schizophrenia

• What is schizophrenia?


  A serious disorder affecting thoughts, perceptions, behaviour and ability to communicate
• What are positive symptoms?

  Those that add something to everyday
• What are negative symptoms?


  Something that takes away from the individual
• What are examples of positive symptoms?

  hallucinations and delusions
• What are delusions?


  false beliefs that are fixed
• What are examples of negative symptoms?

  Avolition and speech poverty
• What are hallucinations?


  False perceptions that affect the senses
• What is alogia/speech poverty?


  Losing ability to speak fluently, or speech at all
• What is avolition?


  Lack of drive/motivation or inability to engage
• What is catatonic behaviour?


  Abnormal motor activity, usually a loss of motor skills/ movement
• What is used to diagnose schizophrenia?

  DSM or ICD
• What does the DSM state must be present for diagnosis?

  2 symptoms for 6 months
• Out of the two symptoms required for diagnosis, what does the DSM state one must be?

  Delusions, hallucinations or disorganised speech
• What does the ICD state must be present for diagnosis?

  One severe positive symptom for 1 month
• What is reliability?


  consistency of measurement
• What is validity?


  the degree to which a test measures what it says it measures.
• What is test-retest reliability?

  consistent diagnosis on separate occasions with same info on same person
• what is inter-rater reliability?

  several people make identical, independent diagnoses of the same patient
• What did beck find, which supports low inter-rater reliability of schizophrenia diagnosis?

  found a 54% concordance rate between diagnosis when assessing 153 patients
• What is criterion validity?


  considers whether different assessment systems reach the same diagnosis for same patient
• What are 3 issues with validity in diagnosing schizophrenia?

  Co-morbidity, cultural bias, gender bias
• What is co-morbidity?


  When two or more conditions occur together
• How does co-morbidity create issues in diagnosis?

  creates difficulties in diagnosing and treating a disorder- reduces validity
• What is culture bias in diagnosis?

  occurs when a particular culture more commonly receive a diagnosis than others
• What did Cochrane find?

  found people of Afro-Caribbean descent were 7x more likely to be diagnosed in Britain
• What is gender bias in diagnosis?

  When one gender group is treated differently, possibly under or over diagnosing that gender
• What does the biological explanation include?

  Genetic, neural and brain abnormalities
• What does the genetic explanation say about schizophrenia?

  It is transmitted through hereditary means (passed through genes)
• Who did twin studies into schizophrenia?

  Gottesman and Shields
• What did Gottesman and Shields find?

  MZ twins 42% diagnosed with schizophrenia, whereas in DZ twins only 9%
• What is schizophrenia believed to be?

  Polygenic
• What does it mean that schizophrenia is polygenic?

  Multiple genes involved
• What does it mean that schizophrenia is aetiologically heterogenous?

  Different combinations of genes can lead to Sz.
• What did Riptke et al do?


  Meta analysis of previous genome studies. Looked at 37,000 patients and 113,000 controls
• What did Riptke et al find?

  108 separate genetic variations associated with increased risk of sz
• What did Benzel et al identify?

  Three genes associated with excess dopamine
• what did Benzel et al say about the genes he identified?

  The genes (associated with excess dopamine) leads to positive symptoms
• Which three genes did Benzel et al identify?

  COMT, DRD4, ATK1
• What are the strengths of the genetic part of the biological explanation?

  Evidence from Gottesman+ Riptke showing genetic similarity increases risk of sz
• What are the weaknesses of the genetic part of the biological explanation?

  Evidence to support environmental role as well as biological factors- not a complete explanation