Stimulation of a neuron that terminates in the superior region of the left postcentral gyrus would produce
A) a sensation in the right leg.
B) a sensation in the lips.
C) a muscle twitch in the right leg.
D) a muscle twitch in the lips.
E) both sensations and muscle twitches in the right leg.

Question

Quizplus · Accepted Answer

The superior region of the left postcentral gyrus is part of the primary somatosensory cortex, which is responsible for processing sensory information from the opposite side of the body. Since this area is involved in sensation rather than motor control, stimulating it would produce a sensation (not a muscle twitch) in the contralateral (opposite) side of the body. The superior region specifically processes sensations from the lower body, including the legs, so the correct answer is a sensation in the right leg.

Stimulation of a Neuron That Terminates in the Superior Region