SUMMATION is the process by which excitatory and inhibitory impulses are combined to determine whether or not a neuron fires.
In physiology, summation is the additive effect of numerous electrical impulses on a neuromuscular junction which is the junction between the nerve cell and muscle cell. The stimuli cannot evoke a response individually. But, collectively they can generate a response.
The summation of postsynaptic potentials, which are excitatory postsynaptic potentials (ESPs) and inhibitory postsynaptic potentials (IPSPs) by a postsynaptic neuron allows a neuron to integrate the electrical information received that is provided by all the inhibitory and excitatory synapses acting on it at any given moment. Whether the totality of active synaptic inputs results in the production of an action potential, this entirely depends on the balance between inhibition and excitation.
Summation has two types: temporal summation and spatial summation. The former is the successive stimulation on one nerve. The latter, on the other hand, is the addition of simultaneous stimuli from conducting fibers.
Therefore, the answer is B. SUMMATION.
