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Whereas information is what is contained in a message, utterance is how the communication is conducted, and understanding “refers to the distinction between information and utterance” (p. 290). Luhmann’s perspective is a radical departure from traditional communication scholarship. | https://en.wikipedia.org/wiki/Communicative_Constitution_of_Organizations |
Putnam and Fairhurst (2015) explain that the Luhmannian perspective is wholly communicative; that is, meaning is complete up to utterances in a given communicative interaction. Luhmann’s perspective gives less value to human agency in favor of a social agentic perspective. For this reason, Seidl claims that CCO research using Luhmann’s version should focus on communication not on actors. Human agency is minimized by this perspective. Psychic systems (i.e., the mind) interact with social systems (i.e., an organic conglomerate of multiple psychic systems) and human actors are not relevant to the constitution of organizations. | https://en.wikipedia.org/wiki/Communicative_Constitution_of_Organizations |
Six premises are shared by each CCO perspective.Premise 1 is that CCO scholarship looks at communication events. Any “turn of talk, discourse, artifact, metaphor, architectural element, body, text or narrative” is potentially important in producing and reproducing the organization. Premise 2 is that CCO scholarship includes any communicative act in the analysis of organizational communication. That is, macro and micro communication matter in constituting the organization. | https://en.wikipedia.org/wiki/Communicative_Constitution_of_Organizations |
Scholars broadly as “the ongoing, dynamic, interactive process of manipulating symbols toward the creation, maintenance, destruction and/or transformation of meanings which are axial—not peripheral—to organizational existence and organizing phenomena” Premise 3 is that CCO acknowledges the co-constructed/co-oriented nature of communication. Communication is not an individual experience it is an inherently social phenomenon. Meaning is an ongoing, updating, and always social process. | https://en.wikipedia.org/wiki/Communicative_Constitution_of_Organizations |
Premise 4 is that the agent of action (both human and non-human) remains an open question. CCO theory embraces the ability of artifacts to shape the actions of members of the organization. For example, McPhee and Iverson (2009) explore how a communidad in Mexico was able take action against entities threatening land use; in this example, both humans and cattle affect who can own land and how it is used by such an unusual organization. | https://en.wikipedia.org/wiki/Communicative_Constitution_of_Organizations |
Premise 5 is that CCO scholarship does not extend beyond the realm of communication events. This premise suggests what CCO is not:“Something as material and (apparently) inert as a building, for instance, participates in the constitution of an organization through what it does: sheltering operations, channeling activities, impressing visitors, communicating some specific values, norms, and ideologies… Paraphrasing the two Jameses (Dewey and Taylor) it is in communication that such figures will make a difference (or not) through the way their action is negotiated, imposed or debated.”Premise 6 is that CCO favors neither organizing nor organization. That is, in the words of Putnam and Fairhurst (2015), organizations are not just continually becoming they are grounded in action. Further, these premises do not privilege any particular methodology and instead focus on an ontological and epistemological claim. | https://en.wikipedia.org/wiki/Communicative_Constitution_of_Organizations |
A scholarship is a form of financial aid awarded to students for further education. Generally, scholarships are awarded based on a set of criteria such as academic merit, diversity and inclusion, athletic skill, and financial need. Scholarship criteria usually reflect the values and goals of the donor of the award, and while scholarship recipients are not required to repay scholarships, the awards may require that the recipient continue to meet certain requirements during their period of support, such maintaining a minimum grade point average or engaging in a certain activity (e.g., playing on a school sports team for athletic scholarship holders).Scholarships also range in generosity; some cover partial tuition, while others offer a 'full-ride', covering all tuition, accommodation, housing and others. Some prestigious, highly competitive scholarships are well-known even outside the academic community, such as Fulbright Scholarship and the Rhodes Scholarships at the graduate level, and the Robertson, Morehead-Cain and Jefferson Scholarships at the undergraduate level. | https://en.wikipedia.org/wiki/Scholarship |
While the terms scholarship and grant are frequently used interchangeably, they are distinctly different. Where grants are offered based exclusively on financial need, scholarships may have a financial need component but rely on other criteria as well. Academic scholarships typically use a minimum grade-point average or standardized test score such as the ACT or SAT to narrow down awardees. Athletic scholarships are generally based on athletic performance of a student and used as a tool to recruit high-performing athletes for their school's athletic teams. Merit scholarships can be based on a number of criteria, including performance in a particular school subject or club participation or community service.A federal Pell Grant can be awarded to someone planning to receive their undergraduate degree and is solely based on their financial needs. | https://en.wikipedia.org/wiki/Scholarship |
The most common scholarships may be classified as: Merit-based: These awards are based on a student's academic, artistic, athletic, or other abilities, and often a factor in an applicant's extracurricular activities and community service record. Most such merit-based scholarships are paid directly by the institution the student attends, rather than issued directly to the student. Need-based: Some private need-based awards are confusingly called scholarships, and require the results of a FAFSA (the family's expected family contribution). However, scholarships are often merit-based, while grants tend to be need-based. | https://en.wikipedia.org/wiki/Scholarship |
Student-specific: These are scholarships for which applicants must initially qualify based upon gender, race, religion, family, and medical history, or many other student-specific factors. Minority scholarships are the most common awards in this category. For example, students in Canada may qualify for a number of Indigenous scholarships, whether they study at home or abroad. | https://en.wikipedia.org/wiki/Scholarship |
The Gates Millennium Scholars Program is another minority scholarship funded by Bill and Melinda Gates for excellent African American, American Indian, Asian Pacific Islander American, and Latino students who enroll in college. Career-specific: These are scholarships a college or university awards to students who plan to pursue a specific field of study. Often, the most generous awards go to students who pursue careers in high-need areas, such as education or nursing. | https://en.wikipedia.org/wiki/Scholarship |
Many schools in the United States give future nurses full scholarships to enter the field, especially if the student intends to work in a high-need community. College-specific: College-specific scholarships are offered by individual colleges and universities to highly qualified applicants. | https://en.wikipedia.org/wiki/Scholarship |
These scholarships are given on the basis of academic and personal achievement. Some scholarships have a "bond" requirement. Recipients may be required to work for a particular employer for a specified period of time or to work in rural or remote areas; otherwise, they may be required to repay the value of the support they received from the scholarship. | https://en.wikipedia.org/wiki/Scholarship |
This is particularly the case with education and nursing scholarships for people prepared to work in rural and remote areas. The programs offered by the uniformed services of the United States (Army, Navy, Marine Corps, Air Force, Coast Guard, National Oceanic and Atmospheric Administration Commissioned Officer Corps, and Public Health Service Commissioned Corps) sometimes resemble such scholarships. Athletic: Awarded to students with exceptional skill in a sport. | https://en.wikipedia.org/wiki/Scholarship |
Often this is so that the student will be available to attend the school or college and play the sport on their team, although in some countries government funded sports scholarships are available, allowing scholarship holders to train for international representation. School-based athletics scholarships can be controversial, as some believe that awarding scholarship money for athletic rather than academic or intellectual purposes is not in the institution's best interest. Brand: These scholarships are sponsored by a corporation that is trying to gain attention to their brand, or a cause. | https://en.wikipedia.org/wiki/Scholarship |
Sometimes these scholarships are referred to as branded scholarships. The Miss America beauty pageant is a famous example of a brand scholarship. Creative contest: These scholarships are awarded to students based on a creative submission. | https://en.wikipedia.org/wiki/Scholarship |
Contest scholarships are also called mini project-based scholarships, where students can submit entries based on unique and innovative ideas. "Last dollar": can be provided by private and government-based institutions, and are intended to cover the remaining fees charged to a student after the various grants are taken into account. To prohibit institutions from taking last dollar scholarships into account, and thereby removing other sources of funding, these scholarships are not offered until after financial aid has been offered in the form of a letter. Furthermore, last dollar scholarships may require families to have filed taxes for the most recent year, received their other sources of financial aid, and not yet received loans. Open: a scholarship open to any applicant. | https://en.wikipedia.org/wiki/Scholarship |
Chevening Scholarship: Foreign & Commonwealth Office (UK) China Scholarship Council Scholarship: Government of China Commonwealth Scholarship: Commonwealth governments Coca-Cola Scholarship: the Coca-Cola Company Endeavour Awards: Government of Australia Erasmus Mundus: European Union Fulbright Scholarship Gates Cambridge Scholarship: Bill & Melinda Gates Foundation; University of Cambridge Jardine Scholarship: Jardine Matheson; Universities of Oxford and Cambridge Marshall Scholarship: UK universities Mitchell Scholarship: US-Ireland Alliance Morehead-Cain Scholarship: University of North Carolina Foundation Scholarship: Trinity College Dublin Rhodes Scholarship: University of Oxford Schwarzman Scholars: Tsinghua University | https://en.wikipedia.org/wiki/Scholarship |
Dubnow Garden (alternative spelling Dubnov) (Hebrew: גינת דובנוב) is a public park and garden located in the center of Tel Aviv, Israel, lying at the back of the Tel Aviv Performing Arts Center. The park is named for Simon Dubnow, a Jewish Belarusian historian, writer and activist. The street sharing its name (Dubnow Street) makes up the western border of the garden. | https://en.wikipedia.org/wiki/Dubnow_Garden |
Dubnow Garden is very popular with young families, students and dog owners. It contains playgrounds and outdoor exercise equipment. == External links == | https://en.wikipedia.org/wiki/Dubnow_Garden |
Albert Dauzat (French pronunciation: ; 4 July 1877 – 31 October 1955) was a French linguist specializing in toponymy and onomastics.Dauzat, a student of Jules Gilliéron, was a director of studies at the École des hautes études. | https://en.wikipedia.org/wiki/Albert_Dauzat |
L'argot des poilus; dictionnaire humoristique et philologique du langage des soldats de la grande guerre de 1914, 1918 La géographie linguistique, 1922 Les noms de lieux, origine et évolution; villes et villages--pays--cours d'eau--montagnes--lieux-dits, 1926 La Langue Française: sa vie, son évolution, 1926 Les argots: caractères, évolution, influence, 1928 Le génie de la langue française, 1942 Grammaire raisonnée de la langue française, 1947 Dictionnaire étymologique des noms de famille et prénoms de France, 1951 | https://en.wikipedia.org/wiki/Albert_Dauzat |
Miscommunication ("mis" + "communication") is the failure of communicating clearly the intended message or idea. It may be a social inability to communicate adequately and properly, and it is one of many types of communication barriers. It is an instant where either the speaker is unable to provide the proper and adequate information to the hearer or the hearer misperceived and couldn't recognise the communication from the speaker. | https://en.wikipedia.org/wiki/Miscommunication |
The cases of miscommunication vary depending on the situation and persons included in it, but often result in confusion and frustration. In some cases, miscommunication may even open up the triangle of other factors that inevitably leads to a conflict. Miscommunication is a lack of alignment of agents' intellectual state, especially when they diverge on the outcomes of communication. The type of miscommunication can now be classified as to the source of the non-alignment about the communicative act. | https://en.wikipedia.org/wiki/Miscommunication |
Statistical graphics, also known as statistical graphical techniques, are graphics used in the field of statistics for data visualization. | https://en.wikipedia.org/wiki/Statistical_graphics |
Whereas statistics and data analysis procedures generally yield their output in numeric or tabular form, graphical techniques allow such results to be displayed in some sort of pictorial form. They include plots such as scatter plots, histograms, probability plots, spaghetti plots, residual plots, box plots, block plots and biplots.Exploratory data analysis (EDA) relies heavily on such techniques. They can also provide insight into a data set to help with testing assumptions, model selection and regression model validation, estimator selection, relationship identification, factor effect determination, and outlier detection. In addition, the choice of appropriate statistical graphics can provide a convincing means of communicating the underlying message that is present in the data to others.Graphical statistical methods have four objectives: The exploration of the content of a data set The use to find structure in data Checking assumptions in statistical models Communicate the results of an analysis.If one is not using statistical graphics, then one is forfeiting insight into one or more aspects of the underlying structure of the data. | https://en.wikipedia.org/wiki/Statistical_graphics |
Statistical graphics have been central to the development of science and date to the earliest attempts to analyse data. Many familiar forms, including bivariate plots, statistical maps, bar charts, and coordinate paper were used in the 18th century. Statistical graphics developed through attention to four problems: Spatial organization in the 17th and 18th century Discrete comparison in the 18th and early 19th century Continuous distribution in the 19th century and Multivariate distribution and correlation in the late 19th and 20th century.Since the 1970s statistical graphics have been re-emerging as an important analytic tool with the revitalisation of computer graphics and related technologies. | https://en.wikipedia.org/wiki/Statistical_graphics |
Famous graphics were designed by: William Playfair who produced what could be called the first line, bar, pie, and area charts. For example, in 1786 he published the well known diagram that depicts the evolution of England's imports and exports, Florence Nightingale, who used statistical graphics to persuade the British Government to improve army hygiene, John Snow who plotted deaths from cholera in London in 1854 to detect the source of the disease, and Charles Joseph Minard who designed a large portfolio of maps of which the one depicting Napoleon's campaign in Russia is the best known.See the plots page for many more examples of statistical graphics. | https://en.wikipedia.org/wiki/Statistical_graphics |
Brain stimulation reward (BSR) is a pleasurable phenomenon elicited via direct stimulation of specific brain regions, originally discovered by James Olds and Peter Milner. BSR can serve as a robust operant reinforcer. Targeted stimulation activates the reward system circuitry and establishes response habits similar to those established by natural rewards, such as food and sex. Experiments on BSR soon demonstrated that stimulation of the lateral hypothalamus, along with other regions of the brain associated with natural reward, was both rewarding as well as motivation-inducing. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Electrical brain stimulation and intracranial drug injections produce robust reward sensation due to a relatively direct activation of the reward circuitry. This activation is considered to be more direct than rewards produced by natural stimuli, as those signals generally travel through the more indirect peripheral nerves. BSR has been found in all vertebrates tested, including humans, and it has provided a useful tool for understanding how natural rewards are processed by specific brain regions and circuits, as well the neurotransmission associated with the reward system.Intracranial self-stimulation (ICSS) is the operant conditioning method used to produce BSR in an experimental setting. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
ICSS typically involves subjects with permanent electrode implants in one of several regions of the brain known to produce BSR when stimulated. Subjects are trained to continuously respond to electrical stimulation of that brain region. ICSS studies have been particularly useful for examining the effects of various pharmacological manipulations on reward sensitivity. ICSS has been utilized as a means to gauge addiction liability for drugs of many classes, including those that act on monoaminergic, opioid, and cholinergic neurotransmission. These data correlate well with findings from self-administration studies on the addictive properties of drugs. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
In 1953, James Olds and Peter Milner, of McGill University, observed that rats preferred to return to the region of the test apparatus where they received direct electrical stimulation to the septal area of the brain. From this demonstration, Olds and Milner inferred that the stimulation was rewarding, and through subsequent experiments, they confirmed that they could train rats to execute novel behaviors, such as lever pressing, in order to receive short pulse trains of brain stimulation. Olds and Milner discovered the reward mechanisms in the brain involved in positive reinforcement, and their experiments led to the conclusion that electrical stimulation could serve as an operant reinforcer. According to B.F. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Skinner, operant reinforcement occurs when a behavior is followed by the presentation of a stimulus, and it is considered essential to the learning of response habits. Their discovery enabled motivation and reinforcement to be understood in terms of their underlying physiology, and it led to further experimentation to determine the neural basis of reward and reinforcement. Since the initial discovery, the phenomenon of BSR has been demonstrated in all species tested, and Robert Galbraith Heath similarly demonstrated that BSR can be applied to humans.In one oft-cited example, in 1972, Heath's subject known as "B-19" reported "feelings of pleasure, alertness, and warmth" and "protested each time the unit was taken from him, pleading to self-stimulate just a few more times". | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Among ethicists, early "direct brain stimulation" or "psychosurgery" experiments have been criticized as "dubious and precarious (even) by yesterday's standards". In a case published in 1986, a subject who was given the ability to self-stimulate at home ended up ignoring her family and personal hygiene, and spent entire days on electrical self-stimulation. By the time her family intervened, the subject had developed an open sore on her finger from repeatedly adjusting the current. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Early studies on the motivational effects of brain stimulation addressed two primary questions: 1. Which brain sites can be stimulated to produce the perception of reward? and 2. Which drugs influence the response to stimulation and via what mechanism?Investigation of the brain reward circuitry reveals that it consists of a distributed, multi-synaptic circuit that determines both BSR and natural reward function. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The natural drives that motivate and shape behavior reach the reward circuitry trans-synaptically through the peripheral senses of sight, sound, taste, smell, or touch. However, experimentally-induced BSR more directly activates the reward circuitry and bypasses transduction through peripheral sensory pathways. For this reason, electrical brain stimulation provides a tool for identifying the reward circuitry within the central nervous system with some degree of anatomical and neurochemical specificity. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Studies involving these two forms of laboratory reward showed stimulation of a broad range of limbic and diencephalic structures could be rewarding as well as implicated the dopamine-containing neurons of the mesolimbic dopamine system in motivational function. The motivational effect of intracranial self-stimulation varies substantially depending on the placement site of the surgically implanted electrode during electrical stimulation, and animals will work to stimulate different neural sites depending on their current state. Often, animals that work to initiate brain stimulation will also work to terminate the stimulation. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The relationship between BSR and natural rewards (e.g. food, water and copulation) has long been debated, and much of the early research on BSR is focused on their respective similarities and differences. BSR is facilitated through the same reinforcement pathway activated by natural rewards. Self-stimulation can exert robust activation of central reward mechanisms due to more direct action than natural rewards, which initially activate peripheral nerves. BSR to the medial forebrain bundle (MFB) through either electrical or chemical means activates key components of the reward pathway also activated by natural rewards. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
When specific regions of the hypothalamus are electrically stimulated, it elicits reward-related behaviors such as eating, drinking, or copulation responses.Natural rewards are associated with a state of deprivation from unmet needs or desires (e.g., hunger). These states drive instinctual, motivated behaviors like food consumption. It has been argued that this is not the case with BSR, as it does not meet an intrinsic survival-based need. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
BSR also notably lacks an established neural representation in memory that naturally facilitates the learning of reward expectancy. Both of these effects lead to diminished response rate for BSR in the early trials of a series; however, experiments have also shown that extinguished behavior can be quickly reinstated by a priming stimulation that refreshes the short-term association involved in reward expectancy. Studies on BSR indicate that reinforcing brain stimulation may activate the natural pathways associated with natural drives as well as stimulate the reinforcement pathways that are usually activated by natural rewards. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Rats will perform lever-pressing at rates of several thousand responses per hour for days in exchange for direct electrical stimulation of the lateral hypothalamus. Multiple studies have demonstrated that rats will perform reinforced behaviors at the exclusion of all other behaviors. Experiments have shown rats will forgo food to the point of starvation in exchange for brain stimulation or intravenous cocaine when both food and stimulation are offered concurrently for a limited time each day. Rats will also cross electrified grids to press a lever, and they are willing to withstand higher levels of shock to obtain electrical stimulation than to obtain food. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Satiation experiments in rats have revealed that BSR does not produce satiety. Olds demonstrated that this lack of satiation associated with BSR allows animals to self-stimulate to sheer exhaustion and that satiation is dependent on the location of the electrical stimulation. In a 48-hour satiation test, rats with hypothalamic electrodes self-stimulated to exhaustion and showed no intrinsic satiation tendencies, whereas telencephalic electrodes showed radical slowing of self-stimulation after 4 to 8 hours. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The insatiability of BSR is closely related to the strength of drive. While a natural reward, like food, is met with a feeling of being full (satiety), BSR does not have a comparable correlate. This allows for BSR to be experienced indefinitely, or in the case of ICSS, until exhaustion. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Addiction is a chronic brain disorder consisting of compulsive drug-taking and seeking that is maintained despite detrimental effects on various aspects of life including health, relationships, and work. Laboratory procedures can establish compulsive self-administration habits of seeking and ingesting that qualify as addictive behaviors. Rodents and non-human primates have been shown to work in a compulsive manner to receive intravenous injections of stimulants, and when access to the drugs is not limited, they will self-administer drugs to the point of severe weight loss and death. Similar to self-administration behavior, responding for intracranial brain stimulation has a highly compulsive component characteristic of an addicted state. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
BSR is hypothesized to be so effective in establishing compulsive habits due to its more direct activation of the reward pathway, bypassing transmission through sensory pathways in response to natural rewards. Delayed reinforcement following a response for BSR decreases how strongly this behavior is reinforced and to what extent it continues. A delay of one second, for example, between a lever-press and reward delivery (stimulation) can reduce response levels. BSR offers insights into the neural circuitry involved in reinforcement and compulsive behavior. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Mapping and lesion studies on BSR were designed to determine the location of reward-relevant neurons as well as determine the signal pathways that are directly affected by brain stimulation. The site of intracranial self-stimulation leads to substantially different behavioral characteristics. Sites along the length of the medial forebrain bundle (MFB) through the lateral and posterior hypothalamus, the ventral tegmental area (VTA), and into the pons are associated with the strongest reward effects of stimulation. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The lateral hypothalamus is a portion of the hypothalamus, and brain stimulation to this area at the level of the medial forebrain bundle produces the highest response rates and subsequently the highest reward potency in rodents. Lesions in this region or along its boundary cause a loss of positive drive-reward behaviors as well as all other operant drive behaviors. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The medial forebrain bundle (MFB) is the location of the most frequently investigated brain stimulation reward sites, and it is composed of a complex bundle of axons projecting from the basal olfactory regions and the septal nuclei. MFB is not the sole anatomical substrate responsible for reinforcing brain stimulation; however, it is the main tract for the ascending dopamine fibers, and it functions to relay information from the VTA to the nucleus accumbens. The rewarding effect of MFB stimulation is mediated via the activation of the mesocorticolimbic dopamine system. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The mesolimbic pathway connects the VTA to the nucleus accumbens. The nucleus accumbens is located in the ventral striatum and integrates information from cortical and limbic brain structures to mediate behaviors the reinforce reward. It is a major target for the dopaminergic projections from the VTA, a group of neurons located close to the midline on the floor of the midbrain. The VTA is the origin of dopaminergic cell bodies that comprise the mesocorticolimbic dopamine system.BSR has been shown to result in the release of dopamine within the nucleus accumbens, which also occurs in response to natural rewards such as food or sex. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Electrophysiological data suggest stimulation of the MFB or VTA does not directly activate dopaminergic neurons in the mesolimbic reward pathway. These data suggest BSR is facilitated by initial excitation of descending, myelinated neurons, which then activate the ascending, unmyelinated neurons of the VTA. Excitatory, cholinergic inputs to the VTA are thought to play a role in this indirect activation, but the neuroanatomical components of this circuit have yet to be fully characterized. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Since the initial demonstration of BSR by Olds and Milner, experiments in rodents record ICSS responding to quantify motivation to receive stimulation. Subjects undergo stereotaxic surgery to permanently implant either a monopolar or bipolar electrode to the desired brain region. Electrodes are connected to a stimulating apparatus at the time of the experiment. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The first portion of an ICSS experiment involves training subjects to respond for stimulation using a fixed-ratio 1 (FR-1) reinforcement schedule (1 response = 1 reward). In experiments involving rats, subjects are trained to press a lever for stimulation, and the rate of lever-pressing is typically the dependent variable. In ICSS studies using mice, a response wheel is usually used instead of a lever, as mice do not consistently perform lever-pressing behaviors. Each quarter turn of the response wheel is recorded and rewarded with stimulation. The rewarding stimulus in BSR experiments is typically a train of short-duration pulses separated by interval pulses, which can be manipulated experimentally using the independent variables of stimulation amplitude, frequency, and pulse duration. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The amplitude (current) of stimulation determines the population of neurons being activated by the implanted electrode. In certain approaches, this is adjusted for every subject due to minor variability in electrode placement, and therefore a slightly different population of affected neurons. Following FR1 training, it is typical to establish a minimum, threshold current that produces sufficient levels of ICSS responding (about 40 responses per minute). This is called a discrete-trial current intensity procedure. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Each discrete trial consists of non-contingent stimulation at a certain amplitude followed by a brief window during which the animal can respond for more stimulation. Effective currents for BSR elicit responding above a certain rate (3 out of 4 trials, for example). The lowest current the animal responds sufficiently to is deemed the minimum effective current. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
This is done at a constant frequency, typically at the higher end of the frequency range employed in ICSS studies (140–160 Hz).Within-subject study design is often implemented to help eliminate variability introduced by electrode placement. Between-subject study design requires rigorous histologic verification of electrode placement to ensure consistency between experimental groups. Subjects with imperfect electrode placement require a higher simulation amplitude to activate the reward circuitry and produce ICSS responding. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Subjects with ideal anatomical placement will respond at lower stimulation amplitudes. This corrective process is limited, however, since increasing the population of activated neurons can result in off-target activation of neighboring circuitry. This is often culminated in undesired motor side effects upon stimulation, due to the adjacency of the MFB to the internal capsule, a bundle of axons carrying descending motor information to the brainstem. Inadvertent stimulation of these axons can lead to motor output such as movement of the head or paw twitching. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
At a constant minimum effective current, ICSS responding is recorded over a series of trials, which vary in stimulation frequency. Each trial consists of a short priming phase of non-contingent stimulation, a response phase where responses are recorded and rewarded with stimulation, and a short time-out phase where responses are not recorded and no stimulation is delivered. This is repeated for a series of 10-15 different ascending or descending frequencies, in 0.05 log-unit increments, which range anywhere from 20 to 200 Hz.While the amplitude of the stimulation influences which neurons are stimulated, the frequency of stimulation determines the firing rate induced in that neuronal population. Generally, increasing stimulation frequency increases the firing rate in the target population. This is associated with higher ICSS response rates, eventually reaching a maximum level at the maximum firing rate, limited by the refractory properties of neurons. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The independent variables of stimulation train and pulse duration can also be varied to determine how each affects ICSS response rates. Longer train durations produce more vigorous responding up to a point, after which rate of responding varies inversely with train length. This is due to lever-pressing for additional stimulation before the previously earned train has finished.The reinforcement schedule can also be manipulated to determine how motivated an animal is to receive stimulation, reflected by how hard they are willing to work to earn it. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
This can be done by increasing the number of responses required to receive a reward (FR-2, FR-3, FR-4, etc.) or by implementing a progressive-ratio schedule, where the number of required responses continually increases. The number of required responses increases for each trial until the animal fails to reach the required number of responses. This is considered the "break-point" and is a good indication of motivation related to reward magnitude. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Stimulation intensity, pulse duration, or pulse frequency can be varied to determine dose-response functions ICSS responding using curve-shift analysis. This approach generally resembles traditional pharmacological dose-response curve where the frequency of stimulation, rather than the dose of a drug, is examined. This method allows for quantitative analysis of reward-modulating treatments on response rates in comparison to baseline conditions. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Lower stimulation frequencies fail to sustain ICSS responding at a probability above chance. Response rates increase rapidly over a dynamic range of stimulation frequencies as the frequency increases, until a maximum response rate is reached. Changes in the rate of response over this range reflects changes in the magnitude of the reward. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Rate-frequency, rate-intensity, or rate-duration functions make inferences about the potency and efficacy of stimulation, as well as elucidate how drugs alter the rewarding impact of stimulation.Curve-shift analysis is often used in pharmacological studies to compare baseline response rates to those following drug administration. The maximum response rate during baseline conditions is typically used to normalize data in a frequency-rate curve to a maximum control rate (MCR). More specifically, the number of responses for any given trial is divided by the highest number of responses recorded in a baseline condition trial, which is then multiplied by 100. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
In an experimental condition, if the MCR falls below 100% at the highest stimulation frequencies, it is thought to reflect an impacted capability or motivation to respond, potentially induced by a drug with sedative or aversive properties. Shifts above 100% of the MCR indicate improved ability or motivation to respond, potentially induced by a drug with rewarding or stimulant properties.Sensitivity of the neural circuitry to the rewarding properties of stimulation is assessed by analyzing left- or right-shifts in the M50, or the frequency at which 50% of the maximum number of responses was recorded. Reaching 50% of the MCR at a lower frequency is characteristic of a left-shift in the frequency-rate curve and sensitization of the reward circuitry to stimulation. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
An increase in the M50 indicates that a greater stimulation frequency was required to reach 50% of the MCR, and the reward circuitry has been desensitized by the experimental manipulation. Another way of analyzing the frequency-rate curve between control and experimental conditions is to do a linear regression through the ascending data points in a plot of raw data (which has not been normalized to the MCR). The point where y=0, or the x-intercept, is called the threshold frequency or theta zero (θ0). This is the frequency at which ICSS response rates are equal to 0 (and any frequency above this will theoretically elicit ICSS responding). | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Several major drug classes have been studied extensively in relation to ICSS behavior: monoaminergic drugs, opioids, cholinergic drugs, GABAergic drugs, as well as a small number of drugs from other classes. These studies generally compare ICSS responding at baseline and following drug administration. Typically, the frequency-rate approach is used to determine changes in the M50 or θ0.Drugs with increased addiction liability generally decrease the stimulation threshold for ICSS responding, while drugs with aversive properties generally increase the stimulation threshold to achieve ICSS responding. These studies provide insight into the specific neurochemical mechanisms involved in the facilitation of BSR, and how reward perception can be modulated by pharmacologically altering the activity of specific neurotransmitter systems. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Pharmacological manipulation of these systems can have either a direct or indirect effect on the activity of the reward circuitry. Understanding drug-specific effects on ICSS response thresholds has helped elucidate how different neurotransmitter systems influence the reward circuitry by either potentiating or suppressing sensitivity to rewarding stimulation and influencing motivation to perform reward-associated behaviors. BSR and drugs of addiction produce their rewarding effects through shared neuroanatomical and neurochemical mechanisms. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Studies using lesion, pharmacological, and anatomical mapping of the brain have revealed that many drugs of abuse (e.g. amphetamine, cocaine, opioids, nicotine, etc.) activate the reward circuitry of the MFB, which is similarly activated by stimulation to achieve BSR. The neuronal axons of the mesolimbic dopamine system, a key component of the reward circuitry, generally have high thresholds for stimulation. However, these thresholds can be increased or decreased by drug administration, influencing sensitivity to intracranial stimulation and ICSS behavior. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
The effects of drugs that alter neurotransmission of dopamine, norepinephrine, and serotonin have been studied extensively in relation to BSR. Neurochemical studies have shown that BSR results in the release of dopamine within the nucleus accumbens. This effect is generally potentiated following administration of drugs that themselves increase the amount of extracellular dopamine in the nucleus accumbens, such as cocaine, which inhibits re-uptake of dopamine to the intracellular space by blocking its transporter. Conversely, these levels are decreased and the rewarding properties of BSR are blocked following administration of drugs that antagonize dopamine receptors or reduce the amount of extracellular dopamine, by promoting either degradation or re-uptake of the neurotransmitter. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
While dopamine is generally considered to be the main neurotransmitter implicated in the reward system, it is often not the only neurotransmitter affected by addictive, monoaminergic drugs. Importantly, the circuitry involved in BSR is multi-synaptic and not exclusively dopaminergic. This introduces potential for modulation by other neurotransmitter systems at different stages in the transmission of the reward signal. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Additionally, drugs that affect monoamine transmission vary in their selectivity. For example, drugs with high selectivity for increasing dopamine and norepinephrine transmission relative to serotonin transmission tend to have highly addictive properties. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Amphetamine and cocaine share this selectivity profile, and administration of these drugs generally results in a left-shift in M50 and θ0, indicating sensitization of the reward circuitry and high abuse potential. This characteristic leftward-shift of M50 in response to a moderate dose of cocaine is illustrated in a hypothetical data set in Figure 1. Note that the maximum response rate is reached at a lower frequency than it is at baseline, and there is a significant response rate at the lowest frequency, which did not produce responding under baseline conditions. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Even following chronic administration of methamphetamine or cocaine, there is little to no tolerance to ICSS facilitation. After chronic treatment is stopped, however, there is a withdrawal-induced depression of ICSS responding, which can be reversed by re-administering the drug.Drugs with more balanced selectivity for dopamine/norepinephrine and serotonin transmission, such as 3,4-methylenedioxy-methamphetamine (MDMA), tend to be less addictive, and they have mixed effects on ICSS responding depending on dose and stimulation frequency. Serotonin selective drugs, however, tend to result in either a lack of ICSS potentiation or depression of ICSS responding (a right-shift in frequency-rate curve), and these drugs are generally considered to be less addictive. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
One such example is fenfluramine, which was previously marketed as an appetite suppressant. Dopamine antagonists generally result in the depression of ICSS responding and a rightward-shift in the frequency-rate curve. This suggests decreased BSR and possibly increased aversive properties of the stimulation. Following chronic treatment with a dopamine antagonist, there is withdrawal-induced facilitation of ICSS, the opposite effect of what is observed following chronic treatment with stimulants. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Drugs that act on the opioid system generally vary in selectivity for the mu (μ), delta (δ), and kappa (κ) opioid receptors. Their addictive properties are highly dependent on these selectivities. Generally speaking, high potency mu-opioid receptor (MOR) agonists have high abuse potential, while kappa-opioid receptor (KOR) agonists generally produce a dysphoric state. Morphine, a MOR agonist, was one of the earliest studied drugs at the advent of ICSS and BSR. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
High potency MOR agonists like morphine have a somewhat varied effect on ICSS responding despite having high abuse potential, resulting in both potentiation and depression. The effect these drugs have on ICSS responding has been found to be highly dependent on dose, pretreatment time, and previous opioid exposure. Various studies on the effect of MOR-selective drugs including morphine, heroin, fentanyl, methadone, and hydrocodone have found mixed effects on ICSS responding. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Low doses of these drugs have been found to elicit weak facilitation of ICSS, while high doses result in a biphasic ICSS profile, consisting of a higher threshold for ICSS at lower frequencies followed by ICSS potentiation at higher frequencies. Upon chronic administration of high-potency MOR agonists at low doses, there is no tolerance to ICSS facilitation.Opioid receptor antagonists, such as naloxone, can reverse the effects of both opioid receptor agonists on ICSS responding and the potentiating effects of psychostimulants like methamphetamine. Naloxone, which is a competitive antagonist of all opioid receptor sub-types, does not influence ICSS responding when administered on its own. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
KOR agonism, typically associated with dysphoric states, more consistently results in a depression of ICSS responding. The KOR agonist salvinorin-A, for example, causes an overall decrease in ICSS response rates at lower stimulation frequencies. Repeated administration does not produce tolerance to ICSS depression. The effects of delta opioid receptor (DOR) agonists/antagonists on ICSS are less clear. One DOR agonist, SNC80, has been found to cause ICSS depression, but there is counter-evidence suggesting some delta agonists might have weak ICSS facilitation properties. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Cholinergic drugs have been less extensively studied than monoamines and opioids. The most commonly studied cholinergic drug is nicotine, the highly-addictive, psychoactive substance in cigarettes. Nicotine is an agonist of nicotinic acetylcholine receptors (nAchRs), which are ligand-gated ion channels. The addictive properties of nicotine have been found to be associated with agonism specifically of the α4β2 sub-type of nicotinic receptors. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Many studies have confirmed that low doses of nicotine result in ICSS facilitation, while higher doses result in ICSS depression. Chronic treatment with nicotine does not result in tolerance to ICSS facilitation at low doses, but does result in tolerance to the depressive effects of high doses. Withdrawal-induced depression of ICSS facilitation at low doses is also observed, as in MOR agonists and monoamine stimulants. The effects of nicotine treatment on ICSS response thresholds and maximum response rates are not as significant as they are in the case of many addictive MOR agonists and monoamine stimulants. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
GABAergic transmission is inhibitory, and the two main receptors for GABA are GABAA and GABAB. Drugs that act on GABAA receptors, which are ligand-gated ion channels, are more widely studied, as they generally produce more robust effects on sedation and anxiety, and they are commonly prescribed for therapeutic uses. Several of these drugs have addictive properties, including several benzodiazepines and barbiturates. Low doses of these drugs generally result in ICSS facilitation, while higher doses can result in depression of ICSS and an overall decrease in the maximum response rate. The latter is likely related to an impaired ability to respond due to the sedative and hypnotic properties of these drugs. Ethanol influences GABA receptor activity, and has been found to moderately facilitate ICSS, despite older publications suggesting these findings are inconsistent.GABAB receptor agonists and positive allosteric modulators have been found to result in ICSS depression and have been found to inhibit the reinforcing effects of several drugs, including cocaine, methamphetamine, and nicotine, reversing the ICSS facilitation these drugs typically cause. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Mechanisms of BSR offer a tool that provides insight into the way the brain governs behavior through motivation and reinforcement, especially in regard to addictive and compulsive behaviors. ICSS studies of BSR have proven to be a robust measure of reward sensitivity, and have potential to help assess the abuse liability of various future therapeutics. Additionally, ICSS studies have potential to be used to gauge how reward sensitivity is affected by genetic factors associated with addictive disorders. Drugs found to prevent ICSS facilitation have potential to be developed and therapeutically implemented to reduce the risk of addictive disorders in a clinical setting. | https://en.wikipedia.org/wiki/Brain_stimulation_reward |
Ciclovía (, Spanish: ), also ciclovia or cyclovia, is a Spanish term that means "cycleway", either a permanent bike path or the temporary closing of certain streets to automobiles for cyclists and pedestrians, a practice sometimes called open streets. | https://en.wikipedia.org/wiki/Ciclovía |
The inspiration for Ciclovías is credited to Bogotá, Colombia. In 1970 the National Capital Commission in Canada's capital Ottawa organized open streets for active transportation. The events have taken place since December 1974 when they started through the efforts of organizer Jaime Ortiz Mariño and others cyclist aficionados. In 1976 Bogota's Mayor Luis Prieto Ocampo signed the 566 and 567 decrees and Ciclovía became an official program promoted by the City government and supported by the Transportation Department. | https://en.wikipedia.org/wiki/Ciclovía |
In Bogotá, permanently designated bikeways are also known as ciclorrutas, while streets temporarily closed for that purpose are called ciclovías. Each Sunday and public holiday from 7 am until 2 pm certain main streets of Bogotá, Cali, Medellín, and other cities are temporarily blocked off to cars allowing runners, skaters, and bicyclists to workout in a more comfortable environment. At the same time, stages are set up in city parks. | https://en.wikipedia.org/wiki/Ciclovía |
Aerobics instructors, yoga teachers and musicians lead people through various performances. The great variety of traditional food and drinks offered in snack stalls motivates many locals and tourists to go around the Ciclovía. | https://en.wikipedia.org/wiki/Ciclovía |
Bogotá's weekly ciclovías are used by approximately 2 million people (about 20% of the population) on over 120 km of car-free streets.In 2007, a Colombian Congressman, José Fernando Castro Caycedo, proposed a law banning Ciclovia, charging that it caused traffic jams. Ciclovia users protested the change, and received support from ex-mayors Peñalosa and Samuel Moreno, as well as several members of the city council and other Members of Congress. The proposal was defeated. | https://en.wikipedia.org/wiki/Ciclovía |
The Bogota Ciclovía provides service from 7:00 am to 2:00 pm Sundays and holidays of the year by the main roads of the city, connected in a circuit of over 121 kilometers long and covers all sectors of the city. This time space was born in 1974. Since 1995 its management was taken over by the IDRD. Since then and gradually, it has been constructed to reach its present appearance and acceptance among its thousands of users. | https://en.wikipedia.org/wiki/Ciclovía |
Its infrastructure allows nearly one million (1,000,000) users leave their homes to safely practice different types of physical activities. The Ciclovía was awarded under the II International Competition 2005 Active Cities Healthy Cities, through its contribution to the development of an alternative and efficient physical activity in the city. Ciclovia routes 2016 | https://en.wikipedia.org/wiki/Ciclovía |
On the Gold Coast, Queensland, the City of Gold Coast held the city's first Ciclovia dubbed "Bike and Street Fest" on 4 May 2014. A section of Varsity Parade, Varsity Lakes was car-free for a four-hour celebration of bikes and all forms of active travel. The event included food stalls, street performers, live music and a BMX stunt show and attracted approximately 5000 visitors. Bike and Street Fest was held for a second consecutive year on Varsity Parade, Varsity Lakes on 3 May 2015. | https://en.wikipedia.org/wiki/Ciclovía |
The event again included street performers, live music and a BMX stunt show and ran in conjunction with the "Ride. Run. Walk." | https://en.wikipedia.org/wiki/Ciclovía |
event which hosted a number of fun runs and competitive bike rides. The event attracted an estimated 7,500 visitors.In Melbourne, the Merri-bek city council has held two Cyclovia events, on 28 May 2006 and 13 April 2008. A 4-kilometre (2.5 mi) section of the busy arterial Sydney Road was car-free for six hours. Bicycles and pedestrians filled the road, and trams also flowed as normal. A smaller (1.5 km long) section of same road is closed off to trams as well as motorised vehicles for the Sydney Road Street Party in the late southern summer each year. | https://en.wikipedia.org/wiki/Ciclovía |
Rosario was the first city in Argentina to hold an official Ciclovia, called Calle Recreativa. Each Sunday and holiday few important avenues of Rosario, are blocked off for the event to become carfree. From 8 am to 1 pm, runners, skaters and bicyclists take over the streets. Rosario's weekly ciclovías are used by approximately 30.000 people on over 13 km of carfree streets.Buenos Aires started its Ciclovías network in 2009, and as of 2013 it covers more than 100 km and continues expanding. | https://en.wikipedia.org/wiki/Ciclovía |
Brussels hosted its first Cyclovia on August 21, 2011. About 10 km of roads were totally or partially closed, with a course spanning from the Cinquantenaire Park throughout the centre of the city ending at the western boundary of the Small ring (Brussels). Another event is planned for September 11, 2011.The second Belgian Cyclovia will take place on the June 17, 2012. | https://en.wikipedia.org/wiki/Ciclovía |
Walkable city streets are commonly closed on Sunday in major cities, one notable example being Avenida Atlântica in Copacabana, Rio de Janeiro. São Paulo opens 118 km of car lanes to bikes-only every Sunday and holiday from 7 am to 4 pm, one of the most extensive programs in the world. The capital city of Brasilia also has a Sunday program with 16 km of lanes opened, complementing an extensive network of protected permanent bike lanes. Numerous other Brazilian cities have smaller programs. | https://en.wikipedia.org/wiki/Ciclovía |
Halifax held an event called Switch Open Streets on September 9, 2012 and planned to hold three more in 2013, beginning June 9, 2013. The first Switch attracted approximately 35,000 people and the event aims to create community ownership so that it may take place on more Sundays every year. In March 2012, Gil Penalosa visited Halifax. Winnipeg was the first city in Canada to hold an official Ciclovia, on Sunday, September 13, 2009. | https://en.wikipedia.org/wiki/Ciclovía |
The event saw thousands of people crowd Broadway on bikes, skateboards and on foot. The event was such a success that organizers, the Downtown Winnipeg BIZ, hope to make it an annual event.Vancouver held its first Ciclovias, called Vancouver LiveStreets, on June 26, 2011 and September 11, 2011. The events are a partnership between The City of Vancouver and the Vancouver Area Cycling Coalition (VACC).Calgary, Alberta has hosted the Bow River Flow since 2009. | https://en.wikipedia.org/wiki/Ciclovía |
Most recently, on August 21, 2011, it saw the opening of two lanes of the Memorial Drive Parkway for thousands of Calgarians to enjoy dozens of participatory activities in a non-consumeristic street festival Bow River Flow. Organizers have proposed larger scale multi-day events for 2012. | https://en.wikipedia.org/wiki/Ciclovía |
Hamilton is holding its seventh Open Streets event, based on the Ciclovia movement on June 23, 2013. The event is organized by a group of community partners and invites people to walk ride or roll down town through over 2K of James St. N car free. | https://en.wikipedia.org/wiki/Ciclovía |
Ottawa - Gatineau has been the site of Ciclovías-type street closures (for motorised vehicles) since 1970, organised by the National Capital Commission. Every Sunday morning from Victoria Day until Labour day over 50 kilometres of roads in the heart of Ottawa and nearby Gatineau Park are reserved for cyclists, in-line skaters, runners, and pedestrians. This initiative is called the Sunday Bikedays Program. | https://en.wikipedia.org/wiki/Ciclovía |
In 2021 the NCC converted Sunday Bike Days to Weekend Bike Days and added weekday closures on Queen Elizabeth Drive and Colonel By Drive to create more space for active transportation. Toronto Is relatively new to this initiative and started in 2014 with annual event of weekend closures for the two main streets: Yonge and Bloor. Closed part of streets reached 10 km in 2016 and had over 80 000 participants. Event is accompanied by multiple "activity hubs" - nodes of active programming spaced along the Open Streets TO route. This annual event is named the Open Streets TO. | https://en.wikipedia.org/wiki/Ciclovía |
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