- One of the most chronic and disabling of the major mental illness affecting thought processes
- Sufferer is unable to separate reality from unreal experience, such as hallucinations
- Some may only have one psychotic episode, others may have many episodes during a life time, but lead relatively normal lives.
- Two or symptoms need to be present for more than one month, as well as reduced social functioning for a diagnosis to be made.
- Symptoms are divided into positive and negative symptoms, though not all symptoms fit this pattern.
- Positive symptoms are an excess or distortion of normal functions
- Negative symptoms are a decrease or loss of normal functions
- Though Disturbance – Positive Symptoms – e.g. hallucinations and delusions
- Language Impairments – Positive Symptoms – e.g. characteristic. Patients may repeat sounds or use invented words
- Inappropriate of Affect/Violation – Positive Symptoms – e.g. smiling when told bad news
- Blunted and Flat Affect/Violation – Negative Symptoms – e.g. showing little emotion, reduced motivation and interest, and difficulty planning actions
- Psychomotor Disturbances – e.g. catatonia, stereotypy, frenetic activity.
Types I and II
- Distinction is made between Type I Schizophrenia, dominated by positive symptoms and
- Type II Schizophrenia, featuring negative symptoms and has a poorer prognosis.
DSM and ICD
- Diagnostic and Statistical Manual of Mental Disorders is produced by the American psychiatric association
- Contains a list of symptoms for each disorder and guidelines for clinicians who make diagnosis.
- It states that the signs of disturbance should be apparent for at least 6 months
- ICD is the International Classification of Diseases which is produced by the World Health Organisation for both psychical and mental health.
- It states that the signs need to be apparent for one month.
DSM-IV Identifies five main subtypes:
- Paranoid Type – Positive Symptoms – awareness and language are relatively unimpaired
- Disorganised Type – disorganised speech and behaviour
- Catatonic Type – apathy and psychomotor disturbance
- Undifferentiated Type – psychotic symptoms are present, but the criteria for paranoid, disorganised or catatonic types have not been met.
- Residual Type – positive symptoms are present at a low intensity only.
- Concerns the consistency of measurements
- Inter-rater reliability – whether 2 or more clinicians make the same diagnosis when independently assessing a patient. Some error may occur of the same patient gives different information to different clinicians, but some studies provide written material to control this.
- Test-retest reliability – Whether the same clinician gives the same diagnosis when presented the same information on separate occasions
- Current versions of the DSM and ICD are regarded as being considerably more reliable than earlier versions
- DSM is claimed to have higher reliability than ICD because of the degree of specificity in the symptoms identified for each category.
- Beck found 54% agreement between four experienced clinicians when interviewing 153 patients.
- Soderburg reported +.81 reliability with the most recent form of DSM (DSM-IV-TR)
Reliability of Diagnosis of Schizophrenia
- There is evidence both for and against the reliability of a diagnosis of schizophrenia
- Pro – Diagnosis of Schizophrenia has relatively high reliability
- Anti – Read reported that test-retest was as low as +.37 and also described a 1970 study where 194 British and 134 American psychiatrists were asked to provide a diagnosis on the basis of a case description. 69% of the Americans diagnosed Schizophrenia whilst only 2% of the British did so.
- Despite rather low reliability of classification schemes, they are claimed to be useful because they are better than nothing
- Enable research to be conducted linking syndromes to treatments and are better than just making a stab in the dark as to what treatment is likely to be most appropriate
- Concerns the extent to which a diagnosis represents something real
- Reliability – An unreliable diagnosis cannot be valid
- Predictive Validity – If a diagnosis results on a successful treatment then the diagnosis must have been valid. Heather claimed that the same diagnosis had a 50:50 chance of leading to the same or a different treatment, which suggests that diagnosis lack validity.
- Aetiological Validity – Cause of the disorder should be the same for all the patients in that category.
- Descriptive Validity – Patients in different diagnosis categories should differ from each other. It is reduced by comorbidity. Where comorbidity occurs it suggests that the illnesses are not separate categories and therefore not valid
- Cultural Bias – Western Classification systems are culturally biased. Symptoms of a disorder are often cultural specific, therefore members of other cultural groups may be identified as ill when they exhibit behaviours that are normal within their culture, such as hearing voices.
Research into Validity
- Rosenhan demonstrated the poor validity of psychiatric diagnosis.
- Arranged for 8 ‘normal’ people to be examined by admitting doctors in psychiatric hospitals.
- The ‘Pseudo Patients’ were instructed to behave normally, except for reporting that they had heard a voice.
- All except one was admitted as schizophrenic and later released, between 2 and 52 days later as schizophrenics in remission
- It would seem that the context mattered more than the symptoms, though it might be a case of a Type II error – the psychiatrists preferred to call a healthy person sick rather than a sick person healthy.
Research into Validity Continued....
- Rosenhan described his study to the staff at one psychiatric hospital and told them to expect one or more pseudo patients over the next 3 months.
- 193 patients were admitted and all staff were asked to rate the likelihood of whether they were ‘real’.
- In fact, all the patients were genuine, but more than 20% were judged as pseudo patients by one member of staff and 10% were judged so by 2 members of staff.
Validity of diagnosis
- Cultural Bias – Cochrane found that more people of African Caribbean origins were diagnosed as schizophrenic in the UK than whites.
- May be because the disease has a genetic origin, but diagnosis rates for African Caribbean’s are not as high elsewhere in the world
- May be because members of the minority ethnic groups in Britain have more stressful lives
- Diagnosis can be unreliable and inaccurate suggesting they should not be used.
- There are alternatives that don’t require classification, but emphasises listening and analysing each patient’s problems.
- Psychiatric diagnosis can result in labelling, for example a person becomes a ‘schizophrenic’ rather than a person with schizophrenia and this label tends to stick even when the disorder has disappeared.
- Therefore an invalid diagnosis has more serious affects and lifelong implications.
- Many critics would prefer to avoid the use of such labels. Another alternative is to use a system that focuses on the behaviours only.
- Individuals may inherit a gene or genes that cause their schizophrenia
- Research suggests that it is not likely to be one gene and that such genes predispose individuals to develop the disorder, rather than being a certainty.
- Gene Mapping - Sherrington found evidence for a cluster of genes on chromosome 5, which might make an individual susceptible to schizophrenia.
- Subsequent studies have found a range of potential candidates on chromosomes 5, 6, 8, 9, 10, 11, 13, 18, 19 and 22.
- Hahn produced evidence that linked the gene associated with neuregulin with a predisposition for schizophrenia.
- Twin Studies – Gottesman summarised about 40 studies, concluding that the concordance rate is about 48% for MZ twins but only 17% for DZ twins, indicating some environmental influence but a larger genetic component.
Research Evidence Continued....
- Adoption Studies – Tienari reported on the Finnish adoption study, following 155 adopted children whose natural mothers were schizophrenic.
- In adulthood 10.3% of those with schizophrenic mothers had developed schizophrenia compared to only 1.1% of those without schizophrenic mothers.
- Family Studies – Kendler found that first degree relatives of schizophrenics are 18x more likely to be similarly diagnosed.
- In the Copenhagen high-risk study, Parnas followed 207 children who had schizophrenic mothers. At a 27 year follow up, 16% had been diagnosed as schizophrenic compared with 2% in a low risk group.
- High concordance rates in MZ twins may be because they are treated more similarly than DZ twins.
- Family similarities can also be explained by shared environmental influences
- Genetic factors are involved but are not solely responsible. Less than 50% of children where one parent was schizophrenic develop the disorder.
- The diathesis stress model can be used to explain this.
- Rabkin found that schizophrenics do not report significantly more stressful episodes during the months preceding the initial onset of the disorder.
- Research has linked schizophrenia, particularly Type II, to abnormalities in brain structure
- Torrey found enlarged ventricles. This may be the result of having less developed parts of the brain.
- Kim found evidence of smaller frontal lobes and abnormal blood flow to certain areas.
- Post mortem examinations of some schizophrenics show that their brains are 6% lighter and have fewer neurons in the cerebral cortex than normal brains.
- Synder proposed the dopamine hypothesis suggesting schizophrenics have abnormally high levels of dopamine
- This may be due to the fact that schizophrenics have abnormally high numbers of D2 receptors on receiving neurons, leading to more dopamine binding and more neurons firing.
- Original hypothesis was based on evidence that the drugs used to alleviate schizophrenic symptoms, neuroleptics, block dopamine synapses and the release of dopamine.
- Evidence also comes from post-mortem examinations of schizophrenics, which show abnormally high levels of dopamine.
Revises Dopamine Hypothesis
- Original dopamine hypothesis was revised by Davis because it was recognised that dopamine was high in some patients, but not others.
- Also, a new drug, clozapine, is more effective in reducing schizophrenic symptoms, but blocks dopamine activity less.
- The revises hypothesis suggests that: DA high in mesolimbic dopamine system (positive symptoms) – hyperdopaminergia
- DA low in mesocortical dopamine system (negative symptoms) – hypodopaminergia
Revises Dopamine Hypothesis Continued....
- The glutamate hypothesis suggests that it is not the dopamine that is key, but it is the implicated because of its role in glutamate production
- DA receptors inhibit glutamate release and glutamate may be more closely related to root cause.
- Neurological differences may be a cause or effect
- Neurological differences may be genetic or could arise from birth complications. e.g. nurture rather than nature.
- Harrison found that at least some schizophrenics may have experienced brain damage from anoxia at birth
- Torrey suggests a viral cause, which would explain why more schizophrenics were born in late winter
- Neuroleptic drugs block dopamine fairly rapidly, yet they are slow to reduce the symptoms of schizophrenia.
- Healy suggests that drug companies have inappropriately promoted the dopamine hypothesis because it makes money for them.
- Group Splitting Hypothesis – Stevens and Price suggest that some schizophrenic traits serve and adaptive function under certain conditions, such as when social groups become too big and they are much more at risk from predation and have more difficulty with food; a ‘crazy’ individual may act as a leader and enable one subgroup to split off from a main group.
- Origin of Language Theory – Crow proposes that schizophrenia is due to a disruption of language mechanisms. This is supported by the fact that schizophrenics often believe they are hearing voices and/or may use strange language.
- Labelling Theory – Scheff suggests that schizophrenia results from learning that escape to an inner world is rewarding. Individuals who have been labelled as schizophrenic then continue to act in ways that conform to the label. Bizarre behaviours are rewarded with attention and sympathy; this is known as a secondary gain.
- Operant Conditioning – Some psychologists suggest that some children may receive abnormal reinforcements for social behaviours when they are young so they ‘learn’ to behave in bizarre ways to inappropriate stimuli. Therefore, people avoid or respond strangely to the child’s bizarre behaviour, which is further reinforcing and leads eventually to a psychotic state.
- The success of token economies with schizophrenia offers modest support from explanations based on operant conditioning.
- Many symptoms of schizophrenia relate to cognitive malfunction which suggests a cognitive basis for the abnormality
- These malfunctions may be due to psychological abnormalities, such as hallucinations may be produced by brain abnormalities and therefore ‘real’.
- However, other people are not likely to believe someone who reports hallucinations and, therefore, a sufferer may be labelled ‘mad’ and may also start to feel they are persecuted.
Research has found evidence of real hallucinations and other sensory problems in schizophrenics which supports this explanation (Elkins and Cromwell)
Freud proposed that 2 psychological processes were involved in the development of schizophrenia
1. Regression to a pre-ego state – harsh emotional environment leads a person to regress to an infantile state where they may talk and behave like a baby
2. Efforts to re-establish ego control – the effect of regression is for the ego to try to re-take control, which results in other typical schizophrenic symptoms such as auditory hallucinations.
- Been little empirical support for psychodynamic explanations
- Family relations may be an effect. Oltmanns found that parents of schizophrenics did behave differently from parents of other kinds of mental patients.
- Studies of schizophrenic families usually occur after the onset of the disease and, therefore, the dynamics have probably been altered by the stresses of having an ill son/daughter.
Social Cultural Explanations
- Double bind theory – Bateson proposed that schizophrenia is a learned response to mutually exclusive demands being made on a child and also conflicting messages.
- Prolonged exposure results in a child developing their own internally consistent construction of reality
- R.D. Laing regarded schizophrenia as a sane response to a disordered environment.
Social Cultural Explanations Continued....
- Expressed Emotion – The extent to which a family communicates in a critical, hostile and over emotional way. It has been found to be particularly significant as a variable that prevents recovery’ schizophrenics in high expressed emotion families have been found to be less likely to recover.
- Vaughn and Leff found 51% relapse in schizophrenics returning to high expressed emotion homes compares with the 13% relapse for those returning to low expressed emotion homes.
- Social Causation Hypothesis – Members of lower social classes have more stressful lives, and this makes them more vulnerable to schizophrenia.
Social Cultural Explanations Continued....
- However, it may be that developing schizophrenia leads to reduced social status.
- Turner and Wagonfeld found that the fathers of schizophrenics tended to belong to the lower social classes.
- Genetic evidence shows that any account must include biological factors
- Family abnormalities may be a reasonable response to a child with brain damage.
- If the family is at fault, all children should develop the disorder. This suggests that only vulnerable individuals are affected, or those who are made scapegoats.
- Importance of expressed emotion is supported by an adoption study, which showed that children who natural mothers had schizophrenia were likely to develop the disorder than their ‘normal’ adoptive siblings.
- A difference only emerged when the adopted family was rated as disturbed, showing an interaction between genetic vulnerability and environmental stressors
- Environmental factors may be more important in understanding the course rather than the cause of schizophrenia.
- Anti-psychotic drugs are used to treat psychotic illness, such as schizophrenia
- Typical anti-psychotics – e.g. chlorpromazine, are used to treat the positive symptoms of schizophrenia, such as hallucinations. They bind to dopamine receptors at the end of neurons and, therefore block dopamine action, reducing the positive symptoms.
- Atypical anti-psychotics – e.g. clozapine, treat negative symptoms of schizophrenia as well as positive symptoms. They act in the serotonin system as well as the dopamine system by temporarily occupying receptor sites and then allowing normal transmission. May explain why side effects are less severe than when typical anti-psychotics are used.
Appropriateness and Effectiveness
- Conventional anti psychotics have a range of serious side effects, such as extra pyramidal effects – where patients develop movements disorders typical of patients with Parkinson’s disease.
- Serious side effects with the newer atypical anti psychotics, for example clozapine is linked with agranulocytosis, a potentially life threatening drop in the number of white blood cells.
- Davis looked at over 100 studies comparing anti psychotic drugs with placebo treatment and found that the drugs came out as more effective in the vast majority of the studies.
- More than 70% of patients treated with conventional anti psychotics were much improved after 6 weeks, compared with fewer than 25% of patients treated with a placebo only.
Appropriateness and Effectiveness Continued....
- Studies comparing conventional anti psychotics with the newer anti psychotics suggest that the former can be just as effective.
- CATIE study involving 1400 patients, found that the conventional anti psychotic drug, perphenazine, was just as effective as the newer atypical drugs, and no more likely to cause side effects.
- Tharyan and Adams report that ECT remains a common treatment option for people with schizophrenia.
- Reviewed 26 studies and concluded that courses of ECT resulted, in the short term, in better overall improvement in schizophrenics than the use of a placebo.
- However, drug therapies had greater success than ECT alone; anti psychotic drugs plus ECT produced the best outcomes.
- Institutionalised patients are given tokens when they engage in pre-defined correct/socially desirable behaviours.
- The tokens can be exchanged for food or privileges.
- They act as secondary reinforcers, whereas food and privileges are primary reinforces.
- System enables patients to cope better when living independently and may focus particularly on negative symptoms, such as poor motivation and social withdrawal.
Appropriateness and Effectiveness
- Allyon and Azrin used TE to control the behaviour of 45 chronic schizophrenics who had been institutionalised for an average of 16 years.
- They were given tokens for making their beds or combing their hair. The number of chores the patients performed each day increased from about 5 to over 40
- Drawback to this therapy is that it is often fails to transfer to life outside the institution.
Appropriateness and Effectiveness Continued....
- McMonagle and Sultana reviewed several studies and found low support for maintenance of behaviours beyond the treatment programme. However, Woods found fundamental long-term effects
- The effectiveness of tokens may be due to other factors, such as being positively reinforcing from the nursing staff, who feel they are making positive gains and therefore, are stimulated to persist. They also help to structure the situation and ensure consistent rewards.
- Spotnitz pioneered the use of psychoanalysis with schizophrenic patients.
- He believed that treatment needed to focus on redirecting aggression outwards rather than being inward-focused self-hate, which was at the root of serious mental disorders like schizophrenia
- Spotnitz is credited with founding modern psychoanalysis.
Cognitive Behavioural Therapy
- CBT is recommended treatment for people with schizophrenia.
- This approach helps to link the person’s feelings and patterns of thinking that underpin distress.
Appropriateness and Effectiveness
- Sensky compared CBT with a ‘non specific befriending control intervention’
- CBT was effective in treating negative symptoms and positive symptoms that were resistant to standard anti psychotic drugs, with a sustained effect over 9 months later
- However, Jones reviewed 30 studies of CBT and found fairly minimal evidence of effectiveness when treating schizophrenia
Role of Community Care
- The advert of drug therapies has meant many mental patients can be cared for in the community where they receive a mixture of care from mental health teams as well as structured psychotherapy.