Serotonin

Serotonin is one of several chemical messengers in the brain, or neurotransmitters, which help brain cells communicate with one another. Among many other functions, serotonin is involved in regulating mood. Problems with making or using the right amount of serotonin have been linked to many mental disorders, including depression, bipolar disorder, anxiety disorder, autism, and schizophrenia.

What is Serotonin?

Serotonin is an example of a neurotransmitter, a chemical messenger that is passed between nerve cells. When a nerve impulse reaches the axon at the end of a nerve, neurotransmitters are released which cross an area called the synapse to be received by a specific receptor on the end of a target nerve. Once received by the target nerve, the neurotransmitter may either excite that nerve to fire its own signal or prevent it from firing the signal.

Serotonin Pathology

The Relationship Between Serotonin and 5-HTP

Serotonin Biosynthesis

Serotonin in Plants

Serotonin and Aggression

Drugs Targeting the 5-HT System

Serotonin Function

Do Serotonin and Antidepressants Affect the Microbiome?

Latest Serotonin News and Research

Eating walnuts daily may boost mood and shift serotonin-related metabolism

Daily walnuts improve mood and alter serotonin-related metabolites in young adults.

2 Oct 2026

New framework maps the complex link between psychological status and cardiovascular health

CVD remains the leading cause of death worldwide, while the global burden of mental disorders continues to rise.

28 Sep 2026

Smart contact lens measures stress levels by analyzing human tears

A research team led by Dr. Yangzhi Zhu, Principal Investigator and Assistant Professor at the Terasaki Institute for Biomedical Innovation (TIBI), has developed a soft, reusable smart contact lens as part of its broader Ocular Library for the Analysis of Tear Biomarkers (OCULAB), a tear bioelectronics platform for noninvasive, longitudinal biochemical monitoring through the ocular surface and tear film.

24 Sep 2026

Scientists discover the molecular mechanism behind instantaneous memory formation

The National Institute of Information and Communications Technology (NICT, President: OHNO Hideo, Ph.D.) has discovered molecular mechanism of synaptic facilitation, instantaneous strengthening of synaptic transmission, which may be physiological basis of instantaneous memory.

24 Sep 2026

Less is more: Exercise rivals common pain meds

From osteoarthritis to a splitting migraine, when you’re experiencing pain, exercise can seem like the last thing you want or think you should do. But according to new Adelaide University research it could be one of the most effective ways to help ease your symptoms.

24 Sep 2026

Exercise offers broad pain relief across acute and chronic conditions

From osteoarthritis to a splitting migraine, when you're experiencing pain, exercise can seem like the last thing you want or think you should do. But according to new Adelaide University research it could be one of the most effective ways to help ease your symptoms.

23 Sep 2026

Prenatal cannabis exposure linked to subtle brain and behavioral differences in children

A large ABCD study of 10,838 children found that prenatal cannabis exposure was associated with small differences in resting-state brain connectivity, higher behavioral and emotional problem scores, and lower performance on several cognitive measures in late childhood. PCE-related connectivity patterns partly overlapped with those linked to psychopathology and cognition, although the cross-sectional observational design cannot establish causality or mediation.

22 Sep 2026

Study identifies brain mechanism behind pregnancy-related food cravings

Why do food cravings become so strong during pregnancy? Researchers at LSU's Pennington Biomedical Research Center, in collaboration with colleagues, have identified a brain mechanism that may help explain how pregnancy changes the motivation to seek certain highly palatable foods.

18 Sep 2026

Shatavari may affect more than hormones, and the gut could help explain why

A review in Nutrients examined how bioactive compounds in Asparagus racemosus (Shatavari) may influence cognitive health through the microbiota-gut-brain axis, estrogen-related signaling, neuroinflammation, oxidative stress, and neurotransmitter regulation. Evidence from computational, cellular, animal, and limited human studies suggests several plausible biological pathways, but key questions remain about bioavailability, brain exposure, dosing, and clinical efficacy.

16 Sep 2026

Add-on drug lumateperone boosts sexual function in patients with depression

Patients with major depressive disorder (MDD) and an inadequate response to standard antidepressants who received an add- on treatment with the drug lumateperone saw significantly improved sexual function, found a new study led by a University of Virginia School of Medicine researcher.

15 Sep 2026

A study of more than 21,000 adults found an unusual link between psilocybin and diet

Using data from more than 21,800 adults in two UK birth cohorts, researchers found that lifetime psilocybin and LSD use was associated with stronger pro-environmental attitudes and a greater likelihood of following a vegetarian diet, with psilocybin showing the clearer dietary pattern. Mediation analyses suggested that environmental attitudes statistically accounted for the psilocybin-vegetarianism association and part of the association with lower red meat consumption, but the observational design cannot establish causation.

15 Sep 2026

A study of ayahuasca users found a mental health pattern researchers cannot yet explain

In a cross-sectional study of 808 Brazilian adults planning to attend ayahuasca ceremonies, greater prior experience with the brew was associated with lower depression, anxiety, and stress scores, as well as higher spiritual well-being and stronger metaphysical beliefs. Because the study was observational and relied on self-reported data, it cannot show that ayahuasca caused these differences.

13 Sep 2026

Review highlights solute carriers as targets for central nervous system disorders

Solute carriers (SLCs) are specialized transport proteins that control the movement of nutrients, ions and neurotransmitters across cell membranes and are essential for brain metabolism and neuronal communication.

10 Sep 2026

LSD deconstruction reveals promising new drug candidates

University of California, Davis researchers have stripped down LSD to the base features responsible for its hallucinogenic and therapeutic effects.

7 Sep 2026

What your gut microbes may have to do with how your brain ages

This review examines how diet-driven changes in the gut microbiota and microbial metabolites may influence cognitive aging through immune, metabolic, neural, endocrine, and barrier-related pathways. It highlights SCFAs, tryptophan-derived metabolites, and bile acids as key signaling mediators while emphasizing that much of the mechanistic evidence remains preclinical and human evidence is largely associative.

3 Sep 2026

What your genes can, and cannot, tell us about your personality

A meta-analysis of 46 cohorts involving 611,037 to 1.14 million participants identified 1,260 lead genetic variants associated with the Big Five personality traits, including 824 in previously unlinked genomic regions. The associations were broadly consistent across cohorts and measurement contexts, while polygenic analyses linked personality-related genetics to health, behavior, psychopathology, and life outcomes, although effects were modest and could not predict individual behavior.

3 Sep 2026

Does a psychedelic need an awake brain to have lasting effects? This mouse study offers a clue

A single dose of psilocybin produced a lasting increase in sociability for at least two weeks in Cntnap2-knockout mice with social deficits, while it did not enhance sociability overall in mice with normal social behavior. The effect required 5-HT2A receptor activation and persisted when psilocybin was administered under light anesthesia, suggesting that wakefulness during the drug’s acute effects was not necessary for this behavioral response.

30 Aug 2026

Probiotics for mental health? A new review finds promising signals and major gaps

This narrative review examines how psychobiotics may influence anxiety, depression, bipolar disorder, and schizophrenia through gut-brain pathways involving neurotransmitters, inflammation, immune regulation, gut barrier function, and stress signaling. Specific Lactobacillus and Bifidobacterium strains showed encouraging effects, but wide differences in strains, doses, populations, and study designs currently limit clinical translation.

28 Aug 2026