Schizophrenia AQA Psych

• Schizophrenia is a severe mental illness where contact with reality and insight are impaired, an example of psychosis
• Classification


  The process of organising symptoms into categories based on which symptoms cluster together in sufferers
• Diagnosis


  The assigning of a label of a disorder to a patient
• The ICD-10 (only negative symptoms need to be present) is used worldwide and the DSM-5 (only positive symptoms need to be present) is used in America
• Positive Symptoms


  • Hallucinations
  • Delusions
  • Thought disturbances
• Negative Symptoms


  • Psychomotor disturbances
  • Avolition
  • Disturbances of mood
  • Thought disorders
• Slater & Roth (1969) say that hallucinations are the least important of all the symptoms, as they are not exclusive to schizophrenic people
• Scheff (1966) points out that diagnosis classification labels the individual, and this can have many adverse effects, such as a self-fulfilling prophecy and lower self-esteem
• Reliability


  The level of agreement on the diagnosis by different psychiatrists across time and cultures; stability of diagnosis over time given no change in symptoms
• Jakobsen et al. (2005) tested the reliability of the ICD-10 classification system in diagnosing schizophrenia and obtained a concordance rate of 98%
• Comorbidity


  People who suffer from two or more mental disorders
• Loring and Powell (1988) found that some behavior which was regarded as psychotic in males was not regarded as psychotic in females
• Validity


  The extent to which schizophrenia is a unique syndrome with characteristics, signs and symptoms
• In the USA only 20% of psychiatric patients were classed as having schizophrenia in the 1930s but this rose to 80% in the 1950s, suggesting neither group had a valid definition of schizophrenia
• Heather (1976) found there is only a 50% chance of predicting what treatment a patient will receive based on diagnosis, suggesting that diagnosis is not valid
• David Rosenhan (1973) famous experiment involving Pseudopatients led to 8 normal people being kept in hospital despite behaving normally, suggesting the doctors had no valid method for detecting schizophrenia
• Cochrane (1977) 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
• Genetics


  Family studies find individuals who have schizophrenia and determine whether their biological relatives are similarly affected more often than non-biological relatives
• Identical (monozygotic) and fraternal (dizygotic) twins

  • Identical twins have a 48% risk of getting schizophrenia whereas fraternal twins have a 17% risk rate
  • The higher the degree of genetic relativeness, the higher the risk of getting schizophrenia
• Gottesman (1991) has found that schizophrenia is more common in the biological relatives of a schizophrenic, and that the closer the degree of genetic relatedness, the greater the risk
• Dopamine hypothesis

  Schizophrenia is caused by an excessive amount of the neurotransmitter dopamine, leading to acute episodes and positive symptoms
• Amphetamines increase the amounts of dopamine and can produce behavior similar to paranoid schizophrenia
• Autopsies have found that there are generally a large number of dopamine receptors in schizophrenic patients
• Farde et al. found no difference between schizophrenics' levels of dopamine compared with non-schizophrenics, which is a criticism of the dopamine hypothesis
• An explanation developed, which suggests that it is not excessive dopamine but that fact that there are more dopamine receptors. More receptors lead to more firing and an over production of messages.
• Autopsies have found that there are generally a large number of dopamine receptors (Owen et al., 1987) and there was an increase in the amount of dopamine in the left amygdale (falkai et al. 1988) and increased dopamine in the caudate nucleus and putamen (Owen et al, 1978).
• Is the raised dopamine levels the cause of the schizophrenia, or is it the raised dopamine level the result of schizophrenia?

  It is not clear which comes first
• Farde et al found no difference between schizophrenics' levels of dopamine compared with 'healthy' individuals in 1990.
• Noll (2009) also argues around one third of patients do not respond to drugs which block dopamine so other neurotransmitters may be involved.
• The dopamine hypothesis is biologically deterministic as it suggests that if the individual does have excessive amounts of dopamine then they will develop schizophrenia.
• Neural correlates


  Patterns of structure or activity in the brain that occur in conjunction with schizophrenia
• People with schizophrenia have abnormally large ventricles in the brain. Ventricles are fluid filled cavities (i.e. holes) in the brain that supply nutrients and remove waste. This means that the brains of schizophrenics are lighter than normal. The ventricles of a person with schizophrenia are on average about 15% bigger than normal (Torrey, 2002).
• Research into enlarged ventricles and neurotransmitter levels

  • High reliability as it is carried out in highly controlled environments, using specialist, high tech equipment such as MRI and PET scans
  • These machines take accurate readings of brain regions such as the frontal and pre-frontal cortex, the basil ganglia, the hippocampus and the amygdale
• Suddath et al. (1990) used MRI to obtain pictures of the brain structure of MZ twins in which one twin was schizophrenic. The schizophrenic twin generally had more enlarged ventricles and a reduced anterior hypothalamus. The differences were so large the schizophrenic twins could be easily identified from the brain images in 12 out of 15 pairs.
• The neuroanatomical explanations are biologically deterministic as they suggest that if the individual does have large ventricles then they will develop schizophrenia.
• Family Dysfunction


  Any forms of abnormal processes within a family such as conflict, communication problems, cold parenting, criticism, control and high levels of expressed emotions
• Laing and others rejected the medical / biological explanation of mental disorders. They did not believe that schizophrenia was a disease. They believed that schizophrenia was a result of social pressures from life.
• Double bind theory


  Children who frequently receive contradictory messages from their parents are more likely to develop schizophrenia
• Prolonged exposure to such interactions prevents the development of an internally coherent construction of reality; in the long run, this manifests itself as typically schizophrenic symptoms such as flattening affect, delusions and hallucinations, incoherent thinking and speaking, and in some cases paranoia.
• Expressed Emotion (EE)


  A family communication style that involves criticism, hostility and emotional over-involvement