organism/neuron/appunti/2026-03-30-behavior-POST.md

## BEH-POST-UNIFIED: The Integrated Postsynaptic Model

### **ms: behaviors (Fast Kinetics & Gate Logic)**

#### **Voltage-Context: Episode**

*Determines the total depolarization level (Vpost​) available to clear the NMDA Mg-block.*

- **Vpost_Maximum: Episode**
  - — `V_bAP` full OR (`g_AMPA` full AND `V_bAP` medium)
  - — Result: Vpost​ is high enough for complete Mg-block removal.
- **Vpost_Attenuated: Episode**
  - — `g_AMPA` medium AND `V_bAP` empty/low
  - — Result: Vpost​ is sub-threshold; Mg-block partially remains.
- **Vpost_Passive: Episode**
  - — `g_AMPA` empty AND `V_bAP` empty
  - — Result: Vpost​ at rest; Mg-block fully intact.

#### **NMDA-Coincidence: Context**

- **NMDA_Open: Episode**
  - — `NT_cleft` full AND `V_post` maximum
  - — Result: Capost​ surges; triggers high ATP demand for clearance.
- **NMDA_LogicBlocked: Episode**
  - — `NT_cleft` full BUT `V_post` attenuated/passive
  - — Result: Mg-block prevents Ca2+ influx despite NT presence.
- **NMDA_LigandBlocked: Episode**
  - — `V_post` maximum BUT `NT_cleft` empty
  - — Result: No glutamate to open the channel; Ca2+ entry zero.

#### **Ca-Dynamics & ATP-Drain: Context**

- **Clearance_Optimal: Episode**
  - — `ATP_level_post` full
  - — Result: Pumps flush Ca2+ rapidly; `ATP_demand_post` increases.
- **Clearance_Failing: Episode**
  - — `ATP_level_post` low/empty
  - — Result: Ca2+ remains elevated (residual floor); creates "False Trigger" conditions.

---

### **sec: behaviors (Signal Integration & Fate)**

#### **Synaptic-Weight-Decision (Plasticity)**

- **Plasticity_LTP: Episode**
  - — `Ca_post_history` (recent 2s) is **Full**
  - — Result: High-frequency/High-amplitude coincidence detected; tags synapse for AMPA increase.
- **Plasticity_LTD: Episode**
  - — `Ca_post_history` is **Medium**
  - — Result: Low-frequency or poorly timed coincidence; tags synapse for AMPA removal.

#### **Retrograde-Feedback (eCB)**

- **eCB_Synthesis_Active: Episode**
  - — `Ca_post_history` > threshold (0.7)
  - — **Logic A (Protection):** Response to genuine NMDA over-activity.
  - — **Logic B (Error):** Response to pump failure (Ca2+ accumulation due to low ATP).
- **eCB_Synthesis_Idle: Episode**
  - — `Ca_post_history` < threshold; eCB level decays.

---

### **min: behaviors (Bioenergetics & Structural Change)**

#### **Metabolic-Recovery**

- **Astrocyte_Supply_Active: Episode**
  - — `Glucose_level` full; `ATP_level_post` is replenished.
- **Astrocyte_Supply_Crises: Episode**
  - — `Glucose_level` low; `ATP_level_post` remains empty; Ca2+ pumps fail.

#### **Structural-Update**

- **AMPA_Population_Increase: Episode**
  - — Triggered by `Plasticity_LTP` AND `ATP_level_post` NOT empty.
  - — Result: `g_AMPA_baseline` shifts higher for next cycle.
- **AMPA_Population_Decrease: Episode**
  - — Triggered by `Plasticity_LTD`.
  - — Result: `g_AMPA_baseline` shifts lower.

---

### **Key Structural Observations**

1. **The Vpost Priority:** Vpost​ is now the "sum" of local input and global feedback. This allows the model to simulate both **Hebbian learning** (needs a bAP) and **Homeostatic Scaling** (where enough local AMPA activity can eventually trigger the NMDA gate alone).
2. **The ATP Bottleneck for LTP:** Note that in the `min` behaviors, I’ve added a constraint: LTP requires `ATP_level_post` to be healthy. Moving receptors into the membrane is a physical "work" process. If the synapse is energy-starved, it might "decide" to do LTP in the `sec` loop but fail to **execute** it in the `min` loop.
3. **The Coincidence Hierarchy:**
   - **LTP** = Perfect Timing (NT + bAP).
   - **LTD** = Misaligned Timing (Low NT or Out-of-sync bAP).
   - **False eCB** = Metabolic Failure (No NT, No bAP, just Low ATP).