A Postsynaptic Neuron Has Three Presynaptic Inputs - from Neurons

Multiple Choice

A postsynaptic neuron has three presynaptic inputs - from neurons X, Y, and Z. When X and Y are stimulated simultaneously and repeatedly, the postsynaptic neuron reaches threshold and undergoes an action potential. When X and Z are stimulated simultaneously, however, there is no change in the membrane potential of the postsynaptic neuron. The simultaneous stimulation of X and Y is an example of

A) temporal summation.
B) presynaptic inhibition.
C) spatial summation.
D) neuronal divergence.
E) presynaptic facilitation.