Question

How does temporal summation create an action potential? ______

A) Potentials are generated on several dendrites at the same time to trigger threshold and the production of an action potential.
B) The temporal lobe in the brain stimulates EPSPs to trigger an action potential.
C) Generator potentials are at the same tempo on adjacent neurons.
D) It is frequency modulated and of the same amplitude for intensity.
E) Two or more postsynaptic potentials are generated in rapid succession at the same synapse before they can dissipate, thereby exceeding threshold.

Answer 1

Temporal summation leads to an action potential by rapidly producing multiple postsynaptic potentials at the same synapse, which accumulate to exceed the threshold for firing an action potential, primarily occurring at the axon hillock.

Step-by-step explanation:

Temporal summation creates an action potential when two or more postsynaptic potentials are generated in rapid succession at the same synapse before they can dissipate.

This cumulative effect exceeds the neuronal threshold, leading to the firing of an action potential.

The axon hillock, with its high density of voltage-gated Na+ channels, plays a crucial role here, as it is where the summation and initial phase of the action potential occur. Unlike spatial summation, which involves inputs from multiple dendrites, temporal summation involves repeated inputs at a single synapse within a short timeframe.

The process of temporal summation serves as a mechanism to ensure that only significant signals lead to an action potential, thus acting as a filter to prevent the relay of random 'noise' in the nervous system.