Question

If a neuron receives a series of stimuli whose effect is excitatory but subthreshold, the neuron is more excitable to incoming stimulation than before and is said to be _______________.

A) Hyperpolarized
B) Depolarized
C) Facilitated
D) Inhibited

Answer 1

A neuron that is more excitable due to excitatory but subthreshold stimuli is considered facilitated.

Step-by-step explanation:

If a neuron receives a series of stimuli whose effect is excitatory but subthreshold, the neuron is more excitable to incoming stimulation than before and is said to be facilitated. This condition does not refer to a complete depolarization or an action potential firing; instead, it suggests that the neuron is near the threshold and thus requires less additional stimuli to reach the threshold and trigger an action potential. The term facilitated describes this state of increased excitability due to prior subthreshold excitatory postsynaptic potentials (EPSPs) that have incrementally depolarized the neuron closer to the action potential threshold without actually reaching it.