Classification of Schizophrenia

• positive symptoms

  hallucinations and delusions
• hallucinations

  perception-like experiences that are not under voluntary control

  - can occur in any of the 5 senses

  - most common is auditory
• What are delusions?

  Fixed beliefs that are hard to change even when given conflicting evidence
• What are the types of delusions?

  Persecutory, referential, and grandiose.
• negative symptoms

  speech poverty and avolition
• speech poverty


  speaking infrequently and not engaging in conversation, speech is disorganized
• what is speech poverty often accompanied by?


  reductions in expressions and eye contact
• avolition


  lack of motivation to do anything, may sit for long periods of time

  can also involve anhedonia: inability to experience pleasure from positive stimuli
• 2 classification systems

  ICD-11 and DSM-5
• ICD-11

  classification system in the UK and Europe, the individual must show at least 1 major and 2 less serious symptoms
• DSM-5

  classification in the US, the individual must show at least 2 major symptoms for a significant period
• which classification system can have subtypes?

  ICD-11
• Rosenhan study 1: aim

  to test whether sane individuals who presented themselves at a psychiatric hospital would be diagnosed as insane
• pseudopatients in Rosenhan's study

  5 men and 3 women of different occupations
• who were the participants in Rosenhan's first study?

  the hospital staff
• how many hospitals were used in Rosenhan's study?

  12
• Rosenhan: procedure


  each pseudopatient called the hospital saying they were hearing voices
• Rosenhan: results


  all pseudopatients were admitted to hospital and all but 1 were diagnosed with schizophrenia. they were held in hospital for an average of 19 days
• how were pseudopatients treated after being admitted?

  they were shouted at and beaten by staff, seen in the light of their label and made to feel powerless
• medication in Rosenhan's study

  pseudopatients were given medication but secretly didn't take it - the staff never checked whether or not they took it
• who were the pseudopatients mainly challenged by?

  other patients
• why was the pseudopatients' behaviour abnormal?

  they were worried about being exposed as a fraud and shocked when they were admitted
• Rosenhan study 2: aim

  to see if psychiatrists could identify pseudopatients in a psychiatric hospital
• rosenhan study 2: procedure

  staff were asked to rate all admissions over 3 months from 1-10 on the likelihood of them being a pseudopatient
• rosenhan study 2: results

  193 patients were admitted and 83 were suspected to pseudopatients by at least one staff member
• how many patients in rosenhan's 2nd study were pseudopatients?

  none of them
• 6 issues in diagnosis of schizophrenia

  - validity

  - reliability

  - co-morbidity

  - symptom overlap

  - cultural bias

  - gender bias
• reliability


  the same diagnosis is given for the same symptoms

  - measured in concordance
• validity


  when a psychiatrist diagnoses a condition correctly
• co-morbidity


  having other disorders such as depression and anxiety alongside schizophrenia
• symptom overlap


  symptoms of schizophrenia can be found in other disorders e.g delusions can be symptoms of bipolar
• cultural bias


  african-caribbean people are more likely to be diagnosed with schizophrenia as culture affects how it is reported and diagnosed
• cultural bias - category failure

  western definitions are applied to non western cultures e.g. hearing voices of angels would be seen as a hallucination in the Uk, but a religious experience in the west indies
• gender bias


  men are more likely to be diagnosed with schizophrenia than women however women may be better at functioning in everyday life so may be less likely to seek treatment