schiz ao3

• Dopamine hypothesis


  Original dopamine hypothesis
• Original dopamine hypothesis


  • Evidence: Amphetamines increase amounts of dopamine
  • Large doses of amphetamine given to people with no history of psychological disorders produce behavior which is very similar to paranoid schizophrenia
  • Small doses given to people already suffering from schizophrenia tend to worsen their symptoms
• Second explanation support


  • Autopsies/post mortem have found that there are generally a large number of dopamine receptors in people with schizophrenia
• Parkinson's sufferers treated with L-Dopa


  Unwanted side effect was the development of schizophrenic like symptoms
• This supports the dopamine hypothesis as it suggests that high levels of dopamine may lead to the onset of Schizophrenia
• Noll challenges the dopamine hypothesis
• Challenges to dopamine hypothesis

  • Antipsychotic medications, which 'normalise' levels of dopamine in the brain do not work for two thirds of patients
  • Some people experience hallucinations and delusions despite levels of dopamine being normal
  • Suggests that dopamine is not the sole cause of positive symptoms
  • Suggests that other neurotransmitter systems, independent of dopamine may lead to Schizophrenia
• The dopamine hypothesis does not account for freewill
• Classification and diagnosis


  Allows doctors to communicate more effectively about a patient and use similar terminology when discussing them
• Classification and diagnosis


  Allows doctors to predict the outcome of the disorder and suggest related treatment to help the patient
• Cheniaux et al. had two psychiatrists independently diagnose 100 patients using ICD-10 and DSM-5


  One psychiatrist diagnosed 26 with schizophrenia using DSM-5 and 44 using ICD-10, the second psychiatrist diagnosed 13 with schizophrenia using DSM-5 and 24 using ICD-10
• This shows the diagnosis of schizophrenia is unreliable as its not consistent
• This also shows that there is a lack of validity
• Bizarre delusion


  How bizarre is bizarre? This is not properly defined and so clinicians often use their own experience to classify a delusion as bizarre and so this varies between clinicians
• Buckley et al. found that around half the patients with a diagnosis of schizophrenia also have a diagnosis of depression or substance abuse
• This questions whether we are actually measuring schizophrenia or rather the symptoms of depression and substance abuse
• Because of this, the validity and reliability of the diagnosis is reduced
• An outcome of wrongly diagnosing schizophrenia is that the patient may receive medication with serious side-effects that they do not need
• Loring and Powell found that some behavior which was regarded as psychotic in males was not regarded as psychotic in females
• Cotton et al. found that women typically have a superior level of functioning to men (especially interpersonal) and so may have escaped diagnosis
• Cochrane reported that the incidence of schizophrenia in the West Indies and the UK is 1 %, but that people of Afro-Caribbean origin are seven times more likely to be diagnosed as schizophrenic when living in the UK
• This suggests that there's a cultural bias which leads psychiatrists to overdiagnose schizophrenia in the black population
• Interactionist approach


  Genetic factors and family related stress leads to the onset of schizophrenia
• Diathesis stress model


  • High levels of criticism and conflict and low levels of empathy was implicated in the development of schizophrenia in children with a high genetic risk but had no effect on children with a low genetic risk
• Tarrier et al study


  1. Randomly allocated participants to a control group, medication + CBT or medication and supportive counselling group

  2. The combination groups showed lower symptom levels then the control group
• The interactionist explanation and approach to treatment is more effective than the use of single treatments
• Anderson et al study

  1. Relapse rate of almost 40% when patients had drugs only

  2. Relapse rate of only 20% when Family Therapy or Social Skills training were used

  3. Relapse rate of less than 5% when both were used together with the medication
• Research by Romans-Clarkson et al 1990 found no urban rural difference in mental health among women in New Zealand which suggests urbanisation does not act as a trigger for Schizophrenia
• Varerse et al study


  • Children who experienced severe trauma before the age of 16 were 3 times more likely to develop schizophrenia in later life compared to the general population
  • Relationship between the level of trauma and the likelihood of developing schizophrenia with those severely traumatised as children being at greater risk
• The diathesis stress model that stress acts as a trigger and contributes to the onset of Schizophrenia
• Token economy (practical advantages)

  • Patients becoming more independent and active
  • Nurses' increased respect for the patients
  • Patients becoming even more motivated and developing positive self-esteem
  • Helps with institutionalisation
  • Creates a healthier, safe and stable environment
  • Reduces staff and patient injuries, decreasing staff absenteeism and emergency incident levels
• Ayllon and Azrin study


  • Used a token economy on a ward of female patients with schizophrenia
  • Patients were given plastic tokens, each embossed with the words 'one gift' for behaviours such as making their beds
  • Tokens were later exchanged for rewards such as being able to watch a film
  • Use of a token economy increased dramatically the number of desirable behaviours the patients performed each day
• Any positive effects of the treatment are short-lived
• The treatment does not appear to work long-term as the desirable behaviour becomes dependent on reinforcement
• Upon release into the community, reinforcement ends leading to high re-admittance rates
• Without the professionals there to constantly reinforce the behaviour of people with schizophrenia, they are not able to engage in the target behaviours outside of the hospital setting
• Token economies do not work outside of the hospital
• Ethical issues with token economies

  • Privileges and rewards become more available to patients with mild symptoms and less so for those with more severe symptoms of schizophrenia
  • Most severely ill patients suffer discrimination
  • Clinicians exercise control over important primary reinforcers such as food or privacy which is unethical
• The token economy is seen to be inappropriate and this has reduced the use of token economies in the psychiatric system
• When compared with antipsychotic medication alone

  CBTp was effective in reducing rehospitalisation rates up to 18 months following the end of treatment