schizophrenia

• what is test- retest reliability ?

  when psychiatrists must be able to reach the same conclusion at two different points in time
• what is inter-rater reliability?

  when psychiatrists reach the same conclusion of the same patient
• What is inter-rater reliability measured in?

  Kappa score
• What is a kappa score?

  A score from 0 to 1. 0 being zero agreement and 1 being inter-rater agreement
• what kappa score is considered good reliability?

  +0.7 or above
• what is reliability in schizophrenia?

  when a diagnosis must be consistent and repeatable.
• what are the two types of reliability

  test-retest and inter-rater
• what are the two reliability threats?

  cultural differences and comorbidity
• explain cultural differences in diagnosis

  culture has a influence on the diagnosis process, Luhrmann studied people with SZ from Ghana, India and USA. Ghanaian and indian reported positive experience with hallucination but no American did. Hallucinations can be different in one part of the world and different in another. Threatens validity
• What is comorbidity? give examples

  it refers to the extent that two or more conditions co-exist. E.G substance abuse, anxiety,panic disorder.
• what is an evaluation for cultural differences?

  schizophrenia can be as much as five times higher in some ethnic minority. E.G black Caribbean or African in the UK. This is not genetic as there is no such pattern in those countries. (p) this is due to culture bias in diagnosis of patients. (e) Threat to reliability, lacks inter-rater reliability
• what are 2 positive symptoms of schizophrenia?

  Hallucinations, Delusions
• what are two negative symptoms of schizophrenia?


  avolition and speech poverty (alogia)
• what is comorbidity?

  when two or more conditions co-exist
• what is an evaluation of comorbidity?

  • schizophrenics do have issues with substance abuse
  • it lowers compliance with medication
  • supports the issue of comorbidity affecting the reliability of a diagnosing schizophrenia
  • + schizophrenics with comorbidity are excluded from research
• what is validity in schizophrenia?

  how accurate a diagnosis is
• what are 2 threats of validity?

  symptom overlap and gender bias in diagnosis
• what is symptom overlap?

  When different disorders have similar symptoms
• evaluate symptom overlap


  • SZ is to difficult to accurately diagnose
  • in Japan they believe sz as a separate, does not exist. this is due to its complex and varying nature.
  • we cannot accurately diagnose sz as a single illness, it threatens the validity
  • +an incorrect diagnose can lead to a self fulfilling prophecy, and wrong medication can lead to side effects.
• what is gender bias in diagnosis?


  Men have been diagnosed with sz more frequently than women.

  Males tend to suffer more negative symptoms.

  females have better recovery rates and lower relapse rates.
• evaluation of gender bias

  • research supports gender diffrences in treatment
  • males could more likely be hospitalised in psychiatric hospitals, whereas women are voluntary patients has they are likely to seek help earlier.
  • supports the idea that gender bias exists
  • + a consequence is that it is androcentric
• overall evaluation on validity


  • no evidence that sz patients share the same outcomes
  • the prognosis varies for every 5 people with sz
  • a diagnosis can have little predictive validity- some people never appear to recover, but many do.
  • + what influences the out come is more to do with gender and psycho-social factors such as social skills.
• what are twin studies?


  • the degree which if one twin has sz the other twin has it.
  • they primary focus on monozygotic twins who share 100% of their genes.
  • if monozygotic twins are more concordant than dizygotic then this suggests greater similarity is due to genetic factors.
• what are family studies?


  they establish that sz is more common among biological relatives of a person with sz, and that the closer the degree of genetic relatedness the greater the risk
• what are adoption studies?


  Research studies that examine the similarities between biological relatives and adopted individuals to determine the influence of genetics and environment on traits or behaviour.
• what are gene mapping studies?


  they look at genetic material commonly found among sufferers.
• evaluation for twin studies

  • supporting research
  • they reported a concordance rate between 75% and 91% of M.Z, this suggests that genetics play a larger role with chronic forms of the disorder.
  • sz is inherited, as identical twins have 100% shared genes and non identical have 50%
  • however if genes caused sz on their own the concordance rate in M.Z twins would be 100%, which they are not.
• what is hyperdopaminergia?


  Too much dopamine
• explain hyperdopaminergia?

  excess dopamine receptors in the Broca's area may be associated with speech poverty and auditory hallucinations (pos and neg symptoms)
• what is hypodopaminergia?

  low levels of dopamine in the prefrontal cortex

  negative symptoms of sz
• evaluation of dopamine hypothesis


  • animal studies show support
  • sz behaviour in rats, amphetamine speed up dopamine activity
  • symptoms include hissing, spitting and aggression
  • adds credibility
  • However its anthropomorphism - problem generalising from animal to humans
• evaluation for dopamine hypothesis


  • not bias , scientific
  • PET and MRI , found out that sz have high dopamine receptors in key areas of the brain
• what are neural correlates?

  measures of the structure or function of the brain that correlate with an experience e.g sz
• ventricles provide the supporting fluid of the brain. If there is damage to the brain and parts of it die then the ventricles will enlarge to fill the space left, so ventricular enlargement is often a good indicator of brain damage
• what is ventral striatum? (negative symptoms)


  Brain region involved in reward and motivation.
• In neural correlates of positive symptoms areas of the brain involved in speech and language are being activated during auditory hallucinations.
• evaluation for neural correlates

  • supporting evidence
  • fMRI where used in 18 sz and 19 non sz performing a memory task
  • there was a decreased activity in the prefrontal cortex
  • may be related to the cognitive deficits experienced with sz
• what does double bind communication mean?

  when a verbal message is given but opposite behaviour is exhibited.

  The child receives two conflicting messages
• positive symptoms of double bind?

  disorganised thinking and paranoid delusions
• negative symptoms of double bind?

  social withdraw and lack of emotional expression