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 and an AO2/AO3
component
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
Outline of
explanation(s) of
schizophrenia
[AO1 = 100 words]
Evaluation of the
explanation(s)
[AO2 = 75 WORDS]
Evaluation of the
explanation(s)
[AO2 = 75 WORDS]
POSITIVE SYMPTOMS
[65 words]
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
Delusions
Beliefs (e.g. paranoid
delusions) that seem real
to the schizophrenic but
are not real
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]
Symptoms that reflect a
diminution or loss of normal
functions. Patients with mostly
negative symptoms are often
deemed ‘treatment-resistant’.
Affective flattening
A reduction in the range
and intensity of
emotional expression
Avolition
Reduction of, or inability to
initiate and persist in goaldirected behaviour
Alogia
Poverty of speech
thought to reflect slowing
or blocked thoughts
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 D2 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 and negative symptoms
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 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.
CBT
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
Atypical 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.
These work by only temporarily occupying
the D2 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
Motivational deficits
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’
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