Serotonin research: contributions to understanding psychoses

Abstract

The history of serotonin research is closely related to the study of hallucinogenic drugs that function as agonists at serotonin-2A receptors. The fundamental idea that psychotic states seen in psychiatric disorders such as schizophrenia might be attributable, in part, to abnormalities in serotonergic systems began with the almost simultaneous discovery of lysergic acid diethylamide (LSD), psilocybin and serotonin. Sixty years of study have confirmed early speculations regarding the important relationship between serotonin and both drug-induced and disorder-based psychotic states. Now, modern biochemical, pharmacological, behavioral, neuroimaging, genetic and molecular biological sciences are converging to understand how serotonergic systems interact with other monoaminergic and glutamatergic systems to modulate states of consciousness and contribute to psychotic disorders such as the group of schizophrenias. This review summarizes experimental assessments of the serotonergic hallucinogen model psychosis in relation to the serotonin hypothesis of schizophrenia.

In the evidence

This study is part of the evidence base for a synthesis in the library. Here is how each one recorded it.

• State of the evidence: LSD ↑Supports

  Sixty years of research support a relationship between serotonin, serotonergic hallucinogens, and both drug-induced and disorder-based psychotic states.

  Synthesized October 19, 2026

Comparable studies

Other narrative reviews on serotonin, most cited first.