Schizophrenia Flashcards
What is schizophrenia?
Severe mental illness where contact with reality and insight are impaired.
What is used to diagnose sz?
DSM-5
What are positive symptoms?
Additional symptoms beyond those of ordinary existence eg. hallucinations and delusions.
What are negative symptoms?
Loss of usual abilities and experiences eg. speech poverty and avolition.
What is a strength of the diagnosis and and classification?
Reliability, inter rater and test retest. Osorio et al 180 individuals, inter rater +97, test retest +92. Reasonably consistently applied.
What are limitations of the diagnosis and classification?
Low validity -, criterion validity, Cheniaux et al 2 psychiatrists same 100 clients, 68 ICD diagnosed, 39 DSM. So under or over diagnosed.
Comorbidity - sz commonly diagnosed with other conditions eg. about half depressed/substance abuse. May not exist as distinct condition.
State some correlations Gottesman suggested?
mz twins - 48%
siblings - 9%
general population - 1%
What are candidate genes?
Genes associated with higher risks of sz developing
What does polygenic mean?
Number of different genes associated with sz
What did Ripke find about genes?
108 genes involved in sz risk
What does aetiologically heterogenous mean?
Different combinations of factors can lead to the condition.
What is another genetic factor?
Mutations due to radiation, poison or infection
What did the original dopamine hypothesis suggest?
High levels of dopamine in subcortical areas of brain. Can be responsible for speech poverty due to brocas area having excess DA receptors.
What did the updated dopamine hypothesis suggest?
David et al - low DA in brains cortex. eg. low in prefrontal linked to negative symptoms. also looks at origins of abnormal DA function
evaluate genetic explanations
strength - strong evidence, family studies eg gottesman show risk increases with genetic similarity. Adoption studies eg Tienari et al bio children of sz parents heightened risk. Twin study Hilker et al concordance rate 33% mz, 7% dz.
limitation - clear evidence for environment. bio environmental eg birth complications, and thc smoking.. Also psych environmental eg trauma. Morkved et al - 67% sz at least one childhood trauma. genetic factors alone not enough
evaluate neural correlates
strength - support for DA involvement, amphetamines increase DA and worsen symptoms and induce symptoms in people without. antipsychotics reduce DA levels and reduce symptoms.
limitation - glutamate role, post mortem and live scanning studies found raised levels of glutamate. several candidate genes linked to glutamate production.
explain family dysfunction
schizophrenic mother -
Fromm Reichmann, cold rejecting and controlling. leads to paranoid delusions and sz.
double bind theory -
Bateson et al, mixed messages of right and wrong, lead to disorganised thinking and paranoid delusions.
EE - verbal criticism, hostility and emotional overinvolvement. can explain relapsing and triggering individual vulnerable of sz
what is a schizophrenic mother?
(Fromm Reichmann)
Cold and rejecting mother that creates family climate tense and secretive. Leads to distrust leading to paranoid delusions and sz
what is the double bind theory?
(Bateson et al)
mixed messages sent to a child by parents about right and wrong. when get something wrong withdrawal from love by parents. confusion and disorganised thinking.!
evaluate family dysfunction
strength - support, insecure attachment and childhood trauma like abuse. Read et al - adults w sz more likely insecure attachment. 69% women and 59% men history of abuse. Morkved childhood trauma.
limitation - poor evidence base, no support for importance of trad family based theories eg sz mother and double bind. based on observations not systematic evidence. lack scientific methods cant link trauma and sz.
explain cognitive explanations
dysfunctional thinking -
info processing that doesn’t represent reality accurately. reduced thought processing in central striatum creating negative symptoms and reduced processing in cingulate gyri hallucinations.
meta representation dysfunction-
Frith et al, ability to reflect on own thoughts and behaviours. explain hallucinations of hearing voices.
central control dysfunction-
Frith et al, issues with ability to suppress autonomic responses eg. sorry poverty.
what is meta representation?
(Frith et al)
ability to reflect on own thoughts and behaviours. can help to explain hallucinations of hearing voices
evaluate cognitive explanations
strength - evidence, Stirling et al stroop test 30 with sz 30 without. sz took longer over 2x to name font colours. cognitive processes impaired.
limitation - only explain proximal origins, explain what happening now but not what caused. distal explanations like genetics ignored. only partial explanation.
what is a typical antipsychotic?
first sz drugs that work as dopamine antagonists eg. chloropromazine
what are atypical antipsychotics?
second drugs that target DA and serotonin eg. clozapine
evaluate biological therapy
strength - evidence, Thornley et al, reviewed studies 13 trials, chlorpromazine associated with better functioning and reduced symptoms. Meltzer, clozapine more effective as its effective in 30-50% of treatment resistant cases.
limitation - serious side effects, typical dizziness, stiff jaw or tardive dyskinesia. most serious is neuroleptic malignant syndrome can be fatal.
limitation- do not know why they work, tied up with og hypothesis but now not gd explanation. if low DA leads to sz then they shouldn’t work. may not be best treatment.
what comes under psychological therapy for sz?
CBT and family therapy
Explain CBT
cognitive and behavioural techniques. help client make sense of how their irrational cognitions impact their feelings and behaviour. helpful for auditory hallucinations. can help people deal with symptoms.
normalisation = teaching that voice hearing is just extension of ordinary experience of thinking in words.
explain family therapy
aims to improve communication in family and reduce stress of living as a family. Pharoah et al - strategies eg reducing negative emotions like EE and improving families ability to help.
what did Burbacks stages involve?
sharing basic info and emotional support. identifying what to offer. mutual understanding. unhelpful patterns. skill training like stress management. relapse prevention. maintenance for future
evaluate CBT
strength - evidence, Jauhar et al, 34 studies, small but significant effects on positive and negative symptoms. Ponitollo et al, reductions in auditory hallucinations. NICE recommends CBT
limitation - wide range of techniques and symptoms in studies, vary widely. Thomas, diff CBT techniques in studies and people with diff symptoms. overall modest benefits conceal variety of effects of diff CBT techniques. hard to say how effective for each person
evaluate family therapy
strength - evidence, McFarlane, one of most consistently effective treatments. relapse rates reduced by 50-60%. NICE recommends.
strength - benefits everyone, Logan and Barrieclough, families take most care of sz member. wider benefits beyond sz individual
what are token economies?
a form of behavioural modification where desirable behaviours are encouraged by the use of selective reinforcement.
who were Ayllon and Arzin?
trialled token economies in womens sz ward. take eg making bed given tokens which can be swapped for privileges. more tasks completed.
what were the three categories of institutional behaviour tackled by token economies?
(Matson et al)
personal care, condition related behaviours eg apathy and social behaviour
what are the primary and secondary reinforcers?
primary - rewards
secondary - tokens
evaluate token economies
strength - evidence, Glowacki et al, 7 high quality studies showed reduction in negative symptoms and unwanted behaviours.
limitation - ethical issues, professionals given power over patients, imposing own norms on them. restricting pleasures after not doing tasks bad for people suffering already. short term reduction in life quality
limitation - better alternatives, Chiang et al, art therapy high gain and low risk. NICE recommends.
what is the interactions approach?
range of factors to explain behaviour including biological and psychological.
what is the diathesis stress model?
sz result of underlying vulnerability and a trigger which are both necessary for onset of sz.
what was Meehls model of diathesis stress?
diathesis entirely genetic and result of single schizogene.
what is the modern understanding of diathesis?
no single schizogene, factors beyond genetics eg. psychological trauma which alter the development of brain. eg hypothalamic pituitary adrenal system overactive making more vulnerable to later stress.
what is the modern understanding of stress?
anything that risks eg cannabis. increased risk up to 7x. interferes with DA system.
what treatment to interactionists suggest?
biological and psychological, combine antipsychotics and CBT. becoming more common
evaluate the interactionist approach
