Please enable JavaScript.

Coggle requires JavaScript to display documents.

Schizophrenia (Biological explanations (The dopamine hypothesis…

- - - - Goldman - Rakic et al: Low levels of dopamine in prefrontal cortex as negative symptom of schizophrenia.
  - - - Avolition - motivation involves anticipation of reward, ventral striatum believed involved in anticipation.
      - Juckel et al:
        
        Measured ventral striatum activity levels.
        
        Lower levels in controls.
        
        Negative correlation between activity levels & severity of negative symptoms.
    - - Allen et al:
        
        Scanned brains of people experiencing auditory hallucinations.
        
        Compared to control
        
        Lower activation levels in superior temporal gyrus & anterior cingulate gyrus of hallucination group.
  - - - Gottesman: As genetic similarity increase, so does probability of sharing schizophrenia.
    - - Ripke et al:
        
        Genetic make-up of 37000 patients compared to 113000 controls.
        
        108 genetic variations associated with increased risk.
  - - - E.g. Gottesman, Tienari, Ripke.
    - - Drug studies (Curran et al), (Tauscher et al), Lindstroem found chemicals needed to produce dopamine taken up faster in schizophrenic brain.
        
        Some genes in Ripke et al implies other neurotransmitters, e.g. Recent research focuses on glutamate.
- - - - Cheniaux et al study, different results for DSM & ICD.
    - - Buckley et al:
        
        Around 50% schizophrenics diagnosed depression.
        
        47% for substance abuse.
        
        29% PTSD.
        
        OCD for 23%.
        
        Therefore could just be severe depression.
    - - Cheniaux et al
        
        2 psychiatrists diagnose 100 patients with both classification.
        
        One diagnosed 26 with DSM & 44 ICD.
        
        Other diagnosed 13 with DSM & 24 ICD.
- - - - Pharoah et al:
        
        Moderate evidence for reduction of hospital admission.
        
        Overall weak evidence due to inconsistent results & problematic research.
      - Jauhar: 34 CBT studies of schizophrenia, CBT has significant but small effect of symptoms.
      - McMonagle & Sultana: Only 3 studies had patients been randomly allocated to conditions, total 110.
    - - CBT challenges patients core beliefs, may be interfering with freedom of thought.
- - - - E.g. Antipsychotic drugs combined with CBT or family therapy.
  - - - Tienari et al:
        
        Adoptees from 19000 Finnish mothers with schizophrenia.
        
        Followed up.
        
        Adoptive mothers assessed for child-rearing style.
        
        Compared to control without genetic risk.
        
        High levels of criticism & conflict & low empathy in development of schizophrenia, though only for those with genetic risk.
    - - Houston et al: Childhood sexual trauma was vulnerability while cannabis was trigger.
    - - Tarrier et al:
        
        315 patients randomly allocated to groups.
        
        Med + CBT, med + supportive counselling or control (med only).
        
        Combination groups showed lower symptoms.
  - - - Read et al propsed neurodevelopment model in child abuse that can affect brain development, e.g. HPA system can become overactive to make vulnerable to stress.
- - - - May encourage parent blaming.
    - - Stirling et al:
        
        Compared 30 schizophrenics & 18 controls on cognitive tasks, including the Stroop test.
        
        Patients took longer to do.
      - Though doesn't explain origin of cognitions.
    - - Read et al:
        
        46 child abuse & schizophrenia studies.
        
        69% adult women with schizophrenia had history of physical abuse and or sexual abuse.
        
        59% for men.
- - - - 1950s, tablets, syrup or injection.
      - Oral: maximum 1000mg, doses usually maximum 400-800mg
      - Acts as antagonist, blocks dopamine receptors in synapses to reduce activity.
      - Effective sedative, may be related to effect on histamine receptors.
  - - - Remarketed 1980s due to risk of agranulocytosis.
      - Not in injection, daily dose 300-450mg.
      - Same function as chlorpromazine, but also works on serotonin & glutamate receptors.
      - Eases symptoms of depression.
    - - 1990s, tablets, syrup or injection, daily 4-8mg,
      - Works as other drugs, though binds more strongly to dopamine receptors, more effective in small doses.
      - Evidence suggesting fewer side effects.
  - - - Neuroleptic Malignant Syndrome, high temperature, delirium, coma & can be fatal.
    - - Modern understanding of dopamine & psychosis suggests drugs shouldn't work.
    - - Thornley et al:
        
        Data from 13 trials with 1121 participants.
        
        Chlorpromazine reduced symptoms severity.
        
        Data from 3 trials with 512 participants.
        
        Relapse rate lower with chlorpromazine.
      - Meltzer:
        
        More effective than typical & atypical antipsychotics.
        
        Effective in 30-50% cases of failed typical antipsychotics.