Schizophrenia is a chronic psychiatric disorder marked by disturbances in perception, thinking, emotion and behavior. Core symptoms include hallucinations, delusions, disorganized speech and behavior, and negative symptoms such as lack of motivation, blunted affect and social withdrawal. Onset typically occurs in late adolescence or early adulthood and the course often involves relapses and remissions.

Research indicates that schizophrenia arises from a complex interplay of genetic vulnerability and environmental exposures. Family and twin studies show strong heritability, but no single gene is responsible. Instead, many genetic variants each confer small increases in risk. Environmental factors under active investigation include prenatal complications, maternal infections, early-life adversity, urban upbringing, migration and cannabis use, especially during adolescence.

At the brain level, structural imaging frequently reveals subtle reductions in gray matter volume, particularly in frontal and temporal regions, as well as changes in connectivity among key networks involved in cognition and emotion. Neurochemical studies support dysregulation of dopamine and glutamate signaling, helping explain positive symptoms and cognitive deficits.

Current treatments center on antipsychotic medications that primarily target dopamine receptors, often reducing hallucinations and delusions but less effectively addressing negative and cognitive symptoms. Psychosocial interventions, including cognitive behavioral therapy, family-based approaches, social skills training and supported employment, improve functioning and quality of life. Early detection programs aim to identify individuals at high risk or in the prodromal phase to begin support and treatment as soon as possible.

Ongoing research is directed at clarifying causal mechanisms, refining early identification, developing drugs that target additional neurotransmitter systems and tailoring interventions to individual biological and clinical profiles.