E6 Synaptic integration (spatial and temporal summation)

Title

The neuron continuously integrates the excitatory and inhibitory synaptic inputs generated at E4 and E5, summing them both in time (temporal summation, when successive inputs overlap before decaying) and in space (spatial summation, when simultaneous inputs at different points of the dendrite converge on the soma). Passive attenuation of the signal along the dendrite reuses the lambda length constant defined in E03. When the net sum of current exceeds a threshold, an action potential is triggered, which is modeled in a simplified way with the integrate-and-fire scheme, where the voltage is reset after each trigger. Inhibition can act subtractively (hyperpolarizing) or in a divisive/shunting manner (reducing the gain of the neuron without changing the membrane potential much), a key mechanism for the control of network excitability described in E8.

ID:4264