Sz explanations

Cards (38)

  • - the genetic theory
    - dopamine hypothesis
    - neural correlates

    what are the 3 biological explanations of sz?
  • sz caused by genes passed down from biological parent to child, the closer related you are to someone with sz, the more likely you are to develop it

    what does the genetic theory argue is the cause of sz?
  • 108, different combinations or single genes, so is polygenic
    how many different genes are associated with the risk of sz?
  • study found that MZ twins reared apart were 58% concordant, suggesting that genetics have an influence as concordance rates are high. HOWEVER, MZ twins share 100% same genes so if it was just due to genetics the rate would be 100%, therfore environmental influence must have a role

    give a twin study that supports the genetic theory
  • 47 adopted children (mothers had sz) were compared to control gorup with no history of family sz. Found 16% group developed sz whereas 0% from control group, suggesting genetics must play a role

    give another supporting study of the role of genetics in sz?
  • 1930, identical quadruplet sisters who all developed sz, they had a bad home life with mentally unstable parents. Supports theory as shared 100% same genes and all devloped sz, HOWEVER bad homelife environmnetal factor could have increase likelyhood to develop sz

    who were the genain quadruplets? how do they support the genetic theory?
  • considered socially sensitive as puts blame on parents if child develops sz, and if children know they are at high likelihood of developing sz, they are more likely to develop it. HOWEVER, could stop them from triggering factors e.g. smoking
    what is a negative of the genetic theory?
  • generic counselling, supports high risk people and uses environmental interventions to reduce the risk

    what are the practical applications of the genetic theory?
  • vulnerability may not be triggered unless there are certain environmental factors/ stressors present

    what is the diathesis-stress theory?
  • symptoms of sz caused by abnormal levels of neurotransmitter dopamine, (excitatory which increases rate of firing)
    what is the dopamine hypothesis?
  • - hyperdopaminergia
    - hypodopaminergia
    what are the 2 possible effects of dopamine?
  • higher than usual levels of dopamine in the subcortex (central areas of the brain), linked with positive symptoms.
    define hyperdopaminergia
  • lower than usual levels of dopamine in the cortex (outer part of the brain), where less dopamine is being transmitted across synapses, linked with negative symptoms.

    define hypodopaminergia.
  • higher levels of dopamine in post-mortems conducted on patients with sz compared to patients with no sz, supports higher rates of dopamine linked to sz. HOWEVER, only correlation, no cause and effect relationship, therefore where dopamine levels high before or after developing sz?

    describe the post-mortem study and how it supported the dopamine hypothesis.
  • anti-psychotics are effective treamtnet of sz and work by decreasing dopamine levels, therefore clear link between antipsychotics and dopamine treating sz. HOWEVER, treatment-aetiology fallacy shouldn't be made because it could just be masking the symptoms.

    explain how antipsychotic evidence support the dopamine hypothesis?
  • the measurements of the structure or function of the brain that correlate with experiences or behaviours (e.g. sz)
    what are neural correlates?
  • + excessive dopamine receptors have been found in Broca's area (involved in language production)
    + adds support to the excess of dopamine leading to positive symptoms (e.g hallucinations)

    how do neural correlates explain positive symptoms of Sz
  • - 1 explanation is Sz is caused by enlarged ventricles: these are fluid filled cavities, estimates to be 15% larger in people with Sz (lessens brain weight)
    - implies brain areas around border of ventricles have shrunk, so ventricular spaces became larger as a result

    how do neural correlates explain negative symptoms of Sz
  • all correlations- remains unclear whether the unusual activity or abnormality in brain areas is the cause of the sz or a symptom of having the disorder/taking medication
    what is an issue with neural correlates?
  • family dysfunction
    cognitive explanation
    what are the 2 psychological explanations of sz?
  • - schizophrenogenic mother
    - double blind theory
    - expressed emotion
    at are the 3 main ideas of family dysfunction?
  • argues that maladaptive relationships and communication between family members in a source of stress leading to sz

    what does family dysfunction argue that the cause of sz is?
  • a psychodynamic explanation where the mother is cold, rejecting and controlling, creating a family climate of tension and secrecy. This leads to distrust that develops to paranoid delusions and then sz
    explain how a schizophrogenic mother leads to sz?
  • communication in the family is an important risk factor, theory proposes that symptoms of sz are an expression of contradictory patterns of interaction in the family, leading to delusions and disorganised thoughts
    explain how the double blind theory leads to sz?
  • expressed emotion is a qualitative measure of amount of emotion expressed, measures prediction of relapse in sz. expressed emotions include: hostility towards patient, emotional over-involvement and crisitcism of patient

    explain how expressed emotion leads to sz?
  • relapse in high EE is 48% compared to 21% in low, supports expressed emotion might trigger relapse
    give some statistics for relapse rates in high EE vs low EE environments?
  • + adults with insecure attachment more likely to develop sz, suggesting secure bond with parents is important
    + practical applications, put recovering patients in low EE environments

    give the posititves of the family dysfunction explanation?
  • - lower validity if patients recall childhood memories as may not be accurate or could be recalling delusions/ hallucinations
    - socially sensitive, blames parents could cause them to become high EE
    - unsure if high EE is a symptom or a cause
    - hard toc lassify family as high/ low EE as families often changing
    give the negatives of the family dysfunction explanation?
  • arguesd that behaviours like sz are result of faulty mental processing and cognitive biases (focuses of attention)

    what is the main belief of the cognitive approach?
  • sz patients often have defecits in working memory which can impact their ability to engage in complex cognitive trials. impairment may cause difficulties in organising thoughts, maintaining attention and problem solving

    explain how a person with sz's memory may be impaired according to the cognitive explanation?
  • sz is associated with dysfunctional thought processing, they have cognitive bias where they see themselves as being targeted, leading to belief that they are under control and thoughts are being implanted in their head

    explain how a person with sz's thinking may be impaired according to the cognitive explanation?
  • 1) metarepresentation dysfunction
    2) central control dysfunction

    what are the two specific dysfunctional thought processes according to the cognitive explanation?
  • the ability to reflect on our thoughts and behaviours and allows us insight into our own intentions and goals and interpretation of the actions of others.
    define metarepresentation.
  • disrupt our ability to recognise our own actions and thoughts as being carried out by ourselves, - delusions
    what is a dysfunction in metarepresentation? what symptom of sz could this explain?
  • ability to suppress or override automatic thoughts, actions and speech in response to stimuli
    what is the central control?
  • derailment of thoughts and spoken sentences because each word triggers associations and the patient cannot supress automatic responses to these- speech poverty + disorganised language

    what is a dysfunction in central control? what symptoms of sz could this explain?
  • + research evidence, sz patients look twice as long as control patients to name the font colour of colour words in a STOOP test, showing dysfunction in cognitive control
    + practical applications, CBT
    give some strengths of the cognitive explanation of sz?
  • - incomplete explanation, cognitive defecits do not explain the causes of cognitive defecits
    - problem with cause and effect, is it cognitive defectis which causes sz behaviour or is the sz that causes the cognitive defecits?

    give some weaknesses of the cognitive explanation of sz?