Psychiatry: Schizophrenia
Diagnostic Criteria and Forensic Implications
Schizophrenia is a chronic, severe mental disorder characterized by distortions in thinking, perception, emotions, language, sense of self, and behavior.
1. Diagnostic Criteria (DSM-5)
Requires two or more of the following for a significant portion of time during 1 month, with continuous signs of disturbance for at least 6 months:
- Delusions
- Hallucinations (most commonly auditory)
- Disorganized speech
- Grossly disorganized or catatonic behavior
- Negative symptoms (avolition, flat affect, anhedonia)
2. Clinical Subtypes & Features
| Feature | Description |
|---|---|
| Positive Symptoms | Added features: Delusions, hallucinations, agitation. |
| Negative Symptoms | Loss of normal function: Avolition, alogia, anhedonia. |
| Cognitive Symptoms | Deficits in memory, attention, and executive function. |
3. NEET PG High-Yield Pearls
- Schneider’s First-Rank Symptoms: Auditory hallucinations (running commentary, voices arguing), thought insertion/withdrawal/broadcasting, and passivity experiences.
- Dopamine Hypothesis: Hyperactivity of dopamine in the mesolimbic pathway causes positive symptoms, while hypoactivity in the mesocortical pathway causes negative symptoms.
- Forensic Link: Schizophrenia is the most common psychiatric diagnosis associated with the insanity defense in cases of violence, particularly when command hallucinations are present.
- Treatment: Primarily antipsychotics (dopamine receptor antagonists). Clozapine is the treatment of choice for treatment-resistant cases.