Written by the Fiveable Content Team โข Last updated September 2025
Verified for the 2026 exam
Verified for the 2026 examโขWritten by the Fiveable Content Team โข Last updated September 2025
Definition
Serotonin levels refer to the amount of serotonin, a neurotransmitter, present in the brain. This neurotransmitter plays a crucial role in regulating mood, sleep, appetite, and other physiological functions.