Schizophrenia

Abstract

Schizophrenia is a complex and multifaceted psychotic disorder that affects millions of people worldwide. It is characterized by positive symptoms, such as hallucinations and delusions, negative symptoms, including avolition and anhedonia, and persistent cognitive impairments that significantly disrupt daily functioning. The disorder typically emerges in early adulthood, with distinct variations in symptom presentation and onset age between males and females. Historically misinterpreted as madness or spiritual disturbance, schizophrenia is now recognized as a neurodevelopmental disorder with both genetic and environmental contributions. The disorder carries a high burden on affected individuals, caregivers, and healthcare systems, particularly due to its treatment resistance and association with premature mortality. The current understanding of schizophrenia reflects multifactorial origins. Genetic studies highlight a strong heritable component, supported by twin concordance rates and genome-wide association studies. Neuroimaging reveals structural brain differences, including reduced gray and white matter volumes and enlarged lateral ventricles, which may correlate with symptom severity. Environmental factors such as prenatal complications, childhood adversity, psychosocial stressors, and adolescent substance use contribute to the disorder’s onset and progression. Diagnosis relies on criteria set forth by the DSM-5, which emphasizes symptom duration and functional impairment. Treatments include pharmacological interventions and psychosocial therapies such as cognitive behavioral therapy, social skills training, and family psychoeducation. Despite available interventions, approximately one-third of individuals with schizophrenia are resistant to standard treatment, prompting the use of medications like clozapine and exploration of adjunctive methods such as electroconvulsive therapy. Recent research focuses on improving outcomes for negative and cognitive symptoms through novel medications targeting various neurotransmitters, neuroinflammation, and cholinergic pathways. Lifestyle-based interventions, including exercise and the role of the microbiome, are also gaining traction as complementary treatment strategies.