schizophrenia Flashcards
what is schizophrenia
-type of psychosis in which cognition and emotions are so impaired that contact is lost with reality
positive symptoms of schizophrenia
- hallucinations
- delusions
- disorganised speech
- grossly disorganised or catatonic behaviour
what is a positive symtom
an excess or distortion of normal functions
negative symptoms of schizophrenia
- speech poverty (alogia)
- avolition
- affective flattening
- anhedonia
what is a negative symptom
reduction or limitation of normal function
hallucinations - explanation or types
-bizarre, unreal perceptions of the environment that are not present
-can be auditory, visual, olfactory (smell) or tactile
delusions - explanation and types
-bizarre, false beliefs that seem real to the person
-can be paranoid, delusions of grandeur or delusions of reference
disorganised speech - explanation
-problems organising their own thoughts eg. slipping from one topic to another or being so incoherent that their speech sounds like gibberish (word salad)
grossly disorganised behaviour - explanation
-inability or lack of motivation to initiate a task or complete it once its started, leading to difficulties in daily living eg. decreased interest in personal hygiene or dressing in bizarre ways like wearing heavy clothes in summer
catatonic behaviours - explanation
-reduced reaction to the immediate environment
-rigid (often bizarre) postures
-aimless motor activity
speech poverty (alogia) - explanation
-lessening of speech fluency and productivity
-difficulty spontaneously producing words and less complex syntax
avolition - explanation
-reduction of interests and desires
-inability to initiate and persist in goal-directed behaviour (eg. sitting in house for hours doing nothing)
affective flattening - explanation
-fewer body and facial movements
-reduction in range and intensity of emotional expression, voice tone, eye contact and body language
anhedonia - explanation
-loss of interest in pleasure or lack of reactivity to normally pleasurable stimuli
-physical anhedonia - inability to react to physical pleasure
-social anhedonia - inability to experience pleasure from interpersonal situations
reliability of diagnosis definition
refers to the repeatability of diagnosis as a clinician must be able to reach the same conclusions at 2 different points in time (test-retest) or 2 different clinicians must be able to reach the same conclusions (inter-rater reliabilility)
validity of diagnosis definition
refers to whether sz is a unique, distinct syndrome with characteristics, signs and symptoms, and the extent to which we are measuring what we claim to measure
issues w reliability in diagnosis - cultural differences
-cultural differences - copeland - gave british and us psychiatrists description of same patient and 69% of us psychiatrists diagnosed sz, whereas only 2% of british ones did - diff classification methods
issues w reliability in diagnosis - rosenhan study
-had 8 confederates go to 12 diff psych hospitals reporting hearing a voice say words.
-once on the ward had them stop pretending to have symptoms and write observations - patients only discharged when they could convince staff they were sane.
-all patients admitted, despite not having enough symptoms to normally receive a diagnosis, and normal writing behaviour was interpreted as pathological
issues w validity in diagnosis - gender bias
-longenecker - found men have been diagnosed more than women, possibly due to women typically functioning better, having better family relationships and being more likely to work
issues w validity in diagnosis - symptom overlap
-ellason and ross - found patients w DID tend to have more sz symptoms that patients diagnosed w sz
issues w validity in diagnosis - comorbidity
-having 2 or more conditions at the same time
-buckley et al - estimated that co-morbid depression occurs in 50% of all patients and 47% have lifetime diagnosis of co-morbid substance abuse
-swets et al - found 12% of patients have comorbid OCD
genetic explanation - family studies
-gottesman and shields - found children w 2 sz parents had concordance rate of 46% and children w 1 sz parent had rate of 13%
-suggests closer the relative w sz, the greater risk of also developing sz
genetic explanation - adoption studies
-tienari et al - found 6.7% adoptees w a sz bio mother were also diagnosed, compared to 2% of adoptees w non-sz mother
genetic explanation - twin studies
-joseph - found MZ twins had concordance rate of 40%, compared to 7% for DZ twins
limitations of genetic explanations
-reductionist - no 100% concordance rate for MZ
-MZ twins encounter more similar environments and are treated more similarly than DZ twins
bio explanations - dopamine hypothesis
-excess of dopamine in the MESOLIMBIC pathway is associated w positive symptoms
-szs thought to have abnormally high no of D2 receptors, resulting in more dopamine binding
-revised dopamine hypothesis: negative symptoms are a result of deficit of dopamine in the MESOCORTICAL pathway
strengths of dopamine hypothesis
-research support - normal ppl given amphetamines (dopamine inducing drugs) experience hallucinations and delusions
-research support - leucht et al - meta-analysis of studies and found all antipsychotic drugs tested were significantly more effective than a placebo in reducing SZ symptoms
limitation of dopamine hypothesis
-research against - noll - found antipsychotics dont alleviate positive symptoms in 1/3 of ppl and found that some ppl experience hallucinations and delusions when their dopamine levels are normal, so the dopamine hypothesis cant explain these people’s symptoms
psychological explanations - family dysfunction - double bind theory
-bateson et al
-suggests children who frequently receive contradictory messages from their parents are more likely to develop SZ
-leads to child fearing doing the wrong thing, when they dont know what the wrong thing to do is, leading to them having an understanding of the world that is dangerous and confusing
-leads to symptoms such as disorganised thinking and paranoid delusions
psychological explanations - family dysfunction - expressed emotion
-EE is a family communication style where there is:
1. verbal criticism of the patient
2. hostility or rejection towards the patient
3. emotional over-involvement in the life of the patient
-increases relapse rates by 4x
-suggests ppl w sz have lower tolerance for intense emotional comments and interactions, leading to stress beyond their already impaired coping mechanisms, leading to a sz episode.
strengths of family dysfunction (psych explanations)
-research support - tienari et al - found adopted children w sz bio parents only more likely to also develop sz if the adopted family was classified as disturbed
-research support - read et al - found 69% of ppts w sz experienced physical/sexual abuse in childhood
limitation of family dysfunction (psych explanation)
-led to parent blaming - causes more stress for already traumatised parents and can lead to distance between parent and sz child that can increase likelihood of relapse without support of their parent
psychological explanations - cognitive explanations - dysfunction in metarepresentation
-frith et al
-disrupted ability to recognise our own actions and thoughts as being carried out by ourselves, rather than someone else, explaining hallucinations of voices and delusions of thought insertion
psychological explanations - cognitive explanations - dysfunction in central control
-frith et al
-inability to suppress automatic thoughts and speech triggered by other thoughts eg. sufferers tend to experience derailment of thought and speech because each word triggers associations and the patient cannot suppress automatic responses to these.
strengths of cognitive explanations (psych explanation)
-research support - sarin and wallice - found evidence of pos symptoms having origin in faulty cognition eg. hallucinating individuals tend to have impaired self-monitoring and patients w negative symptoms had low expectations for success and pleasure
-success of CBTp - found consistent evidence that CBT is more effective than drugs in reducing symptom severity and improving social functioning
limitation of cognitive explanations (psych explanation)
-reductionist - addresses cognitive impairment, but fails to explain other aspects such as neurochemical changes
drug treatments - typical antipsychotics
-only treats positive symptoms
-bind to D2 receptors in the mesolimbic pathway and block them, so dopamine stimulation is reduced, reducing positive symptoms
-however, also block dopamine receptors in other parts of the brain, causing extrapyramidal side effects (eg. tremors and stiffness)
drug treatments - atypical antipsychotics
-treats positive AND negative symptoms
-bind to and block D2 receptors for a short amount of time (rapid dissociation)
-ALSO blocks serotonin receptors (reducing negative symptoms - improving mood, cognitive functions and reducing depression and anxiety)
-dont have extrapyramidal side effects but do have some fatal side effects so patients need to be monitored while taking them
strengths of drug treatments
-research support - leucht et al - meta-analysis - some patients taken off antipsychotic and given placebo - 64% of those given placebo relapsed, compared to 27% of those who continued antipsychotics
-first method of treatment - given in initial stages of episode to stabilise patient so other forms of treatment can be given
-cheap to produce and readily available so available to wider range of people than therapies
limitations of drug treatments
-side effects - typical antipsychotics have extrapyramidal side effects that 1/2 of patients experience, and atypical ones have fatal side effects so patients need to be monitored while taking them
-Noll - found antipsychotics dont work in 1/3 of ppl
cognitive behavioural therapy (CBTp) - explanation (not method)
-used to treat residual symptoms to improve general functioning and make patients better able to cope with these symptoms
-works on the assumption that people often have distorted beliefs that influence their feelings and behaviours in destructive ways.
method of CBTp - 6 steps
- assessment - describing symptoms, set goals for therapy
- engagement - therapist empathises
- ABC - patient gives explanation of activating events that appear to cause their emotional and behavioural consequences and then rationalises and disputes their beliefs that are the actual cause of the consequences.
- normalisation - helps patient realise many people experience similar symptoms, reducing isolation
- critical collaborative analysis - gentle questioning to help patient recognise negative thoughts and test faulty beliefs
- developing alternative explanations
strength of CBTp
-research support - NICE - effective in reducing rehospitalisation rates up to 18 months after the end of treatment. also reduces symptom severity
limitations of CBTp
-lack of availability - requires trained therapist and time consuming
-requires motivation - negative symptoms often cause lack of motivation so patient may not be able to engage fully, reducing effectiveness
-effectiveness depends on stage of disorder - patients need to be stabilised by drug treatments as they may not be mentally well enough in initial stages to have their delusions challenged.
family therapy treatment - explanation
-form of therapy carried out with the members of a patients family to:
1. educate relatives abt SZ
2. improved family communication and reduce emotional climate
3. teach patients and carers more effective stress management techniques
strengths of family therapy treatment
-research support - Pharoh et al - found FT improved patients compliance w medication and a reduction in relapse during and after treatment
-research support - garety et al - estimated relapse rates were 25% for those who receive FT and 50% for those who dont
-economic benefit - highly cost effective due to reduced relapse rates
-impact on family members - lobban - found 60% of family members reported feeling better able to cope w supporting their relative
token economy treatment - explanation
-desirable behaviours encouraged by positive reinforcement through rewards
-clinicians set target behaviours eg. brushing hair, taking medication etc
-tokens are awarded when target behaviours are engaged with, which can then be exchanged for rewards.
strength of token economy treatment
-research support - allyon and azrin - used token economy in a ward of females w SZ and found TE dramatically increased number of desirable behaviours shown
limitations of token economy treatment
-short-term - only works while inside institutions
-ethical issues - severely ill patients wont be able to receive rewards as they arent able to complete target behaviours, so may suffer discrimination. may also be seen as demeaning
-behaviour may improve due to increased staff attention etc instead of token economy - hard to study as when TEs are introduced, all patients are involved instead of control and experimental group
interactionist approach - diathesis stress model
-states that both a biological vulnerability to SZ and an environmental stress trigger are necessary to develop the condition
-additive nature - vulnerability and stress can combine in different ways eg. minor stressors can lead to onset in person w high level of bio vulnerability and major stressors can lead to onset in person w low level of bio vulnerability
examples of stress + research for them (interactionist approach)
- childhood trauma - varese - found children who experience severe trauma have a 3x greater risk of developing SZ
- urban environments - vassos et al - found risk of SZ in urban environments to be 2.4x greater than in rural areas
strengths of interactionist approach
-useful approach for treatment - tarrier et al - found patients given combination of drug and therapy treatment showed lower symptom levels than those just taking drugs
-research support - tienari et al - found adopted children w sz bio parent were only more likely to develop sz if their adopted family was classified as disturbed
limitations of interactionist approach
-research against stress - romans-clarkson - found no rural-urban differences in mental health in women in NZ
-research against - vulnerability may not be exclusively genetic - verdoux et al - found risk of developing SZ is 4x greater in ppl who experienced birth complications
