· Perceptual – auditory hallucinations, sometimes abusive. Other senses but rare
· Social – social withdrawal. Aloof and avoid eye contact
· Cognitive – Delusions of grandeur, paranoia, persecution, thought control, thought broadcasting, thought removal.
· Linguistic – irrelevant speech, cognitive distractibility, echolalia, word salad, nonsensical rhymes, speech poverty and neologisms
· Emotional – avolition, lack of hygiene and personal care, lack of emotion, inappropriate emotions
· Behavioural – stereotyped behaviours (constantly repeating strange actions), psychomotor disturbance, catatonic stupor
Positive v negative – positive is extra on top of current mental state, negative is lacking.
Positive symptoms are hallucinations, delusions, jumbled speech and disorganised behaviour
Negative symptoms are speech poverty, lack of emotion, avolition, dysfunction in society
DSM aims to give SZ diagnoses reliability and validity.
For a diagnosis, DSM states that an individual must show at least two of:
· Disorganised speech
· Catatonic behaviour
· Negative symptoms
At least one symptom from the top three, and present for at least 6 months with one month of active symptoms.
Reliability and Validity of diagnoses
· Cultural bias – Harrison et al 1984 found an over diagnosis of SZ in West Indian patients in Bristol. No research has found any cause for this, suggesting that symptoms were misinterpreted. Questions R of diagnosis of SZ bc it suggests patients can display same symptoms but receive different diagnoses bc of ethnic background.
· Cultural bias from medical staff themselves. Copeland et al 1971 found 69% of US psychiatrists diagnosed a video of a patient compared to 2% of British psychiatrists.
· Gender bias – Loring and Powell – 290 pzs had to diagnose same 2 patients. When told the patient was male 56% diagnosed him with sz. If told they were female, 20% diagnosed, despite them having the same symptoms. This was less apparent with female psychiatrists Therefore gender bias comes not only from gender of patient, but gender of practitioner.
· Rosenhan 1973 conducted a study where neurotypicals got admitted into psychiatric unit by saying they heard voices (pseudopatients). Once admitted they behaved normally. However all behaviour was still perceived as a symptom of their disorder by staff in the unit. Questions validity of disgnosis of mental disorder – once people are labelled as having a disorder, all their behaviour can be interpreted as being pathological.
· Symptom overlap is an issue with validity of sz. Many common symptoms in sz are found in other disorders. Eg avolition also a symptom of depression. Raises qs about what disorder the individual actually has, also drug problems – wouldn’t prescribe someone w depression antipsychotics as this would make them worse.
An issue in making a reliable and valid diagnosis of sz – two or more...