics or environmental influences on this cascade will result in a reduced amount of dopamine release in the brain reward site. Manipulation of the BRC has been successfully achieved with neuro-nutrient therapy utilizing nutrigenomic principles. After over four decades of development, neuro-nutrient therapy has provided important clinical benefits when appropriately utilized. This is a review, with some illustrative case histories from a number of addiction professionals, of certain molecular neurobiological mechanisms which if ignored may lead to clinical complications.</AbstractText
|
[
[
"15663891",
"Orexin A promotes histamine, but not norepinephrine or serotonin, release in frontal cortex of mice.",
"To investigate the effects of orexin A on release of histamine, norepinephrine, and serotonin in the frontal cortex of mice.</AbstractText Samples for measuring histamine, norepinephrine, and serotonin contents were collected by in vivo microdialysis of the frontal cortex of anesthetized mice. The histamine, noradrenaline, and serotonin content in dialysates were measured by HPLC techniques.</AbstractText Intracrebroventricular injection of orexin A at doses of 12.5, 50, and 200 pmol per mouse promoted histamine release from the frontal cortex in a dose-dependent manner. At the highest dose given, 200 pmol, orexin A significantly induced histamine release, with the maximal magnitude being 230% over the mean basal release. The enhanced histamine release was sustained for 140 min, and then gradually returned to the basal level. However, no change in norepinephrine or serotonin release was observed under application of the same dose of orexin A.</AbstractText These results suggest that the arousal effect of orexin A is mainly mediated by histamine, not by norepinephrine or serotonin.</AbstractText"
]
] |
[
[
"23060781",
"Using \"smart stimulators\" to treat Parkinson's disease: re-engineering neurostimulation devices.",
"Let's imagine the cruise control of your car locked at 120 km/h on any road in any condition (city, country, highway, sunny or rainy weather), or your car air conditioner set on maximum cold in any temperature condition (even during a snowy winter): would you find it efficient? That would probably not be the most optimal strategy for a proper and comfortable driving experience. As surprising as this may seem, this is a pretty accurate illustration of how deep brain stimulation is used today to treat Parkinson's disease motor symptoms and other neurological disorders such as essential tremor, obsessive-compulsive disorder, or epilepsy.</AbstractText"
]
] |
22639700
|
Mitochondrial DNA: A Blind Spot in Neuroepigenetics.
|
Neuroepigenetics, which includes nuclear DNA modifications such as 5-methylcytosine and 5-hydoxymethylcytosine and modifications of nuclear proteins such as histones, is emerging as the leading field in molecular neuroscience. Historically, a functional role for epigenetic mechanisms, including in neuroepigenetics, has been sought in the area of the regulation of nuclear transcription. However, one important compartment of mammalian cell DNA, different from nuclear but equally important for physiological and pathological processes (including in the brain), mitochondrial DNA has for the most part not had a systematic epigenetic characterization. The importance of mitochondria and mitochondrial DNA (particularly its mutations) in central nervous system physiology and pathology has long been recognized. Only recently have mechanisms of mitochondrial DNA methylation and hydroxymethylation, including the discovery of mitochondrial DNA-methyltransferases and the presence and the functionality of 5-methylcytosine and 5-hydroxymethylcytosine in mitochondrial DNA (e.g., in modifying the transcription of mitochondrial genome), been unequivocally recognized as a part of mammalian mitochondrial physiology. Here we summarize for the first time evidence supporting the existence of these mechanisms and we propose the term "mitochondrial epigenetics" to be used when referring to them. Currently, neuroepigenetics does not include mitochondrial epigenetics - a gap that we expect to close in the near future.</AbstractText
|
[
[
"8490989",
"Epidemiology of epilepsy in developing countries.",
"Epilepsy is an important health problem in developing countries, where its prevalence can be up to 57 per 1000 population. This article reviews the epidemiology of epilepsy in developing countries in terms of its incidence, prevalence, seizure type, mortality data, and etiological factors. The prevalence of epilepsy is particularly high in Latin America and in several African countries, notably Liberia, Nigeria, and the United Republic of Tanzania. Parasitic infections, particularly neurocysticercosis, are important etiological factors for epilepsy in many of these countries. Other reasons for the high prevalence include intracranial infections of bacterial or viral origin, perinatal brain damage, head injuries, toxic agents, and hereditary factors. Many of these factors are, however, preventable or modifiable, and the introduction of appropriate measures to achieve this could lead to a substantial decrease in the incidence of epilepsy in developing countries.</AbstractText"
]
] |
[
[
"23366028",
"Transcranial direct current stimulation in pediatric brain: a computational modeling study.",
"Transcranial direct current stimulation (tDCS) is a method of non-invasive brain stimulation which uses weak electric currents applied on the scalp to modulate activity of underlying brain tissue. In addition to being used as a tool for cognitive neuroscience investigations, tDCS has generated considerable interest for use as a therapeutic modality for neurologic disorders. Though the safety and tolerability of tDCS in adults is well-established, there is little information on the safety of tDCS in children. Because there are differences between children and adults in several key parameters (such as skull thickness and cerebrospinal fluid volume) which affect current flow through the brain, special consideration should be given to the stimulation parameters which are used in a pediatric study population. In this study we present cortical electrical field maps at different stimulation intensities and electrode configurations using a high-resolution-MRI derived finite element model of a typically developing, anatomically normal 12 year old child. The peak electrical fields for a given stimulus intensity in the adolescent brain were twice as high as in the adult brain for conventional tDCS and nearly four times as high for a 4X1 High-Definition tDCS electrode configuration. These data suggest that acceptable tDCS stimulation parameters may be different in children compared to adults, and that further modeling studies are needed to help guide decisions about applied current intensity.</AbstractText"
]
] |
23366028
|
Transcranial direct current stimulation in pediatric brain: a computational modeling study.
|
Transcranial direct current stimulation (tDCS) is a method of non-invasive brain stimulation which uses weak electric currents applied on the scalp to modulate activity of underlying brain tissue. In addition to being used as a tool for cognitive neuroscience investigations, tDCS has generated considerable interest for use as a therapeutic modality for neurologic disorders. Though the safety and tolerability of tDCS in adults is well-established, there is little information on the safety of tDCS in children. Because there are differences between children and adults in several key parameters (such as skull thickness and cerebrospinal fluid volume) which affect current flow through the brain, special consideration should be given to the stimulation parameters which are used in a pediatric study population. In this study we present cortical electrical field maps at different stimulation intensities and electrode configurations using a high-resolution-MRI derived finite element model of a typically developing, anatomically normal 12 year old child. The peak electrical fields for a given stimulus intensity in the adolescent brain were twice as high as in the adult brain for conventional tDCS and nearly four times as high for a 4X1 High-Definition tDCS electrode configuration. These data suggest that acceptable tDCS stimulation parameters may be different in children compared to adults, and that further modeling studies are needed to help guide decisions about applied current intensity.</AbstractText
|
[
[
"12721816",
"Dopamine D3 receptor gene polymorphism and violent behavior: relation to impulsiveness and ADHD-related psychopathology.",
"Several lines of evidence indicate that dopaminergic neurotransmission is involved in the regulation of impulsive aggression and violence and that genetically determined variability in dopaminergic gene expression modifies complex traits including that of impulsivity and aggression. In this study we report an association of the dopamine D3 receptor (DRD3) polymorphism with impulsiveness according to Eysenck's EIQ and scores on the German short version of the Wender Utah Rating Scale (WURS-k), which we used for the assessment of a history of ADHD-related symptoms. This association was detected in a group of violent offenders, but not in non-violent individuals. Highest scores of EIQ impulsiveness and of the WURS-k were found in heterozygous violent individuals, while homozygotes showed significant lower rating scores, suggesting an heterosis effect. The results of our study suggest that variations of the DRD3 gene are likely involved in the regulation of impulsivity and some psychopathological aspects of ADHD related to violent behavior.</AbstractText"
]
] |
[
[
"23202064",
"Three-dimensional multiwaveguide probe array for light delivery to distributed brain circuits.",
"To deliver light to the brain for neuroscientific and neuroengineering applications like optogenetics, in which light is used to activate or silence neurons expressing specific photosensitive proteins, optical fibers are commonly used. However, an optical fiber is limited to delivering light to a single target within the 3D structure of the brain. Here, we describe the design and fabrication of an array of thin microwaveguides, which terminates at a three-dimensionally distributed set of points, appropriate for delivering light to targets distributed in a 3D pattern throughout the brain.</AbstractText"
]
] |
23504543
|
Bio-amplifier with Driven Shield Inputs to Reduce Electrical Noise and its Application to Laboratory Teaching of Electrophysiology.
|
We describe a custom-designed bio-amplifier and its use in teaching neurophysiology to undergraduate students. The amplifier has the following features: 1) differential amplification with driven shield inputs, which makes it workable even in electrically unshielded environments, 2) high input impedance to allow recordings of small signals through high signal source impedance, 3) dual fixed frequency bandpass filters (1-340Hz for surface EMG, EEG, local field potential etc and 320Hz - 3.4kHz for neuronal action potential recording) and independent gain controllers (up to x107,000) to allow the recording of different signals from the same source (e.g., local field potential and spiking activity of neurons), and 4) printed circuit board technology for easy replication with consistent quality. We compared its performance with a commercial amplifier in an electrically noisy environment. Even without any electrostatic shield, it recorded clear electromyographic activity with little interference from other electric appliances. In contrast, the commercial amplifier's performance severely deteriorated under the same condition. We used this amplifier to build a computer-controlled stimulation and measurement system for electroencephalographic recordings by undergraduate students. The students successfully recorded various sensory evoked potentials with clarity that otherwise would have required costly instruments. This amplifier is a low-cost yet reliable instrument for electro-physiological recording both in education and research.</AbstractText
|
[
[
"21386006",
"Optogenetics in the teaching laboratory: using channelrhodopsin-2 to study the neural basis of behavior and synaptic physiology in Drosophila.",
"Here we incorporate recent advances in Drosophila neurogenetics and \"optogenetics\" into neuroscience laboratory exercises. We used the light-activated ion channel channelrhodopsin-2 (ChR2) and tissue-specific genetic expression techniques to study the neural basis of behavior in Drosophila larvae. We designed and implemented exercises using inexpensive, easy-to-use systems for delivering blue light pulses with fine temporal control. Students first examined the behavioral effects of activating glutamatergic neurons in Drosophila larvae and then recorded excitatory junctional potentials (EJPs) mediated by ChR2 activation at the larval neuromuscular junction (NMJ). Comparison of electrically and light-evoked EJPs demonstrates that the amplitudes and time courses of light-evoked EJPs are not significantly different from those generated by electrical nerve stimulation. These exercises introduce students to new genetic technology for remotely manipulating neural activity, and they simplify the process of recording EJPs at the Drosophila larval NMJ. Relatively little research work has been done using ChR2 in Drosophila, so students have opportunities to test novel hypotheses and make tangible contributions to the scientific record. Qualitative and quantitative assessment of student experiences suggest that these exercises help convey principles of synaptic transmission while also promoting integrative and inquiry-based studies of genetics, cellular physiology, and animal behavior.</AbstractText"
]
] |
[
[
"22958820",
"How variable clones build an invariant retina.",
"A fundamental question in developmental neuroscience is how a collection of progenitor cells proliferates and differentiates to create a brain of the appropriate size and cellular composition. To address this issue, we devised lineage-tracing assays in developing zebrafish embryos to reconstruct entire retinal lineage progressions in vivo and thereby provide a complete quantitative map of the generation of a vertebrate CNS tissue from individual progenitors. These lineage data are consistent with a simple model in which the retina is derived from a set of equipotent retinal progenitor cells (RPCs) that are subject to stochastic factors controlling lineage progression. Clone formation in mutant embryos reveals that the transcription factor Ath5 acts as a molecular link between fate choice and mode of cell division, giving insight into the elusive molecular mechanisms of histogenesis, the conserved temporal order by which neurons of different types exit the cell cycle.</AbstractText"
]
] |
22557965
|
An ontological approach to describing neurons and their relationships.
|
The advancement of neuroscience, perhaps one of the most information rich disciplines of all the life sciences, requires basic frameworks for organizing the vast amounts of data generated by the research community to promote novel insights and integrated understanding. Since Cajal, the neuron remains a fundamental unit of the nervous system, yet even with the explosion of information technology, we still have few comprehensive or systematic strategies for aggregating cell-level knowledge. Progress toward this goal is hampered by the multiplicity of names for cells and by lack of a consensus on the criteria for defining neuron types. However, through umbrella projects like the Neuroscience Information Framework (NIF) and the International Neuroinformatics Coordinating Facility (INCF), we have the opportunity to propose and implement an informatics infrastructure for establishing common tools and approaches to describe neurons through a standard terminology for nerve cells and a database (a Neuron Registry) where these descriptions can be deposited and compared. This article provides an overview of the problem and outlines a solution approach utilizing ontological characterizations. Based on illustrative implementation examples, we also discuss the need for consensus criteria to be adopted by the research community, and considerations on future developments. A scalable repository of neuron types will provide researchers with a resource that materially contributes to the advancement of neuroscience.</AbstractText
|
[
[
"17049754",
"Behavioral impulsivity predicts treatment outcome in a smoking cessation program for adolescent smokers.",
"To examine the relationship between impulsivity and smoking cessation treatment response among adolescents.</AbstractText Thirty adolescent smokers participated in a high school based smoking cessation program combining contingency management and cognitive behavioral therapy. Self-report (Barratt impulsiveness scale (BIS-II); Kirby delay discounting measure (DDM)) and behavioral (experiential discounting task (EDT); continuous performance task (CPT)) measures of impulsivity were assessed at treatment onset.</AbstractText Sixteen participants (53%) were abstinent from smoking at completion of the four-week study. Compared to abstinent adolescents, those not achieving abstinence discounted monetary rewards more on the EDT and committed more commission errors on the CPT. Group differences were not observed on the BIS-II or DDM.</AbstractText These preliminary results suggest that specific behavioral measures of impulsivity may be associated with the ability to initiate and/or maintain abstinence from smoking among adolescent smokers.</AbstractText"
]
] |
[
[
"23130007",
"When Do We Confuse Self and Other in Action Memory? Reduced False Memories of Self-Performance after Observing Actions by an Out-Group vs. In-Group Actor.",
"Observing another person performing an action can lead to a false memory of having performed the action oneself - the observation-inflation effect. In the experimental paradigm, participants first perform or do not perform simple actions, and then observe another person perform some of these actions. The observation-inflation effect is found when participants later remember performing actions that they have merely observed. In this case, self and other are confused in action memory. We examined social conditions of this self-other confusion when remembering actions, specifically whether the effect depends on the observed actor's group membership. In our experiment, we manipulated group membership based on physical appearance, specifically complexion of the hands. Fair-skinned participants observed either an in-group (i.e., fair-skinned) or an out-group (i.e., dark-skinned) actor. Our results revealed that the observed actor's group membership moderated the observation-inflation effect: False memories were significantly reduced when the actor was from the out-group (vs. in-group). We found no difference to a control condition in which the actor wore black gloves, suggesting that distinctiveness of perceptual or sensory features alone (due to the out-group member's dark skin) is not critical. We discuss these findings in light of social-neuroscience studies demonstrating the impact of an observed person's group membership on motor simulation. Overall, our findings suggest that action memory can be affected by a ubiquitous feature of people's social perception, that is, group-based social categorization of others.</AbstractText"
]
] |
23504612
|
An undergraduate laboratory exercise examining the psychomotor stimulant effects of caffeine in laboratory rats.
|
This paper describes an exercise in a Systems and Behavioral Neuroscience with Laboratory class, an introductory laboratory class taken by Barnard College students majoring in a wide range of academic topics. The study took place over three weeks, allowing students to assess the effects of caffeine on motor stimulation in laboratory rats. The within-subject design involved injecting rats with three different caffeine doses and measuring five different motor outputs in a standard open field. Students completed four different assignments related to this study, demonstrating acquisition of the stated learning goals. This lab exercise allowed students to learn about basal ganglia neural circuitry and stimulant pharmacology, to work directly with an animal model, and to generate enough data to perform statistical analyses. Course evaluations suggest that students liked learning about caffeine, a stimulant many of them have personal experience consuming. They also expressed appreciation for working with rats and for learning how to analyze data. This study can easily be implemented at most undergraduate institutions under minimal cost. The wide-ranging effects of caffeine also permit for flexibility in experimental design, allowing instructors and students options for different avenues of investigation.</AbstractText
|
[
[
"17940025",
"Short-term meditation training improves attention and self-regulation.",
"Recent studies suggest that months to years of intensive and systematic meditation training can improve attention. However, the lengthy training required has made it difficult to use random assignment of participants to conditions to confirm these findings. This article shows that a group randomly assigned to 5 days of meditation practice with the integrative body-mind training method shows significantly better attention and control of stress than a similarly chosen control group given relaxation training. The training method comes from traditional Chinese medicine and incorporates aspects of other meditation and mindfulness training. Compared with the control group, the experimental group of 40 undergraduate Chinese students given 5 days of 20-min integrative training showed greater improvement in conflict scores on the Attention Network Test, lower anxiety, depression, anger, and fatigue, and higher vigor on the Profile of Mood States scale, a significant decrease in stress-related cortisol, and an increase in immunoreactivity. These results provide a convenient method for studying the influence of meditation training by using experimental and control methods similar to those used to test drugs or other interventions.</AbstractText"
]
] |
[
[
"22925211",
"Developmental neurotoxicity testing: scientific approaches towards the next generation to protect the developing nervous system of children. An overview of the Developmental Neurotoxicity Symposium in 2011.",
"The Developmental Neurotoxicology (DNT) Committee has been working to promote developmental neurotoxicology and related scientific areas of interest to integrate academic and regulatory sciences in this field since the Behavioral Teratology Meeting was established by the Japanese Teratology Society in 1982. The committee has led several large-scale collaborative studies to standardize existing methodologies and held symposiums and workshops periodically at the society's annual meetings. This overview provides a history of the DNT Committee, as well as a brief summary of the DNT Symposium in 2011.</AbstractText"
]
] |
22977368
|
Coping with Brain Disorders using Neurotechnology.
|
Brain disorders account for more than 34% of the global burden of disease, crippling nations by decreasing their "mental capital"-with greater effect in developing countries. Early detection is the key to their management, but establishing such programmes seems nearly impossible due to the high prevalence of the dysfunctions as compared with the high cost of neuroimaging devices. Thus, at first sight, the research of the Decade of the Brain and the international Human Brain Mapping Project might seem to be condemned to benefit only a small elite. Cuba has shown that is not so by using neurotechnology for the last 3 decades to implement stratified active screening programmes for brain disorders at the population level. This experience has shown that, by the transformation of health indicators, an appropriate use of technology can be integrated with attention to the population at the primary levels of both health care and education. An essential component of neurotechnology is neuroinformatics, which-like its counterpart bioinformatics-combines databases, analysis tools, and theoretical models to craft tools for early disease diagnosis and management. Much work remains to be done and will depend critically on south-south cooperation to solve problems for countries with similar situations.</AbstractText
|
[
[
"12716950",
"Hierarchical processing in spoken language comprehension.",
"Understanding spoken language requires a complex series of processing stages to translate speech sounds into meaning. In this study, we use functional magnetic resonance imaging to explore the brain regions that are involved in spoken language comprehension, fractionating this system into sound-based and more abstract higher-level processes. We distorted English sentences in three acoustically different ways, applying each distortion to varying degrees to produce a range of intelligibility (quantified as the number of words that could be reported) and collected whole-brain echo-planar imaging data from 12 listeners using sparse imaging. The blood oxygenation level-dependent signal correlated with intelligibility along the superior and middle temporal gyri in the left hemisphere and in a less-extensive homologous area on the right, the left inferior frontal gyrus (LIFG), and the left hippocampus. Regions surrounding auditory cortex, bilaterally, were sensitive to intelligibility but also showed a differential response to the three forms of distortion, consistent with sound-form-based processes. More distant intelligibility-sensitive regions within the superior and middle temporal gyri, hippocampus, and LIFG were insensitive to the acoustic form of sentences, suggesting more abstract nonacoustic processes. The hierarchical organization suggested by these results is consistent with cognitive models and auditory processing in nonhuman primates. Areas that were particularly active for distorted speech conditions and, thus, might be involved in compensating for distortion, were found exclusively in the left hemisphere and partially overlapped with areas sensitive to intelligibility, perhaps reflecting attentional modulation of auditory and linguistic processes.</AbstractText"
]
] |
[
[
"23110153",
"Prediction of muscle activities from electrocorticograms in primary motor cortex of primates.",
"Electrocorticography (ECoG) has drawn attention as an effective recording approach for brain-machine interfaces (BMI). Previous studies have succeeded in classifying movement intention and predicting hand trajectories from ECoG. Despite such successes, however, there still remains considerable work for the realization of ECoG-based BMIs as neuroprosthetics. We developed a method to predict multiple muscle activities from ECoG measurements. We also verified that ECoG signals are effective for predicting muscle activities in time varying series when performing sequential movements. ECoG signals were band-pass filtered into separate sensorimotor rhythm bands, z-score normalized, and smoothed with a Gaussian filter. We used sparse linear regression to find the best fit between frequency bands of ECoG and electromyographic activity. The best average correlation coefficient and the normalized root-mean-square error were 0.92±0.06 and 0.06±0.10, respectively, in the flexor digitorum profundus finger muscle. The δ (1.5∼4Hz) and γ2 (50∼90Hz) bands contributed significantly more strongly than other frequency bands (P<0.001). These results demonstrate the feasibility of predicting muscle activity from ECoG signals in an online fashion.</AbstractText"
]
] |
23420996
|
The fundamental role of morphology in experimental neurotoxicology: the example of chemotherapy-induced peripheral neurotoxicity.
|
The peripheral nervous system is a frequent target of toxic agents. The accurate identification of the sites of neurotoxic action through the morphological characterization of reliable in vivo models or in vitro systems can give fundamental clues when investigating the pathogenesis and interpreting the clinical features of drug-induced neuropathy. The morphological approach has been used to investigate almost all the anticancer drugs able to induce chemotherapy-induced peripheral neurotoxicity, i.e. platinum drugs, antitubulins and proteasome inhibitors. No models have ever been described for thalidomide. This review demonstrates that any pathogenetic study on chemotherapy-induced peripheral neurotoxicity must be based on solid morphological observations obtained in reliable animal and in vitro models. This is particularly true in this setting, since the availability of tissues of human origin is extremely limited. In fact, peripheral (generally sural) nerve biopsies are never required for diagnostic purposes in chemotherapy-treated cancer patients, and their use for a purely scientific aim, although potentially very informative, is not ethical. Moreover, several neurotoxic drugs target the dorsal root ganglia neurons, and it is very difficult to obtain high-quality specimens even from early autopsies. It is, therefore, our opinion that an extensive morphological assessment of the in vitro and in vivo effect of any potentially neurotoxic antineoplastic drugs, as well as of neuroprotectant agents, should be taken into consideration right from the earliest stages of their development.</AbstractText
|
[
[
"22430310",
"Cloning and expression of tachykinins and their association with kisspeptins in the brains of zebrafish.",
"The tachykinins are a family of neuropeptides, including substance P (SP), neurokinin A (NKA), and neurokinin B (NKB), that are encoded by the tac1 (SP and NKA) or tac2/3 (NKB) genes. Tachykinins are widely distributed in the central nervous system and have roles as neurotransmitters and/or neuromodulators. Recent studies in mammals have demonstrated the coexpression of NKB and kisspeptin and their comodulatory roles over the control of reproduction. We have recently identified two kisspeptin-encoding genes, kiss1 and kiss2, in teleosts. However, such relationship between tachykinins and kisspeptins has not been demonstrated in non-mammalian species. To determine the involvement of tachykinins in the reproduction in teleosts, we identified tac1 and two tac2 (tac2a and tac2b) sequences in the zebrafish genome using in silico data mining. Zebrafish tac1 encodes SP and NKA, whereas the tac2 sequences encode NKB and an additional peptide homologous to NKB (NKB-related peptide). Digoxigenin in situ hybridization in the brain of zebrafish showed tac1 mRNA-containing cells in the olfactory bulb, telencephalon, preoptic region, hypothalamus, mesencephalon, and rhombencephalon. The zebrafish tac2a mRNA-containing cells were observed in the preoptic region, habenula, and hypothalamus, whereas the tac2b mRNA-containing cells were predominantly observed in the dorsal telencephalic area. Furthermore, we examined the coexpression of tachykinins and two kisspeptin genes in the brain of zebrafish. Dual fluorescent in situ hybridization showed no coexpression of tachykinins mRNA with kisspeptins mRNA in hypothalamic nuclei or the habenula. These results suggest the presence of independent pathways for kisspeptins and NKB neurons in the brain of zebrafish.</AbstractText"
]
] |
[
[
"23010511",
"Transcriptome analysis of Drosophila CNS midline cells reveals diverse peptidergic properties and a role for castor in neuronal differentiation.",
"One of the key aspects of neuronal differentiation is the array of neurotransmitters and neurotransmitter receptors that each neuron possesses. One important goal of developmental neuroscience is to understand how these differentiated properties are established during development. In this paper, we use fluorescence activated cell sorting and RNA-seq to determine the transcriptome of the Drosophila CNS midline cells, which consist of a small number of well-characterized neurons and glia. These data revealed that midline cells express 9 neuropeptide precursor genes, 13 neuropeptide receptor genes, and 31 small-molecule neurotransmitter receptor genes. In situ hybridization and high-resolution confocal analyses were carried-out to determine the midline cell identity for these neuropeptides and the neuropeptide receptors. The results revealed a surprising level of diversity. Neuropeptide genes are expressed in a variety of midline cell types, including motoneurons, GABAergic interneurons, and midline glia. These data revealed previously unknown functional differences among the highly-related iVUM neurons. There also exist segmental differences in expression for the same neuronal sub-type. Similar experiments on midline-expressed neuropeptide receptor genes reveal considerable diversity in synaptic inputs. Multiple receptor types were expressed in midline interneurons and motoneurons, and, in one case, link feeding behavior to gut peristalsis and locomotion. There were also segmental differences, variations between the 3 iVUMs, and three hormone receptor genes were broadly expressed in most midline cells. The Drosophila Castor transcription factor is present at high levels in iVUM5, which is both GABAergic and expresses the short neuropeptide F precursor gene. Genetic and misexpression experiments indicated that castor specifically controls expression of the short neuropeptide F precursor gene, but does not affect iVUM cell fate or expression of Gad1. This indicates a novel function for castor in regulating neuropeptide gene expression.</AbstractText"
]
] |
23142960
|
Current concept of neuromyelitis optica (NMO) and NMO spectrum disorders.
|
Neuromyelitis optica (NMO) has been described as a disease clinically characterised by severe optic neuritis (ON) and transverse myelitis (TM). Other features of NMO include female preponderance, longitudinally extensive spinal cord lesions (>3 vertebral segments), and absence of oligoclonal IgG bands . In spite of these differences from multiple sclerosis (MS), the relationship between NMO and MS has long been controversial. However, since the discovery of NMO-IgG or aquaporin-4 (AQP4) antibody (AQP4-antibody), an NMO-specific autoantibody to AQP4, the dominant water channel in the central nervous system densely expressed on end-feet of astrocytes, unique clinical features, MRI and other laboratory findings in NMO have been clarified further. AQP4-antibody is now the most important laboratory finding for the diagnosis of NMO. Apart from NMO, some patients with recurrent ON or recurrent longitudinally extensive myelitis alone are also often positive for AQP4-antibody. Moreover, studies of AQP4-antibody-positive patients have revealed that brain lesions are not uncommon in NMO, and some patterns appear to be unique to NMO. Thus, the spectrum of NMO is wider than mere ON and TM. Pathological analyses of autopsied cases strongly suggest that unlike MS, astrocytic damage is the primary pathology in NMO, and experimental studies confirm the pathogenicity of AQP4-antibody. Importantly, therapeutic outcomes of some immunological treatments are different between NMO and MS, making early differential diagnosis of these two disorders crucial. We provide an overview of the epidemiology, clinical and neuroimaging features, immunopathology and therapy of NMO and NMO spectrum disorders.</AbstractText
|
[
[
"22304908",
"Immune cells exploit a neural circuit to enter the CNS.",
"Multiple sclerosis (MS) is associated with the appearance of autoreactive T cells in the central nervous system. Using a mouse model of MS, Arima et al. now show that this attack begins at a specific spinal cord location. T cell entry into the CNS is regulated by a reflex neural circuit originating from leg muscle contractions.</AbstractText"
]
] |
[
[
"23010509",
"Using mouse models of autism spectrum disorders to study the neurotoxicology of gene-environment interactions.",
"To better study the role of genetics in autism, mouse models have been developed which mimic the genetics of specific autism spectrum and related disorders. These models have facilitated research on the role genetic susceptibility factors in the pathogenesis of autism in the absence of environmental factors. Inbred mouse strains have been similarly studied to assess the role of environmental agents on neurodevelopment, typically without the complications of genetic heterogeneity of the human population. What has not been as actively pursued, however, is the methodical study of the interaction between these factors (e.g., gene and environmental interactions in neurodevelopment). This review suggests that a genetic predisposition paired with exposure to environmental toxicants plays an important role in the etiology of neurodevelopmental disorders including autism, and may contribute to the largely unexplained rise in the number of children diagnosed with autism worldwide. Specifically, descriptions of the major mouse models of autism and toxic mechanisms of prevalent environmental chemicals are provided followed by a discussion of current and future research strategies to evaluate the role of gene and environment interactions in neurodevelopmental disorders.</AbstractText"
]
] |
20797539
|
Spatiotemporal response properties of optic-flow processing neurons.
|
A central goal in sensory neuroscience is to fully characterize a neuron's input-output relation. However, strong nonlinearities in the responses of sensory neurons have made it difficult to develop models that generalize to arbitrary stimuli. Typically, the standard linear-nonlinear models break down when neurons exhibit stimulus-dependent modulations of their gain or selectivity. We studied these issues in optic-flow processing neurons in the fly. We found that the neurons' receptive fields are fully described by a time-varying vector field that is space-time separable. Increasing the stimulus strength, however, strongly reduces the neurons' gain and selectivity. To capture these changes in response behavior, we extended the linear-nonlinear model by a biophysically motivated gain and selectivity mechanism. We fit all model parameters directly to the data and show that the model now characterizes the neurons' input-output relation well over the full range of motion stimuli.</AbstractText
|
[
[
"11253062",
"Association study designs for complex diseases.",
"Assessing the association between DNA variants and disease has been used widely to identify regions of the genome and candidate genes that contribute to disease. However, there are numerous examples of associations that cannot be replicated, which has led to skepticism about the utility of the approach for common conditions. With the discovery of massive numbers of genetic markers and the development of better tools for genotyping, association studies will inevitably proliferate. Now is the time to consider critically the design of such studies, to avoid the mistakes of the past and to maximize their potential to identify new components of disease.</AbstractText"
]
] |
[
[
"22958820",
"How variable clones build an invariant retina.",
"A fundamental question in developmental neuroscience is how a collection of progenitor cells proliferates and differentiates to create a brain of the appropriate size and cellular composition. To address this issue, we devised lineage-tracing assays in developing zebrafish embryos to reconstruct entire retinal lineage progressions in vivo and thereby provide a complete quantitative map of the generation of a vertebrate CNS tissue from individual progenitors. These lineage data are consistent with a simple model in which the retina is derived from a set of equipotent retinal progenitor cells (RPCs) that are subject to stochastic factors controlling lineage progression. Clone formation in mutant embryos reveals that the transcription factor Ath5 acts as a molecular link between fate choice and mode of cell division, giving insight into the elusive molecular mechanisms of histogenesis, the conserved temporal order by which neurons of different types exit the cell cycle.</AbstractText"
]
] |
22958820
|
How variable clones build an invariant retina.
|
A fundamental question in developmental neuroscience is how a collection of progenitor cells proliferates and differentiates to create a brain of the appropriate size and cellular composition. To address this issue, we devised lineage-tracing assays in developing zebrafish embryos to reconstruct entire retinal lineage progressions in vivo and thereby provide a complete quantitative map of the generation of a vertebrate CNS tissue from individual progenitors. These lineage data are consistent with a simple model in which the retina is derived from a set of equipotent retinal progenitor cells (RPCs) that are subject to stochastic factors controlling lineage progression. Clone formation in mutant embryos reveals that the transcription factor Ath5 acts as a molecular link between fate choice and mode of cell division, giving insight into the elusive molecular mechanisms of histogenesis, the conserved temporal order by which neurons of different types exit the cell cycle.</AbstractText
|
[
[
"9222381",
"Molecular mimicry between HIV-1 gp41 and an astrocyte isoform of alpha-actinin.",
"A 100-kDa astrocyte antigen previously shown to cross-react with a monoclonal antibody (MAb) generated against amino acids (aa) 598 to 609 of the transmembrane protein gp41 of human immunodeficiency virus type 1 [HIV-1] has now been molecularly characterized and found to be an alpha-actinin (alpha-actinin) related protein. Western blot analyses of human astrocytoma cells fractionated by differential centrifugation and detergent phase separation showed that the antigen was membrane associated. The astrocyte protein was purified to apparent homogeneity by immunoaffinity chromatography. Amino acid analysis of three peptide fragments obtained by cleavage of the purified 100-kDa protein revealed sequence identities of 77, 83 and 100% to a non-muscle isoform of human alpha-actinin. In addition, the aa 598-609 sequence of gp41 recognized by MAb 781.4, and the aa 581-597 sequence recognized by another cross-reactive MAb 781.3, were 73% and 53% similar to regions of alpha-actinin. This molecular mimicry between gp41 and alpha-actinin was supported by antibody cross-reactivity in Western immunoblot and ELISA analyses. Both anti-gp41 and anti-alpha-actinin MAbs bind to the surface of the human astrocytoma cells as detected by a cell surface binding assay and immunofluorescence. Antibodies made against this immunodominant region of gp41 in the serum and CSF of HIV-infected individuals have access to astrocytes within the CNS. The identification of the astrocyte antigen as an alpha-actinin related protein will allow further work to determine how this immunological cross-reactivity could perturb astrocyte function and contribute to HIV neuropathology.</AbstractText"
]
] |
[
[
"23227112",
"A Social Neuroscience Perspective on Stress and Health.",
"Psychological stress is a major risk factor for the development and progression of a number of diseases, including cardiovascular disease, cancer, arthritis, and major depression. A growing body of research suggests that long-term, stress-induced activation of the sympathetic nervous system (SNS) and the hypothalamic-pituitary-adrenal (HPA) axis may lead to increases in inflammation, which is known to play a key role in the pathophysiology of a variety of diseases. Furthermore, the burgeoning fields of social neuroscience and health neuroscience have begun to identify the neurocognitive mechanisms by which stress may lead to these physiological changes. Here we review the literature examining the neurocognitive correlates of stress-induced SNS, HPA, and inflammatory responses. Specifically, we summarize the results of neuroimaging studies that have examined the neural correlates of stress-related increases in SNS, HPA, and inflammatory activity. A set of neural systems involved in threat processing, safety processing, and social cognition are suggested as key contributors to stress-related changes in physiology. We conclude by offering suggestions for future research in the exciting new field of health neuroscience.</AbstractText"
]
] |
21345429
|
Challenging the supremacy of the frontal lobe: early views (1906-1909) of Christfried Jakob on the human cerebral cortex.
|
This article focuses on a series of six studies that address functional localization in the frontal lobe; they were published in Argentina between 1906 and 1909 by Christfried Jakob (1866-1956), one of the great thinkers in early 20th century neuropathology and neurophilosophy. At that time, the localization-holism controversy was at a peak, having been triggered by the historic Marie-Déjerine aphasiology debate. Jakob held the view that constitutive physiological elements of cognition are localized. Nonetheless, he cast doubt on phrenological approaches that considered the frontal lobe as 'superior' to the other cortical regions. Jakob studied the human frontal lobe from fetal life through senility, in normality and pathology, including tumors, injuries, softening, general paralysis and dementia. Based on those finds, he considered strict localization theories a dead-end. Taking a critical look at Flechsig's ideas on the parallel ontogenies of frontal association centers and intellect, Jakob argued that the frontal lobe does not carry any selective advantage over the remaining human cerebral lobes or even over the frontal lobe in non-human primates. Regarding lesion experiments in laboratory animals, he pointed to methodological caveats, such as insufficient recovery time, that may lead to disorientating conclusions, and rejected élite brain research, calling it superficial and inexact. Jakob was convinced that the verification of the anatomical connections of the frontal lobe would elucidate its functions. Thus, he viewed the frontal lobe as a central station receiving input via olfactory pathways and thalamic radiations, pertinent to muscular and cutaneous senses, and attributed a perceptive character to a brain region traditionally associated with productive functions. Modern neuroscience seems to support Jakob's rejection of distinguishable motor and sensory regions and to adopt a cautious stance concerning oversimplified localization views.</AbstractText
|
[
[
"21896369",
"The size and burden of mental disorders and other disorders of the brain in Europe 2010.",
"To provide 12-month prevalence and disability burden estimates of a broad range of mental and neurological disorders in the European Union (EU) and to compare these findings to previous estimates. Referring to our previous 2005 review, improved up-to-date data for the enlarged EU on a broader range of disorders than previously covered are needed for basic, clinical and public health research and policy decisions and to inform about the estimated number of persons affected in the EU.</AbstractText Stepwise multi-method approach, consisting of systematic literature reviews, reanalyses of existing data sets, national surveys and expert consultations. Studies and data from all member states of the European Union (EU-27) plus Switzerland, Iceland and Norway were included. Supplementary information about neurological disorders is provided, although methodological constraints prohibited the derivation of overall prevalence estimates for mental and neurological disorders. Disease burden was measured by disability adjusted life years (DALY).</AbstractText Prevalence: It is estimated that each year 38.2% of the EU population suffers from a mental disorder. Adjusted for age and comorbidity, this corresponds to 164.8million persons affected. Compared to 2005 (27.4%) this higher estimate is entirely due to the inclusion of 14 new disorders also covering childhood/adolescence as well as the elderly. The estimated higher number of persons affected (2011: 165m vs. 2005: 82m) is due to coverage of childhood and old age populations, new disorders and of new EU membership states. The most frequent disorders are anxiety disorders (14.0%), insomnia (7.0%), major depression (6.9%), somatoform (6.3%), alcohol and drug dependence (>4%), ADHD (5%) in the young, and dementia (1-30%, depending on age). Except for substance use disorders and mental retardation, there were no substantial cultural or country variations. Although many sources, including national health insurance programs, reveal increases in sick leave, early retirement and treatment rates due to mental disorders, rates in the community have not increased with a few exceptions (i.e. dementia). There were also no consistent indications of improvements with regard to low treatment rates, delayed treatment provision and grossly inadequate treatment. Disability: Disorders of the brain and mental disorders in particular, contribute 26.6% of the total all cause burden, thus a greater proportion as compared to other regions of the world. The rank order of the most disabling diseases differs markedly by gender and age group; overall, the four most disabling single conditions were: depression, dementias, alcohol use disorders and stroke.</AbstractText In every year over a third of the total EU population suffers from mental disorders. The true size of \"disorders of the brain\" including neurological disorders is even considerably larger. Disorders of the brain are the largest contributor to the all cause morbidity burden as measured by DALY in the EU. No indications for increasing overall rates of mental disorders were found nor of improved care and treatment since 2005; less than one third of all cases receive any treatment, suggesting a considerable level of unmet needs. We conclude that the true size and burden of disorders of the brain in the EU was significantly underestimated in the past. Concerted priority action is needed at all levels, including substantially increased funding for basic, clinical and public health research in order to identify better strategies for improved prevention and treatment for disorders of the brain as the core health challenge of the 21st century.</AbstractText"
]
] |
[
[
"23110153",
"Prediction of muscle activities from electrocorticograms in primary motor cortex of primates.",
"Electrocorticography (ECoG) has drawn attention as an effective recording approach for brain-machine interfaces (BMI). Previous studies have succeeded in classifying movement intention and predicting hand trajectories from ECoG. Despite such successes, however, there still remains considerable work for the realization of ECoG-based BMIs as neuroprosthetics. We developed a method to predict multiple muscle activities from ECoG measurements. We also verified that ECoG signals are effective for predicting muscle activities in time varying series when performing sequential movements. ECoG signals were band-pass filtered into separate sensorimotor rhythm bands, z-score normalized, and smoothed with a Gaussian filter. We used sparse linear regression to find the best fit between frequency bands of ECoG and electromyographic activity. The best average correlation coefficient and the normalized root-mean-square error were 0.92±0.06 and 0.06±0.10, respectively, in the flexor digitorum profundus finger muscle. The δ (1.5∼4Hz) and γ2 (50∼90Hz) bands contributed significantly more strongly than other frequency bands (P<0.001). These results demonstrate the feasibility of predicting muscle activity from ECoG signals in an online fashion.</AbstractText"
]
] |
23428079
|
Capturing specific abilities as a window into human individuality: the example of face recognition.
|
Proper characterization of each individual's unique pattern of strengths and weaknesses requires good measures of diverse abilities. Here, we advocate combining our growing understanding of neural and cognitive mechanisms with modern psychometric methods in a renewed effort to capture human individuality through a consideration of specific abilities. We articulate five criteria for the isolation and measurement of specific abilities, then apply these criteria to face recognition. We cleanly dissociate face recognition from more general visual and verbal recognition. This dissociation stretches across ability as well as disability, suggesting that specific developmental face recognition deficits are a special case of a broader specificity that spans the entire spectrum of human face recognition performance. Item-by-item results from 1,471 web-tested participants, included as supplementary information, fuel item analyses, validation, norming, and item response theory (IRT) analyses of our three tests: (a) the widely used Cambridge Face Memory Test (CFMT); (b) an Abstract Art Memory Test (AAMT), and (c) a Verbal Paired-Associates Memory Test (VPMT). The availability of this data set provides a solid foundation for interpreting future scores on these tests. We argue that the allied fields of experimental psychology, cognitive neuroscience, and vision science could fuel the discovery of additional specific abilities to add to face recognition, thereby providing new perspectives on human individuality.</AbstractText
|
[
[
"15831717",
"Resting microglial cells are highly dynamic surveillants of brain parenchyma in vivo.",
"Microglial cells represent the immune system of the mammalian brain and therefore are critically involved in various injuries and diseases. Little is known about their role in the healthy brain and their immediate reaction to brain damage. By using in vivo two-photon imaging in neocortex, we found that microglial cells are highly active in their presumed resting state, continually surveying their microenvironment with extremely motile processes and protrusions. Furthermore, blood-brain barrier disruption provoked immediate and focal activation of microglia, switching their behavior from patroling to shielding of the injured site. Microglia thus are busy and vigilant housekeepers in the adult brain.</AbstractText"
]
] |
[
[
"22946114",
"Giuseppe Ferrario and the epidemiology of apoplexy during the 19th century.",
"To analyze the pioneering research of Giuseppe Ferrario (1802-1870) on the epidemiology of apoplexy. To our knowledge, his work might have been the first to systematically investigate the epidemiology of cerebrovascular accidents, with the aim of shedding light on the underlying causes.</AbstractText A detailed analysis of the essay \"Statistics of sudden deaths, more particularly of deaths from apoplexy, in the city and neighborhood of Milan, from 1750 to 1834,\" published by Ferrario in 1834.</AbstractText Ferrario conducted a large retrospective study on 13,360 people who died from apoplexy during an 84-year observational period. Analyzed data showed that these events were more frequent among men and during winter. Apoplexy was reported as mainly occurring at the age of 60; an increase in mortality was observed in young women aged between 21 and 30 years, probably due to an abuse of bloodletting. Ferrario introduced the term \"hereditary apoplexy,\" being one of the first to hypothesize hereditary components in cerebrovascular diseases. He also tried to investigate the role of social conditions in the etiopathogenesis of these events, analyzing marital and employment status and suggesting to his colleagues that cultural and economic factors should be further examined.</AbstractText Giuseppe Ferrario may be considered as a pioneer of modern science and epidemiology and his work deserves consideration within the history of neurology and of neuroepidemiology.</AbstractText"
]
] |
End of preview. Expand
in Data Studio
YAML Metadata
Warning:
empty or missing yaml metadata in repo card
(https://huggingface.co/docs/hub/datasets-cards)
Jerjes/neuro-specter2-sample-data
This dataset contains anchor papers with their top-K most similar (positive) and most dissimilar (negative) papers based on SPECTER2 embeddings.
Dataset Structure
Each row contains:
anchor_id: Unique identifier for the anchor paperanchor_title: Title of the anchor paperanchor_abstract: Abstract of the anchor paperpositive_pool: List of 5 most similar papers, each as [id, title, abstract]negative_pool: List of 5 most dissimilar papers, each as [id, title, abstract]
Dataset Statistics
- Total anchors: 288
- Positives per anchor: 5
- Negatives per anchor: 5
- Embedding model: allenai/specter2_base
Usage
from datasets import load_dataset
dataset = load_dataset("Jerjes/neuro-specter2-sample-data")
# Access a sample
sample = dataset["train"][0]
print(f"Anchor: {sample['anchor_title']}")
print(f"Top positive: {sample['positive_pool'][0][1]}") # title of most similar paper
print(f"Top negative: {sample['negative_pool'][0][1]}") # title of most dissimilar paper
Citation
If you use this dataset, please cite the original SPECTER2 paper:
@inproceedings{specter2,
title={SPECTER2: Better Scientific Paper Representations Through Augmented Word Embeddings},
author={Pradeep Dasigi and Kyle Lo and Iz Beltagy and Arman Cohan and Noah A. Smith and Matt Gardner},
booktitle={Proceedings of the 2021 Conference on Empirical Methods in Natural Language Processing},
year={2021}
}
- Downloads last month
- 3