# soma.md Qui comprendiamo: - SOMA: il soma - VGSC-SOMA-H: Na ion channels. Open only when VDB high - VGSC-SOMA-M: Na ion channels. Open only when VDB medium - VGSC-SOMA-L: Na ion channels. Open only when VDB low ## SOMA: container --- **Simplified verifiable behaviors**: — ms: - Resting at -70 mV: Leak channels + pumps (keep at resting) - VDB Depolarization : ~1-2 ms: Na⁺ enters (some VGSCs open) - Opened VGSC and then remain closed for a refractory period - Spike if depolarized above threshold: to -50 mV - Ca2+ enter - Repolarization to -70 mV: ~1-2 ms: K⁺ exits (VG K⁺ channels open) ← NOT pumps! - After-hyperpolarization: ~5-20 ms: K⁺ channels still open — secs: - Return to exact -70 mV: ~100-1000 ms: Na⁺/K⁺ pumps restore gradients - Ca2+ accumulation — mins: - VGSC modulation --- **G expression**: — ms: - based on VDB, VGSC open and let Na+ in. VGSG then go into refractory - if Na fullness then ApCtx. Here the threshold is based only on the integration of Na+ - increase SpikeTrainTraces (fast at spike) - increase Ca2+ traces - decrease Na: fast pump which decreases Na+, we do not model K+ -- there is a tug of war between Na entering and exiting. Na can reach fullness only if VDB increases fast (derivative) - there are 2 context: ApCtx and RefractorySoma imlemented with timers and tunable - decrease SpikeTraintraces slow, only if away from spiketrain this is empty - Tune: -- The threshold is tuned during the spiketrain. Low threshold at rest, to increase sensitivity, threshold increase during spike to increase discrimination — secs: - SpikeTrainTraces — mins: - Tune: -- refractory lenght --- **Tubs:** - **VDB**: dendrites deliver current - **Na**: are a proxy for the Coulombs of charge building up on the somatic membrane. They are used to check threshold, but also to mimic Na+ and K+ pumping - **Ca2+**: Medium term traces to guide tuning and Night development. It is a local trace, ATP is a global (Astrocyte) - **SpikeTrainTraces**: sono le tracce che consentono al neurone di far partire il Tuning neuronale, quando e' lontano da uno spike-train, ovvero e' in riposo. - **RefractorySoma**: tracce di refractory --- ```Gen container: SOMA expansion: - VGSC-SOMA-H ( fullness: 50x, active: 20x, emptiness: 10x ) # modulated_by: VGSC-SOMA-H-TUN # possible/actual - VGSC-SOMA-M ( fullness: 50x, active: 20x, emptiness: 10x ) # modulated_by: VGSC-SOMA-M-TUN # possible/actual - VGSC-SOMA-L ( fullness: 50x, active: 20x, emptiness: 10x ) # modulated_by: VGSC-SOMA-L-TUN # possible/actual tub_local: - VDB - Na - Ca2+ - RefractorySoma tub_intricated: - SpikeTrainTraces ( contained_in: DAY-N ) ``` ### ms: SOMA #### VDB-Concentration: check_tpc As dendrites deliver current (VDB​), the soma acts like a capacitor. It "stores" this charge in the form of membrane potential. This contextualizes VGSC-SOMA to open ion channels that let Na+ ions in. This only applies if not ApCtx, or in other words, SOMA is not in refractory period. ```Gen check_tpc: VDB-Concentration contained_by: SOMA tpc: any rf: ( active: 60x ) condition: (VDB fullness ) AND NOT ApCtx out_tpc: VDBMaxCtx condition: ( VDB mediumness ) AND NOT ApCtx out_tpc: VDBMediumCtx condition: ( VDB emptiness ) AND NOT ApCtx out_tpc: VDBLowCtx ``` #### SomaSpill: interacting ```Gen interacting: SomaSpill contained_by: SOMA context: any rf: ( active: 8x ) hypothesis: NOT NA emptiness action: [ decrease NA ] trace: ``` #### SomaSpike: check_tpc Qui siamo nella fase effettiva di spike, non refractory che viene dopo. Fa da contesto di durata fra un RF ed un altro. La fullness di Na rappresenta il threshold e puo' essere modificato. La fullness di RefractorySoma rappresenta la lunghezza del refractory. ```Gen check_tpc: SomaSpike contained_by: SOMA context: fixed rf: ( active: 60x ) condition: ( Na fullness ) AND ( RefractorySoma emptiness ) out_context: ApCtx out_context: bApCtx ``` #### ApBeh: interacting Durante la fase effettiva di spike, eliminiamo Na accumulati, riempiamo RefractorySoma per fase di refractory e riempiamo Ca2+ per le tracce medio termine di potenziamento/depotenziamento. ```Gen interacting: ApBeh contained_by: SOMA context: ApCtx rf: ( active: 8x ) hypothesis: NOT Na empty action: [ decrease Na ] trace: hypothesis: NOT RefractorySoma full action: [ increase RefractorySoma ] trace: hypothesis: NOT Ca2+ full action: [ increase Ca2+ ] trace: ``` #### RefractorySpill: interacting Lo spill deve essere piu' lento dell'increase che avviene in APBeh ```Gen interacting: RefractorySpill contained_by: SOMA context: any rf: ( active: 16x ) hypothesis: NOT RefractorySoma empty action: [ decrease RefractorySoma ] trace: ``` ### sec: SOMA ### min: SOMA #### VGSC-SOMA-TUN: Tuner ```Gen tuner: VGSC-SOMA-TUN contained_by: SOMA tunes: SOMA/expansion/VGSC-SOMA context_intricated: - TunPossible ( contained_by: DAY-N ) tub_local: tub_intricated: ``` ##### Check: check_tpc ```Gen context: check_tpc contained_by: VGSC-SOMA-TUN context: TunPossible rf: ( active: 60x ) condition: out_context: TunSomaVcgg ``` ##### ?: interacting ```Gen interacting: ? contained_by: TUN-PRE-VGCC context: TunSomaVcgg rf: ( active: x ) hypothesis: action: trace: ``` ## VGSC-SOMA-H: container Voltage Gated Sodium Channel: difficult to open (High) ```Gen container: VGSC-SOMA-H tub_local: Ready ( ) tub_intricated: Na ( contained_in: SOMA) ``` ### sec: VGSC-SOMA-H #### NaEnterH: interacting Se metto il controllo sulla (NOT Ready fullness) il VGSC puo' far entrare un numero di Na non superiore ad un massimo. ```Gen interacting: NaEnterH contained_by: VGSC-H-SOMA context: VDBMaxCtx AND ( NOT RefractoryH ) rf: ( active: 1x ) hypothesis: ( NOT Na fullness ) AND ( NOT ReadyH fullness ) action: [ Na increase, ReadyH increase ] trace: None ``` ##### CheckRefractoryH: check_tpc Il check su refractory deve essere fatto ad un RF maggiore della eliminazione di Refractory. Questo perche' e' un era nella qualle avviene l'episodio. ```Gen check_tpc: CheckRefractoryH contained_by: VGSC-H-SOMA context: NOT RefractoryH rf: ( active: 60x ) condition: ( ReadyH fullness ) out_context: RefractoryH ``` ##### RefractoryH: interacting Questo episodio deve girare varie volte nell'ambito del contesto di refractory che viene controllato ad un RF maggiore. ```Gen interacting: RefractoryH contained_by: VGSC-H-SOMA context: RefractoryH rf: ( active: 1x ) hypothesis: NOT ( ReadyH emptyness ) action: [ ReadyH decrease ] trace: None ``` ## VGSC-SOMA-M: container Voltage Gated Sodium Channel: less difficult to open (Medium) ```Gen container: VGSC-SOMA-M tub_local: Ready ( ) tub_intricated: Na ( contained_in: SOMA) ``` ### sec: VGSC-SOMA-M #### NaEnterM: interacting Se metto il controllo sulla (NOT Ready fullness) il VGSC puo' far entrare un numero di Na non superiore ad un massimo. ```Gen interacting: NaEnterM contained_by: VGSC-M-SOMA context: (VDBMediumCtx OR VDBMaxCtx) AND ( NOT RefractoryM ) rf: ( active: 1x ) hypothesis: ( NOT Na fullness ) AND ( NOT ReadyM fullness ) action: [ Na increase, ReadyM increase ] trace: None ``` ##### CheckRefractoryM: check_tpc Il check su refractory deve essere fatto ad un RF maggiore della eliminazione di Refractory. Questo perche' e' un era nella qualle avviene l'episodio. ```Gen check_tpc: CheckRefractoryM contained_by: VGSC-M-SOMA context: NOT RefractoryM rf: ( active: 60x ) condition: ( ReadyM fullness ) out_context: RefractoryM ``` ##### RefractoryM: interacting Questo episodio deve girare varie volte nell'ambito del contesto di refractory che viene controllato ad un RF maggiore. ```Gen interacting: RefractoryM contained_by: VGSC-M-SOMA context: RefractoryM rf: ( active: 1x ) hypothesis: NOT ( ReadyM emptyness ) action: [ ReadyM decrease ] trace: None ``` ## VGSC-SOMA-L: container Voltage Gated Sodium Channel: easy to open (Low) ```Gen container: VGSC-SOMA-L tub_local: Ready ( ) tub_intricated: Na ( contained_in: SOMA) ``` ### sec: VGSC-SOMA-L #### NaEnterL: interacting Se metto il controllo sulla (NOT Ready fullness) il VGSC puo' far entrare un numero di Na non superiore ad un massimo. ```Gen interacting: NaEnterL contained_by: VGSC-L-SOMA context: ( VDBLowCtx OR VDBMediumCtx OR VDBMaxCtx) AND ( NOT RefractoryL ) rf: ( active: 1x ) hypothesis: ( NOT Na fullness ) AND ( NOT ReadyL fullness ) action: [ Na increase, ReadyH increase ] trace: None ``` ##### CheckRefractoryL: check_tpc Il check su refractory deve essere fatto ad un RF maggiore della eliminazione di Refractory. Questo perche' e' un era nella qualle avviene l'episodio. ```Gen check_tpc: CheckRefractoryL contained_by: VGSC-L-SOMA context: NOT RefractoryL rf: ( active: 60x ) condition: ( ReadyL fullness ) out_context: RefractoryL ``` ##### RefractoryL: interacting Questo episodio deve girare varie volte nell'ambito del contesto di refractory che viene controllato ad un RF maggiore. ```Gen interacting: RefractoryL contained_by: VGSC-L-SOMA context: RefractoryL rf: ( active: 1x ) hypothesis: NOT ( ReadyL emptyness ) action: [ ReadyL decrease ] trace: None ```