Chapter 4: Psychosis

Raskin explores schizophrenia spectrum and other psychotic disorders, conditions marked by disturbances in perception, thought, emotion, and behavior that profoundly disrupt functioning. The chapter begins with clinical case studies that illustrate hallmark symptoms: hallucinations, delusions, disorganized speech, grossly disorganized or catatonic behavior, and negative symptoms such as flat affect, avolition, and anhedonia. It reviews diagnostic criteria in both DSM-5-TR and ICD-11, clarifying their categorical and dimensional approaches and the importance of diagnostic reliability and validity. The spectrum includes schizophrenia, schizoaffective disorder, delusional disorder, brief psychotic disorder, schizophreniform disorder, and schizotypal personality disorder. Subtypes once recognized (such as paranoid or catatonic schizophrenia) are no longer official diagnoses but remain clinically descriptive. Biological perspectives highlight genetic heritability, neurodevelopmental models, dopamine and glutamate hypotheses, brain structure abnormalities, and prenatal and perinatal risk factors. Psychological and sociocultural perspectives explore trauma, stress-vulnerability models, family systems theories, expressed emotion, cognitive explanations for delusions and thought disorder, and the influence of poverty, discrimination, and migration. Historical approaches trace shifts from moral judgments and asylums to Emil Kraepelin’s early classification, Bleuler’s coining of “schizophrenia,” and the changing place of psychosis within DSM editions. Treatment strategies are reviewed in depth, including first- and second-generation antipsychotics, their mechanisms and side effects (extrapyramidal symptoms, tardive dyskinesia, metabolic syndrome), electroconvulsive therapy, transcranial magnetic stimulation, cognitive-behavioral therapy for psychosis, family interventions, and the Hearing Voices movement that emphasizes meaning-making rather than symptom suppression. The chapter also critiques psychiatric labeling, stigma, and cultural assumptions that shape diagnosis, with attention to cross-cultural variations in hallucinations and outcomes. By the end, students learn that schizophrenia spectrum disorders cannot be reduced to a single cause or treatment: they are best understood through an integrated biopsychosocial model that considers biological vulnerability, psychological processes, and sociocultural context together.