Schizophrenia (paper 3) Flashcards
What are the two major systems for classification of the mental disorder? What’s the difference in how they diagnose?
ICD-10
DSM-5
In DSM-5 system 1 of so called positive symptoms must be present for diagnosis whereas 2 or more negative sufficient under ICD
Both have dropped subtypes bc tended to be inconsistent (eg/someone with diagnosis of paranoid schizophrenia wouldn’t necessarily show same symptoms years later
Explain the dopamine hypothesis in relation to schizophrenia
(biological appraoch)
neurotransmitters appear to work diff in brain with schizo
DOPAMINE HYPOTHESIS
- dopamine particularly believed to be inv in important in functioning of several brain systems that may be implicated in symptoms of schizo
- hyperdopaminergia in subcortex
(original version of DH focused on possible role of high levels of dopamine in subcortex, eg/ excess of dopamine receptors in Brocas area (speech production) associated with poverty of speech and/or experience of auditory hallucinations) - hypodopaminergia in cortex
(recent versions of DH focused on abnormal dopamine systems in brains cortex, eg/ Goldman-Rakic et al identified role for low levels of dopamine in prefrontal cortex (thinking & decision making) in negative symptoms of schizo - BOTH explanations may be correct, high&low levels in diff regions of brain lead to schizo
What is hypERdopaminergia in relation to the dopmaine hypothesis?
original version of DH
- focused on possible role of high levels of dopamine in subcortex, eg/ excess of dopamine receptors in Brocas area (speech production) associated with poverty of speech and/or experience of auditory hallucinations)
- BOTH explanations may be correct, high&low levels in diff regions of brain lead to schizo
Outline 2 limitations of the dopmaine hypothesis in explainging schizophrenia
- Evidence to suggest it doesn’t provide full explanation
Some genes identified in Ripke et al study code for production of other neurotransmitters so it appears although dopamine likely to be important factor, so are other factors
Evidence of dopamine is mixed at best - Correlation causation problem-does the unusual activity in brain regions cause symptom? There’s other explanation
Correlation between activity levels in VS & negative symptoms of schizo (maybe something wrong in VS), but just as possible negative symptoms themselves=less info passes through striatum resulting in reduced activity/3rd possibility=another factor influences negative symptoms and VS activity
Existence of neural correlates tells relatively little in themselves
The psychological approach focuses on the psychological envrio and abnormal functioning in cognition
What 2 parts are included in the psychological explanation of schizophrenia?
1 FAMILY DYSFUNCTION (link schizo to childhood&adult experiences of living in dysfunctional family)
- schizophrenogenic mother
- double bind theory
- expressed emotion
2 COGNITIVE EXPLANATION (focused on role of mental processes-schizo is characterised by disruption to thought processing eg/seen reduced processing in VS=reduced processing of info)
- 2 kinds of dysfunctional thought processing that could underlie some symptoms:
Metarepresentation
Central Control
The psychological approach focuses on the psychological envrio and abnormal functioning in cognition
Give 2 advantages
+ Evidence supporting family dysfunction=risk factor (diff family relationships in childhood=associated with increased risk in adulthood)
Read et al reviewed 46 child abuse studies & schizo & concluded 69% women in-patients had history of abuse, for men=59%, adults with insecure attachments to primary carer also=more likely
Thus large body of evidence linking family dysfunction & schizo
(C/A) Evidence shares weakness as info of childhood gathered after symptoms develop so patients may have distorted recall of childhood experiences=validity questioned=results not consistent
+ Strong support for idea infos processed diff. in mind of schizo
Stirling et al compared 30 people with schizo to 18 controls on range of cognitive tasks including stroop test, in line with Friths theory, schizo patients took 2x longer to name ink colours (not say word of colour) than control
(E/C/A) cognitive theories able to explain proximal causes of schizo eg/causes of current symptoms but not distal causes eg/origins f condtion
What are the biological therap
ANTIPSYCHOTICS
-taken as tablets/syrup/injection every 2-4 weeks (if at risk of failing to take medication regularly)
May be short/long-term (some can take for short then stop course without return of symptoms, others would face reoccurrence so require them for life)
Divided into typical (traditional) or atypical (newer) drugs
1 TYPICAL ANTIPSYCHOTICS
-chlorpromazine
2 ATYPICAL ANTIPSYCHOTICS (newer)
- Clozapine
- Risperidone
How do antagonists work?
Are chemicals which reduce action of neurotransmitter
As a biological therapy what is the typical antipsychotic used?
Chlorpromazine
- taken as tablets/syrup/injection (orally=1000mg max but initial=much smaller&for most gradually increased to 400-800mg, typical prescribed doses declined over last 50 years)
Strong correlation to dopamine hypothesis=act as antagonists in dopamine system so block dopamine receptors in synapses of brain, reducing action of dopamine (initially dopamine levels build up but then production reduced)=according to dopamine hypothesis this dopamine antagonist effect normalises neurotransmission in key areas of brain, reducing symptoms eg/hallucinations
Is an effective sedative (related to effect on histamine receptors but not fully understood how =sedation) so often used to calm those with schizo&other conditions-done when first admitted to hospital&very anxious (syrup absorbed fastest so tends to be used for sedative properties)
As a biological therapy what is are the atypical antipsychotic used?
Clozapine (withdrawn for while following deaths due to blood condition but remarketed as treatment for when all else failed after being found to be more effective than others, today have regular blood tests ensuring not developing condition)
Not available as injection due to potentially fatal side effects, daily dose lower than chlorpromazine, typically 300-450mg a day but binds to receptors in same way but additionally acts on serotonin and glutamate receptors believed to improve mood,anxiety&depression=may improve cognitive functioning, mood enhancing effect=sometimes prescribed when high risk of suicide (important as 30-50% patients attempt suicide at some point)
Risperidone=more recently developed, developed in attempt of being as effective as clozapine but without its serious side effects
- taken as tablets/syrup/injection lasting 2 weeks, initial dose=small, then built to typical daily dose of 4-8mg max 12mg
- binds to dopamine&serotnin receptors but more strongly to dopamine than clozapine so much more effective in smaller doses than most, some evidence suggesting leads to fewer side effects than is typical
Give 1 advantage of the biological therapies for schizophrenia (DRUGS)
TYPICAL ANTIPSYCHOTICS
+ Large body of evidence supporting antipsychotics=least moderately effective in tackling symptoms
(TYPICAL) Thornley et al reviewed studies comparing effects of chlorpromazine to control conditions in which patients received placebo so experiences identical except for presence of chlorpromazine in medication-data showed chlorpromazine associated with better overall functioning&reduced symptom severity&showed relapse rate lower when taken
In general are reasonably effective
What are the 3 psychological therapies for schizophrenia?
1 CBT (commonly used for schizo)
2 FAMILY THERAPY (with family rather than individual aiming to improve quality of communication&interaction between members)
3 TOKEN ECONOMIES
As 1 psychological therapy, outline the aims of CBT, how it helps and include a case example, include explanation of effectiveness
- usually 5-20 sessions as groups or individual basis with aim to help identify irrational thoughts & trying to change them (may involve argument/discussion of how, likely beliefs are true & consideration of other less threatening possibilities=doesn’t get rid of symptoms but helps so better able to cope with them)
- helped to make sense of delusions&hallucinations impacting feelings & behaviour (just understanding where symptoms come from=hugely helpful for some eg/if hears voices, believing they’re demons, will naturally be afraid, offering explanation for existence can help reduce this anxiety-delusions challenged so learn beliefs aren’t based on reality)
- Turkington et al described example of CBT used to challenge where paranoid patients’ delusions come from
PATIENT: mafia are observing & deciding how to kill me
THERAPIST: you’re obviously frightened….must be good reason for this
PATIENT: do you think is mafia?
THERAPIST: its possibility but could be other explanations, how do you know its mafia?
As 1 psychological therapy, outline the aims of family therapy, how it helps and include a case example, include explanation of effectiveness
- with family rather than individual aiming to improve quality of communication&interaction between members
- range of therapies eg/keeping with double bind&schizophrenogenic mother, therapists see family as root cause / nowadays most=more concerned with reducing stress within family contributing to risk of relapse, particularly looks at reducing levels of EE
- Pharoah et al identified range of strategies by which family therapists aim to improve functioning of family with member experiencing schizo eg/improve ability of family to anticipate&solve problems, reduction of anger & guilt in members, helping achieve balance of caring & maintain own life = suggests these work by reducing levels of stress & EE whilst increasing chances of people complying to medication, this combo tends to=reduced likelihood of relapse & re-admission to hospital
As 1 psychological therapy, outline the aims of token systems, how it helps and include a case example, include explanation of effectiveness
- reward systems used to mange behaviour particularly those developed patterns of maladaptive behaviour through spending long periods in psychiatric hospitals aka institutionalised, in these circumstances=common for bad hygiene/remain in pjs all day, modifying the bad habits doesn’t cure schizo but improves quality of life & more likely to be able to live outside hospital setting
- idea=TOKENS eg/coloured discs, given immediately when desirable behaviour is carried out thats been targeted for reinforcement eg/getting dressed in morning according to patients individual behaviour issues-immediacy of reward=important to prevent “delay discounting”=reduced effect of delayed reward
- REWARDS=despite token=no value in selves, can be swapped for more tangible rewards (therapy based on operant conditioning, tokens=secondary reinforcers bc only have value once patient learns they can be used to obtain rewards which maybe in form of sweets/magazines/services eg/have room cleaned/walk outside hospital)
- review of evidence of token economies found only 3 studies where people with schizo randomly allocated to conditions with total of only 110 patients (random allocation=important in controlling extraneous variables)=only 1/3 showed improvement in symptoms&none yielded useful info about behaviour change
