If a researcher was exploring a possible link between the activity of serotonergic neurons and behavioral traits in a group of people with personality disorders, she might measure in _______ in these subjects.
A) levels of 5-HIAA in the CSF
B) levels of 5-HIAA in the bloodstream
C) levels of 5-HT in the CSF
D) activity of SERT

Question

Quizplus · Accepted Answer

The best choice would be to measure levels of 5-HIAA (a metabolite of serotonin) in the cerebrospinal fluid (CSF) as it reflects the activity of serotonergic neurons in the brain. Bloodstream levels of 5-HIAA may not accurately reflect brain activity due to the blood-brain barrier. Measuring levels of 5-HT (serotonin) in the CSF would reflect the amount of serotonin present, but not necessarily the activity of serotonergic neurons. Activity of the serotonin transporter (SERT) would also not directly measure the activity of serotonergic neurons, as blocking/reducing SERT activity can have indirect effects on serotonin signaling.

If a Researcher Was Exploring a Possible Link Between the Activity