Schizophrenia Flashcards
(29 cards)
Classification of schizophrenia in ICD and DSM-5
DSM-5: 1 positive symptom
ICD: 2 or more negative symptoms
Rosenhan study
Pseudopatients attempt admission to mental hospitals. Said they heard voices but acted normally. All admitted to hospital and nearly all diagnosed w sz. Spent between 7 and 52 days in hospital
What did Rosenhan’s study show
Reliability of diagnosis is good because there was consistency.
However there is low validity in the diagnosis as none of them actually had sz.
4 positive and negative symptoms
Positive: hallucinations, delusions
Negative: speech poverty, avolition (loss of motivation)
1 strength 2 weaknesses of diagnosis and classification of sz
+ good reliability. Osorio reported excellent reliability for diagnosis in 180 individuals using DSM-5. Pairs of interviewers achieved inter rater reliability of +.97 and test retest of +.92. Diagnosis is consistently applied
- culture bias. Afro Caribean people are 9 times more likely receive a diagnosis than white british ppl. culture bias in diagnosis of patients from different cultural background.
- symptom overlap. both sz and bipolar involve positive and negative symptoms. means sz is hard to distinguish and may not exist as a distinct condition
Gottesman family study findings
48% chance if MZ twin, 9% sibling, 2% aunt.
Candidate genes: Ripke findings
combined genome studies of 37,000 sz with 113,000 controls. Found 108 separate genetic variations associated with risk of sz.
Neural correlates of sz: original dopamine hypothesis
Based on discovery that drugs used to treat sz caused symptoms similar to those in parkinsons, associated w low dopamine. Sz may be result of high dopamine (hyperdopaminergia) in subcortical areas in brain.
Updated dopamine hypothesis
Hypodopaminergia: low dopamine in brains cortex. Low dopamine in prefrontal cortex can explain cognitive problems i.e negative symptoms.
Strength and limitation of genetic explanation for sz
+ research support. Tienari show biological children with parents w sz have heightened risk, even when growing up in adoptive family. Shows people are vulnerable to sz due to genetic makeup.
- environmental influence. Morkved found 67% of ppl w sz and other psychotic disorders had at least 1 childhood trauma, opposed to 38% of matched group with non psychotic mental health issues.
Psychological explanation: schizophrenogenic mother AO1
Reichmann. Her patients spoke of a particular parent. The mother was cold, rejecting, controlling and created family tension. Leads to distrust developing into paranoid delusions and sz.
Psychological explanations: double bind theory
AO1
Bateson. Emphasised role of communication style in family. Child often finds themselves in situations where they feel theyre doing the wrong thing, but receive mixed messages. When they get it wrong, they are punished by withdrawal of love. Leaves them viewing world as confusing and dangerous, and is reflected in disorganised thinking and paranoid delusions
Psychological explanations: expressed emotion
AO1
The level of emotions, particularly negative, expressed to person with sz by family members. e.g verbal criticism, hostility, overinvolvement. Serious source of stress, can trigger onset of sz in someone who is already vulnerable and explain relapses.
Psychological explanations: cognitive: dysfunctional thinking
Sz is characterised by disruption to normal thought processing. Reduced thought processing in ventral striatum is associated with negative symptoms, and reduced info processing in temporal gyri is associated with hallucinations. The lower than usual level on info processing suggests cognition is likely to be impaired.
Psychological explanations: cognitive: Frith metarepresentation dysfunction and central control dysfunction
Metarepresentation: cognitive ability to reflect on thoughts and behaviour. Dysfunction disrupts ability to recognise own thoughts and actions as being our own, explains hallucinations and hearing voices.
Central control: inability to supress automatic thoughts can cause speech poverty e.g each word may trigger associations and person cannot supress automatic response to these.
1 strength 2 weaknesses of family dysfunction explanation
+ support. Read found adults w sz are likely to have insecure attachment, and 59% of men and 69% of women had history of physical/sexual abuse. family dysfunction increases liklehood of sz
- poor evidence base. none to support schizophrenogenic mother and double bind. based on clinical observation, and informal assessment of mother but not systematic evidence.
- parent blaming. socially sensitive to already distressing situation for parents.
1 strength 1 weakness of cognitive explanation
+ research support. Stirling compared performance on cognitive tasks in 30 sz ppl and 30 controls. Tasks included stroop task: sz took twice as long as controls when naming colours instead of word. cognitive processes in ppl w sz are impaired.
- proximinal explanation. explain what is happening now to produce symptoms as opposed to distal explanations that focus on what caused it e.g genes. only provide partial explanation for sz.
3 strengths of dopamine hypothesis
+ Antipsychotic drugs that reduce sz do so by blocking dopamine proves that levels of dopamine alter and change behaviour
+ Research shown that drugs that increase levels of dopamine i.e. amphetamines produce psychotic symptoms - too much dopamine causes sz
+ Low levels of dopamine linked to negative symptoms of sz like avolition - supports hypodopaminergia
Difference between typical and atypical antipsychotics
Typical: First gen of antipsychotics, used since 60s and work as dopamine antagonists e.g chlorpromazine.
Atypical: Developed after typical, target range of neurotransmitters e.g dopamine and serotonin e.g clozapine and risperidone
Overview of typical antipsychotics
- Chlorpromazine. Can be taken by tablets, syrup or injection. Dosage gradually increased to maximum of 400-800mg. Strong association with dopamine hypothesis. Blocks dopamine receptors, reducing action of dopamine. Reduces hallucinations. Syrup absorbed fastest
Overview of atypical antipsychotics
Aim in development was to improve effectiveness and minimise side effects. Range of types, we dont know how some of them work.
Clozapine: used when other treatments failed as there is a high risk of developing arganulocytosis. those on this drug have regular blood tests. Binds to dopamine receptors but also acts on serotonin and glutamate receptors. Believed it improves mood and reduced depression. Risperidone developed to be as effective as clozapine without the serious side effects. Binds to dopamine receptors stronger than clozapine so therefore effective in smaller doses
1 strength 2 weaknesses of drug therapies
+ evidence. Thornley compared effects of chlorpromazine to controls who had sz and recieved placebo. Chlorp was associated with better overall functioning, reduced symptom severity, and reduced relapse rate.
- serious side effects. typical associated with dizziness, weight gain and tardive dyskinesia. Atypical have less side effects however still risks in developing agranulocystosis.
- problems with evidence of effectiveness. Healy argues some successful trials have had their data published multiple times, exagerating positive effects. Also antipsychotics have calming effects making it easy to say they have positive effects, but not the same as reducing severity of psychosis.
CBT in sz treatment
- takes place in 5-20 sessions and aims to challenge irrational thoughts
- make sense of their hallucinations impacting mood. Understanding where symptoms come from can be helpful e.g giving psychological explanations s they dont think the voices are demons.
Family therapy in sz
Psychological treatment
- takes place with families rather than individual clients
- aims to improve quality of communication and interaction between f members and reducing stress that family may contribute
- Pharoah identified range of strategies how families aim to improve functioning of family:
- forming alliance with members
- reducing stress of caring for sz person
- reduction of anger and guilt in members
- improving members beliefs about sz
These work by reducing stress and EE. Reduces liklehood of relapse
