Temporal summation is a response to the:
amount of neurotransmitter released from a presynaptic cell.
frequency of stimulation of a postsynaptic cell.
density of ligand-gated channels on the postsynaptic cell.
location of synapses over the surface of a postsynaptic neuron.

Temporal summation is a response to the frequency of stimulation of a postsynaptic cell.

Explanation:

Summation is understood to mean the calculation of nerve impulses arriving in the nerve cell, which can either have an excitatory or an inhibitory effect on the development of an action potential. It can be either spatial or temporal.

In temporal summation, if several excitatory or inhibitory potentials occur in the neuron from a single synapse in sufficiently short time intervals, these are also summed up and if a certain threshold value is exceeded, an action potential arises at the axon hill.

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