A neuron can receive thousands of EPSPs from different neurons, and responds by triggering or not triggering an action potential. This addition and response to the net effect of postsynaptic potentials is called .

The addition and response to the net effect of postsynaptic potentials is called Spatial summation

Explanation:

Signal summation occurs when impulses received by a neuron are eummed together to reach the excitation threshold to fire a neuron. It occurs at the axon hillock of a neuron. Signal summation occurs since each neuron is connected to many other neurons, often receiving multiple impulses from them, both excitatory and inhibitory.

Signal summation can either be temporal or spatial.

Temporal summation, occurs when impulses received at the same place on the neuron in close temporal succession add up to initiate an action potential in the neuron.

Spatial summation occurs when impulses received simultaneously at different places on the neuron add up to initiate an action potential in the neuron.

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