American Board of Psychiatry and Neurology (ABPN) Practice Exam 2025 - Free ABPN Practice Questions and Study Guide

The neurotransmitter synthesized in the locus ceruleus is norepinephrine. The locus ceruleus is a key nucleus located in the brainstem that plays a crucial role in the regulation of arousal, attention, and stress response. It is primarily involved in the synthesis and release of norepinephrine, which affects various physiological and psychological processes, including mood regulation, alertness, and the fight-or-flight response.

Norepinephrine acts as both a neurotransmitter and a hormone and is vital in the central nervous system's functioning. The activity of the locus ceruleus is significantly associated with various psychiatric conditions, including anxiety and depression, which illustrates the importance of norepinephrine in mental health.

Other neurotransmitters listed in the options serve different roles and are synthesized in other areas of the brain. For example, dopamine is predominantly synthesized in areas such as the ventral tegmental area and substantia nigra, serotonin is primarily produced in the raphe nuclei, and acetylcholine is synthesized in various locations, including the basal forebrain. Therefore, while these neurotransmitters are also crucial for brain function and mental health, the specific synthesis of norepinephrine takes place in the locus ceruleus.