The PAG is to the raphé as
A) opiate 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) is a brain region involved in pain modulation, while the raphé nuclei are a group of brainstem nuclei that produce serotonin. Opiates are drugs that bind to opioid receptors in the PAG and raphé nuclei, producing analgesia.

The PAG Is to the Raphé as