Serotonin is in the brain. It is thought to regulate mood, happiness, and anxiety. Low levels of serotonin are linked to depression, while increased levels of the hormone may decrease arousal.

What does the release of serotonin do?

Mood: Serotonin in the brain is thought to regulate anxiety, happiness, and mood. Low levels of the chemical have been associated with depression, and increased serotonin levels brought on by medication are thought to decrease arousal.

When does your brain release serotonin?

When brain cells send signals to one another, they release neurotransmitters, including serotonin. Before they can send the next signal, the cells must reabsorb and recycle the neurotransmitters they released. This process is called reuptake.