Il DEV contiene quei behavior di modulazione che cambiano la somma (fullness + active). La modulazione DEV aumenta/diminuisce (fullness + active). Ovvero c’e’ creazione di nuova “forma” di possibilita’.
This is critical for long-term presynaptic changes. The postsynaptic cell, upon detecting specific activity patterns (like those for LTP/LTD), releases chemical signals that travel backwards to the presynaptic terminal, instructing it to change.
- Nitric Oxide (NO): A gas that diffuses freely. During postsynaptic LTP induction (strong NMDAR activation), neuronal NO synthase (nNOS) is activated. NO diffuses into the presynaptic terminal and activates soluble guanylyl cyclase (sGC), raising cGMP levels. This enhances vesicle release via PKG, contributing to presynaptic LTP.
- Endocannabinoid-Mediated LTP (eLTP): In some synapses, a postsynaptic depolarization triggers production of endocannabinoids (e.g., 2-AG). These bind to presynaptic CB1 receptors, but surprisingly, can initiate a signaling cascade (involving cAMP/PKA) that increases Pr for a long period.
- Neurotrophins (BDNF): Released from the postsynapse in an activity-dependent manner. Presynaptic TrkB receptors activate pathways (PI3K, MAPK) that enhance vesicle docking and Pr.
- Classical Endocannabinoid-Mediated LTD (eCB-LTD): More common. Moderate postsynaptic activity (mGluR activation or moderate Ca²⁺ rise) triggers 2-AG release. 2-AG binds presynaptic CB1 receptors, which inhibit VGCCs and directly inhibit the release machinery via Gi/o protein signaling, reducing Pr for a long time.
- Other Lipid Mediators (like LPA) can also act as retrograde signals for depression.
Augmentation:
- Calcium-sensing proteins (Munc13) alter release probability (1-10s range). How?
Qui la PRE e la POST si predispongono per dare le condizioni a SYN di stabilire o eliminare una sinapsi. Per ora questo comportamento lo mettiamo in TUN perche’ non si tratta di creare o distruggere PRE o POST, ma di rendere disponibile a SYN la possibilita’ di creare o distruggere una SYN. Durante il Day c’e’ il TUN che mette a disposizione, durante il Night SYN crea o distrugge gli accoppiamenti PRE POST.
ATTENZIONE: Questo e POST e’ da cambiare, perche’ c’e’ il passaggio da TubPoss a TubPossSyn a TubAct. E’ la SYN che passa in TubAct.
> Minutes/hours Time Scale
```Gen
modulator: DEV-TUB-CONCEPTUAL
contained_by: DEV-N
```
### DEV-AXO-BEH-PRE-TUB: Modulator
Qui stiamo ragionanando sulla trasformazione fra bottone presinaptico inattivo e bottone attivo, pronto a diventare parte di una sinapsi. Il ragionamento e' locale, e mette a disposizione o toglie un bottone attivo che un altro ragionamento, credo in TUN-WTA, fara' su questo bottone, il bottone postisinaptico e una sinapsi disponibile.
```Gen
modulator: DEV-AXO-BEH-PRE-TUB
contained_by: DEV-TUB-CONCEPTUAL
modulates: BEH-AXO/expansion/BEH-PRE
# qui stiamo modulando fullness e actual del tub BEH-PRE associandoli
# a tub_modulation prePos e PreAct.
tub_modulation: # in TUN agiamo su fullness <-> active
- fulMod ( fullness: None, active: BEH-PRE/fullness, empty: 0x ) # riferimento a possible di BEH-PRE
- actMod ( fullness: None, active: BEH-PRE/active, empty: BEH-PRE/emptiness ) # riferimento a active di BEH-PRE