🎨 Programming Framework Color Coding
Triggers: Neural activity, calcium signals, neurotransmitter release
Enzymes: Kinases, phosphatases, proteases, calcium-binding proteins
Intermediates: Calcium ions, second messengers, signaling complexes
Processing: Phosphorylation, protein synthesis, receptor trafficking
Products: Synaptic strength changes, structural modifications, memory formation
⚡ Long-Term Potentiation (LTP)
Synaptic strengthening mechanisms for memory formation
1. NMDA Receptor-Dependent LTP
The primary mechanism for synaptic strengthening in excitatory synapses, involving calcium influx through NMDA receptors and subsequent activation of calcium-dependent signaling cascades.
graph TD
A[High Frequency Stimulation] --> B[Glutamate Release]
B --> C[AMPA Receptor Activation]
C --> D[Postsynaptic Depolarization]
D --> E[Mg2+ Block Relief]
E --> F[NMDA Receptor Opening]
F --> G[Calcium Influx]
G --> H[Calcium-Calmodulin Complex]
H --> I[CaMKII Activation]
I --> J[CaMKII Autophosphorylation]
J --> K[AMPA Receptor Phosphorylation]
K --> L[AMPA Receptor Trafficking]
L --> M[Synaptic Strength Increase]
N[Calcium Signal] --> O[Calcineurin Activation]
O --> P[PP1 Activation]
P --> Q[Inhibitor-1 Phosphorylation]
Q --> R[PP1 Inhibition]
R --> S[CaMKII Persistence]
S --> T[LTP Maintenance]
style A fill:#ff6b6b,color:#fff
style B fill:#51cf66,color:#fff
style C fill:#74c0fc,color:#fff
style D fill:#74c0fc,color:#fff
style E fill:#51cf66,color:#fff
style F fill:#74c0fc,color:#fff
style G fill:#ff6b6b,color:#fff
style H fill:#74c0fc,color:#fff
style I fill:#ffd43b,color:#000
style J fill:#51cf66,color:#fff
style K fill:#51cf66,color:#fff
style L fill:#51cf66,color:#fff
style M fill:#b197fc,color:#fff
style N fill:#ff6b6b,color:#fff
style O fill:#ffd43b,color:#000
style P fill:#ffd43b,color:#000
style Q fill:#51cf66,color:#fff
style R fill:#51cf66,color:#fff
style S fill:#51cf66,color:#fff
style T fill:#b197fc,color:#fff
Triggers & Conditions
Catalysts & Enzymes
Chemical Processing
Intermediates
Products
📉 Long-Term Depression (LTD)
Synaptic weakening mechanisms for memory refinement
2. NMDA Receptor-Dependent LTD
Synaptic weakening mechanism that occurs with low-frequency stimulation, involving calcium-dependent activation of phosphatases and removal of AMPA receptors from the synapse.
graph TD
A[Low Frequency Stimulation] --> B[Glutamate Release]
B --> C[AMPA Receptor Activation]
C --> D[Weak Postsynaptic Depolarization]
D --> E[Partial Mg2+ Block Relief]
E --> F[Limited NMDA Opening]
F --> G[Moderate Calcium Influx]
G --> H[Calcium-Calmodulin Complex]
H --> I[Calcineurin Activation]
I --> J[PP1 Activation]
J --> K[AMPA Receptor Dephosphorylation]
K --> L[AMPA Receptor Endocytosis]
L --> M[Synaptic Strength Decrease]
N[Calcium Signal] --> O[Calcium-Calmodulin]
O --> P[Calcineurin Complex]
P --> Q[PP1 Recruitment]
Q --> R[AMPA Receptor Removal]
R --> S[Synaptic Depression]
style A fill:#ff6b6b,color:#fff
style B fill:#51cf66,color:#fff
style C fill:#74c0fc,color:#fff
style D fill:#74c0fc,color:#fff
style E fill:#51cf66,color:#fff
style F fill:#74c0fc,color:#fff
style G fill:#ff6b6b,color:#fff
style H fill:#74c0fc,color:#fff
style I fill:#ffd43b,color:#000
style J fill:#ffd43b,color:#000
style K fill:#51cf66,color:#fff
style L fill:#51cf66,color:#fff
style M fill:#b197fc,color:#fff
style N fill:#ff6b6b,color:#fff
style O fill:#74c0fc,color:#fff
style P fill:#74c0fc,color:#fff
style Q fill:#51cf66,color:#fff
style R fill:#51cf66,color:#fff
style S fill:#b197fc,color:#fff
Triggers & Conditions
Catalysts & Enzymes
Chemical Processing
Intermediates
Products
⚖️ Synaptic Scaling
Homeostatic regulation of synaptic strength
3. Activity-Dependent Synaptic Scaling
Homeostatic mechanism that globally adjusts synaptic strength in response to changes in neuronal activity, maintaining network stability and preventing runaway excitation or depression.
graph TD
A[Chronic Activity Changes] --> B[Calcium Signal Integration]
B --> C[Activity Sensor Activation]
C --> D[Transcription Factor Activation]
D --> E[Gene Expression Changes]
E --> F[Protein Synthesis]
F --> G[AMPA Receptor Subunit Changes]
G --> H[Synaptic Strength Adjustment]
I[Low Activity] --> J[Calcium Decrease]
J --> K[CREB Activation]
K --> L[BDNF Expression]
L --> M[AMPA Receptor Insertion]
M --> N[Synaptic Strengthening]
O[High Activity] --> P[Calcium Increase]
P --> Q[TNF-α Expression]
Q --> R[AMPA Receptor Removal]
R --> S[Synaptic Weakening]
style A fill:#ff6b6b,color:#fff
style B fill:#74c0fc,color:#fff
style C fill:#ffd43b,color:#000
style D fill:#ffd43b,color:#000
style E fill:#51cf66,color:#fff
style F fill:#51cf66,color:#fff
style G fill:#51cf66,color:#fff
style H fill:#b197fc,color:#fff
style I fill:#ff6b6b,color:#fff
style J fill:#74c0fc,color:#fff
style K fill:#ffd43b,color:#000
style L fill:#51cf66,color:#fff
style M fill:#51cf66,color:#fff
style N fill:#b197fc,color:#fff
style O fill:#ff6b6b,color:#fff
style P fill:#74c0fc,color:#fff
style Q fill:#51cf66,color:#fff
style R fill:#51cf66,color:#fff
style S fill:#b197fc,color:#fff
Triggers & Conditions
Catalysts & Enzymes
Chemical Processing
Intermediates
Products
🏗️ Structural Plasticity
Morphological changes in synaptic structure
4. Dendritic Spine Remodeling
Long-term structural changes in dendritic spines that underlie persistent synaptic modifications, involving actin cytoskeleton reorganization and protein synthesis.
graph TD
A[Synaptic Activity] --> B[Calcium Signal]
B --> C[Rho GTPase Activation]
C --> D[Actin Polymerization]
D --> E[Spine Head Enlargement]
E --> F[PSD Expansion]
F --> G[Structural LTP]
H[Activity Pattern] --> I[Calcium Dynamics]
I --> J[Protease Activation]
J --> K[Actin Depolymerization]
K --> L[Spine Retraction]
L --> M[Synapse Elimination]
N[BDNF Signaling] --> O[TrkB Activation]
O --> P[PI3K Activation]
P --> Q[Protein Synthesis]
Q --> R[Spine Growth]
R --> S[New Synapse Formation]
style A fill:#ff6b6b,color:#fff
style B fill:#74c0fc,color:#fff
style C fill:#ffd43b,color:#000
style D fill:#51cf66,color:#fff
style E fill:#51cf66,color:#fff
style F fill:#51cf66,color:#fff
style G fill:#b197fc,color:#fff
style H fill:#ff6b6b,color:#fff
style I fill:#74c0fc,color:#fff
style J fill:#ffd43b,color:#000
style K fill:#51cf66,color:#fff
style L fill:#51cf66,color:#fff
style M fill:#b197fc,color:#fff
style N fill:#ff6b6b,color:#fff
style O fill:#ffd43b,color:#000
style P fill:#ffd43b,color:#000
style Q fill:#51cf66,color:#fff
style R fill:#51cf66,color:#fff
style S fill:#b197fc,color:#fff
Triggers & Conditions
Catalysts & Enzymes
Chemical Processing
Intermediates
Products