Transcript A2 Schizophrenia
SCHIZOPHRENIA
SCHIZOPHRENIA
Clinical characteristics of schizophrenia Issues surrounding classification and diagnosis of schizophrenia, including reliability and validity Biological explanations of schizophrenia e.g. genetics, biochemistry.
Psychological explanations…, e.g. behavioural, cognitive, psychodynamic and socio-cultural Biological therapies for schizophrenia including their evaluation in terms of appropriateness and effectiveness Psychological therapies…, for example behavioural, psychodynamic and cognitive-behavioural, including their evaluation in terms of appropriateness and effectiveness
Deconstructing questions
Outline and evaluate….
Describe and evaluate… Discuss… Critically consider… Compare and contrast Each question has an AO1 component component and an AO2/AO3 e.g. Critically consider two or more biological explanations of schizophrenia.
(25 marks)
Deconstructing questions
All AO1
(a) Outline two psychological explanations of schizophrenia.
(9 marks) (b) To what extent are the two psychological explanations of schizophrenia outlined in (a) supported by research evidence ?
(16 marks)
All AO2/AO3
AO1 = 9, AO2 = 12, AO3 = 4
Deconstructing questions
All AO1
(a) Outline two psychological explanations of schizophrenia.
(9 marks) (b) To what extent are the two psychological explanations of schizophrenia outlined in (a) supported by research evidence ?
(16 marks)
All AO2/AO3
AO1 = 9, AO2/AO3 = 16
Deconstructing questions
1. Outline clinical characteristics of schizophrenia.
(
5 marks
)
2. Explain issues associated with classification and diagnosis of schizophrenia. (
10 marks
) 3. Outline and evaluate one or more explanations of schizophrenia. Refer to research evidence in your answer. (
4 marks
+
6 marks
)
Deconstructing questions
1. Outline clinical characteristics of schizophrenia.
(
125 words
)
2. Explain issues associated with classification and diagnosis of schizophrenia.
(
250 words
)
3. Outline and evaluate one or more explanations of schizophrenia. Refer to research evidence in your answer.
(
100 words + 150 words
)
(a) (b) (c) Symptoms
e.g. thought control, delusions, hallucinations incoherent speech, negative symptoms [125 words] Issues of reliability AO2 = 125 words Issues of validity AO2 = 125 words Evaluation of the explanation(s) [AO2 = 75 WORDS] Outline of explanation(s) of schizophrenia [AO1 = 100 words] Evaluation of the explanation(s) [AO2 = 75 WORDS]
POSITIVE SYMPTOMS
[65 words]
Delusions
Beliefs (e.g. paranoid delusions) that seem real to the schizophrenic but are not real Symptoms that reflect an excess or distortion of normal functions. Diagnosis of schizophrenia requires at least one-month duration of two or more of these
Hallucinations
Bizarre, unreal perceptions of the environment that are usually auditory
Disordered thinking
The feeling that thoughts have been inserted or withdrawn from the mind
NEGATIVE SYMPTOMS
[60 words]
Affective flattening
A reduction in the range and intensity of emotional expression Symptoms that reflect a diminution or loss of normal functions. Patients with mostly negative symptoms are often deemed ‘treatment-resistant’.
Alogia
Poverty of speech thought to reflect slowing or blocked thoughts
Avolition
Reduction of, or inability to initiate and persist in goal directed behaviour
Issues of reliability AO2 = 125 words
ISSUES OF RELIABILITY
Issues of validity AO2 = 125 words
ISSUES OF VALIDITY
What is it?
Bentall et al. (1988) –after comprehensive review of research into the symptoms, prognosis and treatment concluded that schizophrenia was ‘not a useful scientific category’
Why?
Symptoms: Many ‘first-rank’ symptoms of schizophrenia (e.g. delusions, thought disorders) are also found in other disorders e.g. depression and bipolar disorder, making it difficult to separate schizophrenia as a distinct disorder
Why?
Prognosis: Varies with about 20% recovering previous level of functioning, 10% showing significant improvement and 30% some improvement. Remaining 40% never really recover. Demonstrates little predictive validity to a diagnosis of schizophrenia with so much variation in prognosis for the disorder.
Outline of explanation(s) of schizophrenia [AO1 = 100 words]
THE DOPAMINE HYPOTHESIS
Messages from neurons that transmit dopamine fire too easily or too often, leading to symptoms of schizophrenia.
Schizophrenics thought to have abnormally high numbers of D 2 receptors on receiving neurons, leading to more dopamine binding and more neurons firing.
Post-mortems of schizophrenics have shown elevated levels of dopamine and dopamine receptors in the brains of schizophrenics (e.g. Roberts et al., 1996). Amphetamine is a dopamine agonist, flooding synapse with dopamine. Large doses can cause hallucinations and delusions.
Some people with Parkinson’s Disease who take L-dopa to raise dopamine levels develop schizophrenic symptoms (Grilly, 2002).
Evaluation of the explanation(s) [AO2 = 50 WORDS]
THE DOPAMINE HYPOTHESIS
The diathesis-stress model
A problem for the dopamine hypothesis is that psychological factors (e.g. expressed emotion) also influence the development of or recovery from the disorder. This suggests that for those with a biological vulnerability (a diathesis such as high levels of dopamine activity), schizophrenia only develops in the presence of significant stressors in that person’s life
Evaluation of evidence for or against the explanation(s) [AO2/AO3 = 1o0 WORDS]
THE DOPAMINE HYPOTHESIS
Post-mortem studies A problem is
that anti-psychotic drugs that block dopamine may actually increase it as neurons compensate for the sudden deficiency of dopamine
A review of
post-mortem studies (Harack, 1982) found that most of those who showed elevated dopamine levels had received anti-psychotic medication shortly before death
This suggests that
evidence for high levels of dopamine in schizophrenic may not be the cause of the disorder, but a consequence of its treatment
Neuroimaging research
Previous studies have assessed dopamine levels from waste products, but this is far from precise. Development of PET scans has led to more accurate measurement of dopamine levels, yet research using PET scans has failed to provide convincing evidence of altered dopamine activity in brains of individuals with schizophrenia.
Every complex phenomenon can be explained by analyzing the simplest, most basic physical mechanisms that are in operation during the phenomenon.
This is a reductionist explanation because it REDUCES causation to the biochemical level and does not take into account other possible causes of schizophrenia such as the the presence of life stressors. If the disorder was caused solely by malfunctioning dopamine neurons, then using antipsychotic drugs (which reduce dopamine activity in the brain) should be effective for ALL schizophrenics. This is not the case, suggesting that the dopamine explanation alone cannot explain the development of schizophrenia.
EXPLANATION 2: ENLARGED VENTRICLES
Many schizophrenics have enlarged brain ventricles. The ventricles of a person with schizophrenia are about 15% bigger than normal (Torrey, 2002). People who have enlarged ventricles tend to display negative rather than positive symptoms, have greater cognitive disturbances, and poorer responses to traditional antipsychotics (Bornstein et al., 1992).
EXPLANATION 2: ENLARGED VENTRICLES
Research evidence on the importance of enlarged ventricles is far from consistent. A meta-analysis (Copolov and Crook, 2000) of over 90 CT scan studies revealed a substantial overlap between the schizophrenic and control populations.
EXPLANATION 2: ENLARGED VENTRICLES
A possible explanation for why some schizophrenics have enlarged ventricles may be due to the use of antipsychotic medication rather than it being a cause of schizophrenia. A study by Lyon et al. (1981) found that as the dose of medication increased, the density of brain tissue decreased, leading to enlarged ventricles.
Deconstructing questions
AO1 = 4, AO2 = 6 (a) Explain the use of one psychological therapy as applied to the treatment of schizophrenia.
(
10 marks
) (b) Outline and evaluate one or more biological therapies as treatments of schizophrenia.
(
15 marks
) AO1 = 5, AO2/AO3 = 10
Deconstructing questions
AO1 = 4, AO2 = 6 (a) Explain the use of one psychological therapy as applied to the treatment of schizophrenia.
(
4 + 6 marks
) (b) Outline and evaluate one or more biological therapies as treatments of schizophrenia.
(
5 + 10 marks
) AO1 = 5, AO2/AO3 = 10
Deconstructing questions
AO1 = 100, AO2 = 150 words (a) Explain the use of one psychological therapy as applied to the treatment of schizophrenia.
(
4 + 6 marks
) (b) Outline and evaluate one or more biological therapies as treatments of schizophrenia.
(
5 + 10 marks
) AO1 = 125, AO2/AO3 = 250 words
(a) Explain the use of one psychological therapy as applied to the treatment of schizophrenia.
(10 marks) AO1 = 100 words
Cognitive-behavioural therapy (CBT)
Schizophrenics have distorted beliefs which influence their behaviour in maladaptive ways, e.g. delusions are faulty interpretations of events. CBT helps to identify and correct these.
Patients encouraged to trace the origins of symptoms to get a better idea how they might have developed, and to evaluate the contents of their delusions or any inner voices to consider how they might test the validity of their faulty beliefs.
As the learning of maladaptive responses is often the result of distorted thinking or mistakes in assessing cause and effect, the therapist lets the patient develop alternative explanations and coping strategies that are less maladaptive.
(a) Explain the use of one psychological therapy as applied to the treatment of schizophrenia.
(4 + 6 marks) AO2 = 150 words
Evidence from outcome studies
CBT plus medication = greater reduction in positive symptoms than medication alone (Drury et al., 1996) CBT plus medication = less patient dropout and more patient satisfaction than medication alone (Kuipers et al., 1997)
CBT CBT and negative symptoms
CBT works by generating less distressing explanations for negative symptoms rather than eliminating them completely. Negative symptoms (such as inactivity or withdrawal) may be the patient’s way of avoiding making positive symptoms worse.
Who benefits from CBT?
Not everybody who would benefit from CBT is offered the treatment. Kingdon and Kirschen (2006) found many patients denied CBT because they would not ‘fully engage with the therapy’, in particular older patients less likely to receive CBT
(b) Outline and evaluate one or more biological therapies as treatments of schizophrenia.
(5 + 10 marks) AO1 = 125 words
Conventional antipsychotics
These are dopamine antagonists because they bind to dopamine receptors, but don’t stimulate them, instead blocking their action. By reducing stimulation at these receptors, they can eliminate most of the hallucinations and delusions experienced by schizophrenics. Their effectiveness at reducing positive symptoms led to the dopamine hypothesis of schizophrenia.
Atypical antipsychotics
These work by only temporarily occupying the D 2 receptors and then rapidly dissociating to allow normal dopamine transmission. This is thought to be responsible for the lower levels of side effects (such as tardive dyskinesia) found with atypical compared to conventional antipsychotics, which in turn means that patients are more likely to continue with their medication.
(b) Outline and evaluate one or more biological therapies as treatments of schizophrenia.
(15 marks) AO2 = 150 words
Effectiveness
Conventional – relapse rates higher under placebo condition (Davis et al., 1980) Atypical – meta-analysis (Leucht et al., 1999) found superiority over conventional drugs was only ‘moderate’
Motivational deficits
Being prescribed medication may reinforce to the patient that physiologically there is ‘something wrong with them’, thus preventing them from thinking about other possible causes of their stress.
Appropriateness
Conventional – many worrying side effects including tardive dyskinesia (TD) (30% of patients) Atypical – claim of lower levels of TD supported in study by Jeste et al. (1999)
GIVING YOUR AO2
CLOUT
IDENTIFY
Treating schizophrenia with antipsychotic medication may lead to motivational deficits…
JUSTIFY
… because this may reinforce to the patient that physiologically there is ‘something wrong with them’.
SO WHAT?
As a result, this may prevent them from considering other possible causes of their condition, which then makes complete recovery from their symptoms less likely.
(b) Outline and evaluate one or more biological therapies as treatments of schizophrenia.
(5 + 10 marks) AO3 = 100 words
(b) Outline and evaluate one or more biological therapies as treatments of schizophrenia.
(5 + 10 marks) AO3 = 100 words