Which of the following statements about neurons is true?
A) They fire action potentials only on the basis of the number of excitatory inputs they receive.
B) They sum excitatory and inhibitory postsynaptic potentials.
C) The "decision" to fire is made in the dendrites.
D) They make spatial, but not temporal, summations.
E) Both a and c

Question

Quizplus · Accepted Answer

Neurons sum both excitatory and inhibitory postsynaptic potentials (EPSPs and IPSPs) to determine whether or not to fire an action potential. This process of integrating incoming signals occurs in the cell body or soma, not the dendrites. Therefore, option C is incorrect. Option A is incorrect because the number of excitatory inputs alone does not determine if a neuron will fire, as the inhibitory inputs also play a role. Option D is incorrect because neurons can also make temporal summations, which occur when the EPSPs and IPSPs arrive close together in time.

Which of the Following Statements About Neurons Is True