AO1

• Schizophrenia - a psychotic disorder involving a break in reality which involves a disruption of cognition and emotion
• Acute (type I) schizophrenia has more positive symptoms and responds well to treatment.
• Chronic (type II) schizophrenia has more of the negative symptoms and is less responsive to treatment.
• Positive symptoms - thought disorders, auditory hallucinations, primary delusions
• Negative symptoms - disturbances of effect, avolition, psychomotor disturbances, thought process disorders
• Issues with the classification and diagnosis of schizophrenia are validity and reliability
• Validity refers to the extent that a diagnosis represents something that is real and distinct from other disorders and whether the ICD or DSM measure what they claim to measure.
• Inter-rater reliability refers to the extent that two clinicians will reach the same diagnosis. Test-retest reliability is whether the same diagnosis is reached for the same individual on two occasions by one clinician. Historically, reliability for diagnosis of Schizophrenia has been low but recent studies suggest higher reliability.
• Positive symptoms are additional experiences that are beyond theose of ordinary existence
• Negative symptoms are losses of normal experiences and abilities
• Avolition - lack of purposeful behaviour, lack of motivation, lack of interest, lack of energy
• Disturbances of effect - sufferers appear uncaring of others, display inappropriate emotional responses or display sudden mood swings
• Psychomotor disturbances - sufferers adopt frozen 'statue-like' poses, exhibit tics and twitches and repetitive behaviours