The PAG is to the raphé as
A) opioid is to serotonin.
B) serotonin is to opiate.
C) pain is to analgesia.
D) analgesia is to pain.
E) descending is to ascending.

Question

Quizplus · Accepted Answer

The PAG (periaqueductal gray) and the raphé nuclei are both involved in pain modulation. The PAG is a brainstem structure that contains neurons that release opioids, which are neurotransmitters that inhibit pain signals. The raphé nuclei are a group of brainstem nuclei that contain neurons that release serotonin, which is a neurotransmitter that also inhibits pain signals.

The PAG Is to the Raphé as