Schizophrenia and neurodevelopmental disorders

The essentials

Schizophrenia is a group of psychotic disorders in which personal, social and occupational functioning deteriorate due to disturbed thought processes, strange perceptions, unusual emotional states and motor abnormalities. Its symptoms fall into three groups.

Key points

• Positive symptoms (excesses of thought, emotion and behaviour): delusions (false beliefs held firmly despite no basis, such as delusions of persecution, reference, grandeur and control), disorganised thinking and speech (formal thought disorder, derailment or loosening of associations, neologisms, perseveration, clang), hallucinations (perceptions without external stimuli; auditory hallucinations are most common) and inappropriate affect.
• Negative symptoms (deficits): alogia (poverty of speech), blunted or flat affect, avolition (inability to start or complete a course of action) and social withdrawal.
• Psychomotor symptoms: awkward movements, catatonia (extreme reduced activity; catatonic stupor, rigidity and posturing).
• Excess dopamine activity has been linked with schizophrenia.
• Neurodevelopmental disorders appear early in development and affect personal, social, academic or occupational functioning.
• ADHD (attention-deficit/hyperactivity disorder): main features are inattention and hyperactivity-impulsivity.
• Autism spectrum disorder: difficulties in social interaction and communication, restricted interests and a strong need for routine; many children with ASD also have some intellectual disability, though some show special skills.
• Intellectual disability and specific learning disorder (difficulty in reading, writing or arithmetic despite normal intelligence) are also neurodevelopmental.

Exam tips

• Positive symptoms are "added" experiences (hallucinations, delusions); negative symptoms are "missing" functions (alogia, flat affect, avolition).

Common mistakes

• Schizophrenia does not mean "split" or multiple personality; that is dissociative identity disorder.
• A hallucination is a false perception; a delusion is a false belief.