Schizophrenia - Paper 3 Flashcards
schizophrenia into
- means split mind
- affects 1% of the population
- identical twins have concordance rate of 48%
- men are 1.4x more likly to be diagnosed than women
- men diagnosed in late teens/early 20s
- women tend to be diagnosed in late 20s
- working class are more likly to be diagnosed
symptoms
- no singular definding sympton
- manifests differently in everyone
- postive symptom - are additonal expirences beyond those ordinary existence (hallucinations and delusions)
- negative symptom - invloves the loss of usal abilities and experiences (included avolition and speech poverty)
postive symptoms
Postive symptoms
- hallucinations
- delusions
- speech disorganisation
- uncontrollable laughter or tears
- rocking back and forth
- catatonia
hallucinations
Postive symptoms
- sensory experience of things which are not there
- E.G voices (often critising) or visions`
delusions
Postive symptoms
- irrational beliefs
- beliefs that have no basis in reality
-
presecutory (suspicious/parano
id) - grandiose (extreme importance)
- religious (are god or can speak to him)
speech disorganisation
Postive symptoms
- changing conversation topic quickly and randomly , or speech become incoherent
catatonia
Postive symptoms
- this is characterised by unusal movement
- sufferers or shows repetive puposless overactivity
negative symptoms
- flat affet
- avolition
- speech poverty
- social withdraw
- catatonia
flat affect
negative symptoms
- lack of emotional expressivness
- E.G an expressionless face and voice
avolition
negative symptoms
- lack of motivation to do everyday tasks
- 3 signs of avolition - poor hygiene , lack of work/education , lack of energy
speech poverty
negative symptoms
- reduced frequencey and quality of speech
catatonia
negative symptoms
- staying still
diagnosis
- symptoms have to last for at least a month
- ICD 11 (international classification of diease)
- DSM 5 (diagnostic statistical manual)
- The DSM requires both negative and positive symptoms to diagnose
- ICD only requires negative symptoms and recognises subtypes (paranoid , hebeprenic , catatonic)
hebephrenic schizophrenia
types of schizophrenia
behaviour is disorganised and without purpose
undifferentiated sz
types of schizophrenia
- dont fit in one type (has lots of different types)
catatonic SZ
types of schizophrenia
- unusal movements
paranoid schizophrenia
types of schizophrenia
- hallucination/delusions
residual sz
types of schizophrenia
- may be diagnosed if they have a hisotry of psychosis
external reliability
diagnosing schizophrenia
- consitency of diagnosis of the same patient (over time, or using different methods) given no change in symptoms
inter - rater reliability
diagnosing schizophrenia
- the consistency of diagnsis of the same patient given by different psychiatrists
problems with the reliability of diagnosis - cheniaux
diagnosing schizophrenia
- to test reliability sz
- 2 psychiatrists diagnosing 100 patients with DSM5 and ICD
- 1)DSM: 13 ICD: 24 - low external (same patient should recive the same diagnosis) (inconsistent )
- 2) DSM:26 ICD: 44 (low interrate as nearly double)
Jakobsen
diagnosing schizophrenia
- tested reliaility of diagnosing SZ (ICD , DSM)
- tested 100 patients with a correlation of 0.87
- books agreen with eachother - high external validity
validity of SZ
diagnosing schizophrenia
- the extent to ehich SZ is actually a syndrome with specific characteristics , signs and symptoms (or is it a mixture of others or something else misdiagnosing)
validity of diagnosis
diagnosing schizophrenia
- are we correctly diagnosing people who have the disorder (E.G are we actually testing for what we think we are testing)
how does SZ affect different people
diagnosing schizophrenia
- people (cultural/population)
- places (ecological)
- time (temporal)
a problem - SZ has overlapping symptoms of the disorder
diagnosing schizophrenia - evaluation
- evidence - depression has many symptoms which overlap - flat affect , avolition , speech poverty and lack of hygiene
- bipolar - delusion , speech disorganisation
- explain - sometimes the same patient could be diagnosed SZ using one classification and a different one for another
- link - low external validity
a problem - the disorder is often comorbid
diagnosing schizophrenia - evaluation
- explain - comborbidity means more than one illness or disease occuring in one person at the same time
- buckley looks at patients and found with SZ and found 50% also had depression , 23% had ocd
- explain - which diagnosis is causing which symptom
- link - cant tell what is causing what
a problem - diagnosed differently in male and females
diagnosing schizophrenia - evaluation
- evidence - longenecker saw that since the 1980s more men than women have been diagnosed , when before there was no difference
- explain - could be different as social norms have changed and women play a different role in society
- women are better at hiding their emotions and less likly to be diagnosed
- link - lowers population validity
candidate gene
biological explanation of SZ
a gene whose chromosmal location is associated with a particular disease or other genotype
genetics
biological explanation of SZ
our genes carry infomation that gets passed from one generation to the other
neural correlations
biological explanation of SZ
brain activity that corresponds with and is neccessary to produce a particular experience
dopamine
biological explanation of SZ
- a neurotransmitter
- dopamine plays a role in how we feel pleasure
- its a big part of our unique human ability to think and plan
aetiologically heterogenous
biological explanation of SZ
- a number of different combinations of genes wich lead to the illness
concordance rate
biological explanation of SZ
- the percent of cases in which both members of a pair have a particular attribute
genetic councilling
biological explanation of SZ
- a way for people to understand how genetic illnesses can affect them and their family
polygenic
biological explanation of SZ
- phenotype is influenced by one or more gene
biological explanation of SZ - genetic
- polygenic disorder - ripeke et al found 108 genes contribute to SZ
- aetiollgically heterogenous - multiple variations of genes
- code for dopamine (imbalances)
Gottesman (supporting evidence)
biological explanation of SZ - genetic
- MZ twins - 48%
- DZ twins - 17%
- parents - 6%
- siblings - 9%
- grandparents - 5%
genain quadruplets
biological explanation of SZ - genetic
- all 4 of them devloped sz in their 20s
- abusive parents
- grandmother had SZ
adoption studies (supports)
biological explanation of SZ - genetic eval
- look at the impact of nurture on children who are raised by parents who are not their biological parents
- as have no biological traits connection between parents and child
- if they grow up to share traits of parents than the traits are probs due to nurture
- suggests its important but not 100%
brocas area
biological explanation of SZ - neural correlates
- function - responsible for speech production
- role in SZ - to much dopamine in this area may be associated with speech poverty/auditory hallucintation
prefrontal cortex
biological explanation of SZ - neural correlates
- function - helps people thing logically and organise their thoughts
- role in SZ - many SZ have lower activity in this area, which could be linked to delusions and disorganised thoughts
visual cortex and audioty cortex
biological explanation of SZ - neural correlates
- function - process infomation recieved from the eyes and the ears
- role in SZ - sz have the same ativity in these areas when they have hallucinations as a sane people do when they have genuine visual and auditory experiences
basal ganglia
biological explanation of SZ - neural correlates
- function - located deep inside the brain and affects movement and thinking skills
- role in SZ - research has shown that this is larger in SZ, which could cause motor dysfunction
amygdala
biological explanation of SZ - neural correlates
- function - responsible for basic feelings such as fear , lust and hunger
- role in SZ - smaller in SZ so can link to a loss of emotion (flat affect)
dopamine
biological explanation of SZ - neural explanation
- function - responsible for feelings of pleasure and also affects thinking and movement
- role in SZ - low levels in ceratin areas in the brain area are linked to a loss of pleasure
- high levels in brain areas are linked to a postive symptom
superior temporal gyrus
biological explanation of SZ - neural explanation
- function - associated with attributing stimuli to internal and external causes
- role in SZ - in sz activity levels are lower which can lead to hallucinations and feelings they are in no control of their own body
- can tickle themselves
ventral striatum
biological explanation of SZ - neural explanation
- in sz actvity levels are low, resulting in a loss of motivation (apathy and avolition)
negative- causation
biological explanation of SZ - neural explanation (eval)
- causation does not equal causation
- is it big/small bc of the SZ
- or is te SZ bc of it being big/small
synaptic tranmission recap
biological explanation of SZ - dopamine hypothesis
- nerve impulse travels down the axon in the presynaptic neuron
- impulse reaches the axon terminal of presynaptic neuron
- this triggers the realse of neurotransmitters from its vesicles into the synaptic gap
- neurotransmitter diffuses across synaptic gap
- neurotransmitter bind to a receptor site on the postsynaptic neuron
- this triggers a new impulse in the next neuron, and the process begins again, passing the message on
- process of summation happens where a message either excitation occurs or inhibiton
- the neurotransmitter travels back to the presynaptic neuron and is repackged into vesicle (reupatke)
bold - electrical process non bold - chemical process
research
biological explanation of SZ - dopamine hypothesis
- amphetamines (drug that increase dopamine) produce symptoms which are similar to those expirenced by some with SZ
- randrup et al (1966)
- behaviour similar to that found with SZ was induced in rats by administering amphetamines and the effect was reversed with antipsychotic drugs
- iverson (1979)
- did some post mortem examinations on people with Sz and without
- found a higher number of dopamine receptors in people with SZ than a normal individul = supports the idea of overactive dopamine levels in someone in SZ
dopamine hypothesis
biological explanation of SZ - dopamine hypothesis
- part 1 - hyperdopaminergia
- part 2 - hypodopaminergia
part 1 - hyperdopaminergia
biological explanation of SZ - dopamine hypothesis
- the dopamine hypothesis firt assume that positive symptoms of SZ come from hyperdopaminergia (too much dopamine) in the subcortex (central brain areas)
- E.G broacas area is for speech production , so excess dopamine in boracs area is thought to lead to the symptom speech disorganisation
- negative symptom - to much activation - shuts down - speech poverty
part 2 - hypodopaminergia
biological explanation of SZ - dopamine hypothesis
- negative symptoms of SZ can be caused by hypodopaminergia (low levels of dopamine) in the cortex (outside area)
- E.G the prefrontal cortex is for problem solving so low levels of dpamine in this area is though to lead to the symptoms of disorganisation
- therefore both hypo and hyperdopaminergia can cause symptoms of SZ
general evaluations of biological explanation
- biological determinism
- reductionism - way to simple
- scientific credibility - emperical evidence in brain scans and dna testing
- real life application - drugs reduce symptoms
weakness - glutamate
biological explanation of SZ - dopamine hypothesis (eval)
- central role of glutamate
- from post mortem and live scanning
- was found in many parts of the brain
- as well as other genes
- may be a more important one than dopamine
strenght - L-dopa
biological explanation of SZ - dopamine hypothesis (eval)
- L-dopa is a drug given to patients with parkinson disease
- a dopaminse synthesis medication
- this means it increase dopamine levels in the brain
- this medication can reduce symptoms resembling acute sz in non-psychotic patients
types of antipsychotic drugs
drug treatments for SZ
- typical antipsychotics - used to treat positve symptoms
- chlorpromazine
- atypical antipsychotics - used to treat postive and negative symptoms
- clozapine
- risperidone
dopamine antagonist
drug treatments for SZ
- blocks dopamine recpetors in the brain reducing the action of dpamine
atypical antipsychotic
drug treatments for SZ
- clozapine binds to dopamine receptors but also works on serotonin and glutamate
- sideaffects are fewer but may be more fatal
- risperidone developed in the 1990s, works in the same but also clozapine, fewer side effects
antipsychotics
drug treatments for SZ
- reduce intensity of symptoms, espically positive ones
tardive dyskinesia
drug treatments for SZ
- side effcts of typical antipsychotics
- uncontrolable movements of the mouth and face and tounge
- blinking
- puckering, pouting , smacking (mouth)
- biting chewing , clenching , mouth open and lateral movements (jaw)
typical antipsychotics
drug treatments for SZ
- first generation
- since 1950s
- works as dopamine antagnosists and include chlorpromazine
similarities of typical and atypical drugs
drug treatments for SZ
- lowers the amount of dopamine
- bad side affects
- typical - tardive dyskinesia
- aytipical - tardive agranuloctosis (reduction in white blood cells
differences between atypical and typical drugs
drug treatments for SZ
- typical - only affects dopamine and only for postive symptoms
- aytpical - affects dopamine and serotonin and for both postive and negative symptoms
(-) drugs treat the symptoms
drug treatments for SZ - evaluation
- they dont know the exact cause for SZ
- they are not treating the cause
- can only reduce the effect of the illness
(-) relapse rates are high
drug treatments for SZ
- body gets used to the drug
- bodies begin to compensate and chnage
- therefore dependancy becomes an issue
(+) thornley - supporting evidence
drug treatments for SZ
- reviewed studies comparing chlorpromazine to a placebo
- data from 13 trials with 1121 participants showed chlorpromazine was associated with better overall functioning and reduced symptoms severity and lower relapse rate
(+) meltzer - supporting evidence
drug treatments for SZ
- concluded clozapine (atypical) is more effective that typical antipsychotics (it was effecting 30-50% of cases where typical antipsyhcotics had failed
- also had less side affects
- shows that new ones are better and improving , so more efficent that typical ones
(-) - bad side effects
drug treatments for SZ
- tardive dyskinesia , tardive agranuloctosis and neuroleptic maligant syndrome (results in high temperature , delirium , coma and can be fatal)
- around 1 in 4 people will suffer from this side affect
- harmful and traumatic
family dysfunction
psychological cause of SZ - Family dysfunction
- is not a cause of SZ
- a risk factor - can lead to SZ in people who are already vulnerable (e.g diathesis stress model)
family dysfunction
psychological cause of SZ - Family dysfunction
- schizophrenogenic mother
- double bind
- expressed emotion
schizophrenogenic mother
psychological cause of SZ - Family dysfunction
- based on freudian principles
- the schizophrenogenic mother was proposed as a cause from SZ to emerge in a child
- these mothers dont have SZ but have children with it
- these mothers are described as rejecting , cold , controlling , moralistic and fearful of intamcy
- leads to tension , conflict and secrecy in the family
- leads to paranoid delusions and persecutory delusions
double bind - bateson 1975
psychological cause of SZ - Family dysfunction
- confusing parenting style where the parent contradicts themselves and the child gets conflicted messages
- E.G the child is punished for what they were asked to do
- love withdrawal - where the children are punished for their mistkaes by parents saying they dont love them
- child devlopes an understanding o the world that is confusing and dangerous
- leads to disorganised thinking, paranoid delusions , speech poverty and social withdrawal and flat affect
expressed emotion
psychological cause of SZ - Family dysfunction
- family communication style
- critical comments through both tone and content , occasionally accompanied by violence
- hostility towards the patient , including anger and rejection
- emotional over involement in the life , including needless self-sacrifice
- risk of relapse is high is lots of factors or a vunreable person could devlop sz
emotional overinvolvement examples
psychological cause of SZ - Family dysfunction
- “you can always come to talk to me about your personal life”
- “what did you father say about me last night when he was upset”
- going through childs phone
hostility examples
psychological cause of SZ - Family dysfunction
- if you do that again i will shout
- whish you were never born
- dont make me do something i will regret
critism examples
psychological cause of SZ - Family dysfunction
- cant you do anything right
- youre the reason we are all unhappy
schizophrenogenic mother evaluation ideas
psychological cause of SZ - Family dysfunction
- biased
- no supporting evidence
- soically sensitve
- lack creditbility and too subjective
- deterministic
double bind evaluation ideas
psychological cause of SZ - Family dysfunction
- soically sensitve
- is it significantly more prevent in SZ families
- self report
expressed emotion evaluation ideas
psychological cause of SZ - Family dysfunction
- socially sensitve
- correlations/causation (looking after someone who has SZ can be extremely tiring and emotional)
supporting evidence
psychological cause of SZ - Family dysfunction
- read 2005 - reviewed 46 studies of child abuse and SZ in adult hood and concluded that 69% of adult patients with a diagnosis of SZ had a hisotry of child abuse
- berry et al 2008 - adult with insecure attachment to their primary career are alose more likly to develop SZ
negative of schizophrenogenic mothers
psychological cause of SZ - Family dysfunction - eval
- by the 1980s research concluded that there was no such thing as a schizophrenogenic mother
- this is subjective as it was determined by seeing parents for crazy making characteristics
- this is unscientific because one criteria for science is to be objective
- many sz have been found to have mothers who do not fit this criteria
- the theory has been critised for actually hindering progress and understanding of SZ
strengths of expressed emotion
psychological cause of SZ - Family dysfunction - eval
- brown
- recovering SZ, discharged from hosptial and follwed up over a 9 month period
- interviews with family member conducted to determine the level of expressed emotion
- also looked at how many patients relapsed
- in the high expressed emotion families = 58% relapse rate
- in low expressed emotion families = 10% relapse rate
- clear link between expressed emotion and SZ
strength and weakness of double bind
psychological cause of SZ - Family dysfunction - eval
- berger - found that SZ reported higher reall of double bind statements by their mothers than non sz
- HOWEVER
- self report - dont know what is real and what was delusions
- not reliable
- recall might be affected by disorder
- liem - found no difference in patterns of parental commincation in families with a SZ child in comparison to normal families
congnitive explanation
psychological cause of SZ - cognitive explanation
- SZ is characterited by disruption of normal cognitve processing
- this has led to cognitive psychologist to explain the disorder as a result of dysfunctional though processing
- this equals lower than usual levels of processing (possibly cause by biological factors such as neural correlates) suggests that cognition is likly to be imparied
three parts
psychological cause of SZ - cognitive explanation
- metarepresentation - christian frith 1992
- central control - christian frith
- auditory selective attention
metarepresentation - christian frith 1992
psychological cause of SZ - cognitive explanation
- when we think, we hear thoughts in our head
- metarepresentation is reflecting on our own thoughts
- suggested that SZ fault to monitor and reflect upon their own thoughts correctly , masattributing them to the outside world = dysfuntion in metarepresntation
- when someone has aduotry hallucinations they belive someone is in the external world communicating but its acc their own inner speech being misinterpreted
- this is refered to alein control symptoms bc the sufferers feel as if external forces are influencing their thoughts and actions have no personal control
central control - christian frith
psychological cause of SZ - cognitive explanation
- central control is the ability to suppress automatic repsonses such as thoughts and associations
- frith suggests that SZ fail to supress these automatic thoughts
- = derailment of thoughts and sentences
- = disorganised thinking and speech
auditory selective attention
psychological cause of SZ - cognitive explanation
- the process by whihc the brain selects whihc sounds to respond to
- our brain selects what to ignore and pay attention to
- some people have selective attention impairment
- this means they experience potentionally overwhelming levels of infomation from the external and inner world
- = the negative symtom may occur as SZ have to keep mental stimulaition to a managble level
- = its thought catatonic SZ have no choice but to withdraw from the world
research - stirling 2006
psychological cause of SZ - cognitive explanation-could be used for eval
- compared 30 sz to 18 control
- found that the SZ took twice as long to complete the stroop test
- thi suggests they are less able to supress automatic responses while reading
- A03 - this is strength for the cognitve theory as it shows the lack of central control in SZ and is able to explain why SZ have derailment of thoughts and disorganised speech
(-) describes , does not explain
psychological cause of SZ - cognitive explanation - eval
- the cognitve approach does describe how infomation prosessing is affected by SZ
- but it does not provide an explanation of what causes it
- = does not offer an understanding about te intial cause
- cogntive disturbance might be symptoms of the disorder rather than an explanation
(+) links with biological explanation
psychological cause of SZ - cognitive explanation - eval
- compatiable with bio expl
- genes could be responsible for these dysfunctional thought patterns
- there is a link bewteen neurological abnormalities wich cause cogntive difficulties
(-) other cognitve deficits dont correlate with SZ
psychological cause of SZ - cognitive explanation - eval
- if dysfunctional thought processing is said to be the root cause of the disorder then it would follow that childhood diffiuclties in infomation processing (such as dyslexia) would correlate with the later onset of SZ
- however there is no scientific evidence to support this link
- so there must be other causes/risk factors = fault cogntiion is not a complete explanation by itself
CBT
psychological cause of SZ - psychologcial therapies
- usally 5-20 sessions
- cbt changes thoughts in order to change behaviour
- helps patient to identifty irrational thoughts and try to change behaviour
- may involve arguments or discussion of how likly the beliefs are to be true
- their irrational beliefs are changed
how does CBT help?
psychological cause of SZ - psychologcial therapies
- helps patients to make sense of how delsuions and halluctinations impact their feelings and behaviours
- the patient as a scientist method helps the SZ believe what they learn from CBT (that delusions arent real) because they discorved it themselves and werent told
- understanding where the symptoms came from - E>G belive the voices and thinking are demons - can see that they arent real which will lower anxiety and make them less scary
- this does not cure SZ but helps manage their symptoms
(+) supporitng research chadwick
psychological cause of SZ - psychologcial therapies - eval CBT
- pateint had delusions that his thinking could influence the future
- however the patient failed to predict what would happen in 50 video clips
- this provides evidence that his delusions were false which helped relieve symptoms
(+) supporting study jauhar
psychological cause of SZ - psychologcial therapies - eval CBT
- reviwed results of 34 studies of CBT and concluded it has a significant but fairly small effect on postive/negaitve symptoms
(-) cbt needs motivation
psychological cause of SZ - psychologcial therapies - eval CBT
- need to attend the sessions
- need to be able to hold a convo
- undertsand own thoughts = cant work for everyone
(-) cbt may involve challengeing a person paranoias
psychological cause of SZ - psychologcial therapies - eval CBT
however what point does this interfere with an individuals freedom of thought
tocken economy
psychological cause of SZ - psychologcial therapies - token economy
- based on behaviourist principle
- operant conditiong - postive & vicarious reinforcement makes behaviour more likly
- tokens count as a secondary reinforcer - enables patient to get a reward
- many in psych hospitals when they are there for a long time
- to manage maladaptive behaviours of SZ (usaslly bc in hopsital for so long - bad hygiene)
- prepares them to live in the outside world
- rewards - sweets , cigerattes , walks outside , room cleaned
- the tokens remove delay discounting as the token is an immediate secondary reinforcer
- still provides postive reinforcement quickly after behaviour has been performed
evaluation for token economy
psychological cause of SZ - psychologcial therapies - token economy
- (+) - show to be effective in reducing negative symptoms for pople with SZ in a hospital setting
- (-) once that person leave the hospital , the methods of token ecomony are lost as they dont have the reinforcement
- (-) the rewards are sometimes things that should be free (walks outside)
- (+) no side effects like drugs
- (-) not fair on more severly SZ patients who find it harder to maintain the good behviours
evaluation into token economy is weak
psychological cause of SZ - psychologcial therapies - token economy
- research into token economy is weak because studies comparing token economy to standard care are unable to randomly allocate particpates to conditions
- McMonagle and Sultana
- searches the database of studies into token economy vs standard care and found only three studies where patients had been randomly allocated to conditions, and only one showed improvements
family therapy
psychological cause of SZ - psychologcial therapies - family therapy
- therpay that happens when the patient has been relased from hopsital
- the therapists works with the family and patient to devlop strateries to cope better with the mental disorder and its symptoms
- normally two therapists work woth the patient and the family within the home
- lasts for 3-12 months with sessions every 2-4 weeks
- a minimum of 10 sessions
how does family therapy work?
psychological cause of SZ - psychologcial therapies - family therapy
- the aim is to reduce the high level of expressed emotion within the household which could (or is) causing the relapse of SZ
- they will help family members balance their tme between helping the SZ and living their own life = rediced anxiety/stress/anger
general evaluation
psychological cause of SZ - psychologcial therapies
- psychological treatment help make SZ more manageable and thus improve quality of life
- CBT - allows patients to make sense of symptoms
- family therapy - redcues stress for family and patients
- tocken economy - make behaviour more socially acceptable so they can reintergrate into society
- but all of them failt to cure - weakness to all psychologcal treatments
diathesis stress model
interactionist approach to SZ - diathesis stress model
- is an interactionist model which suggests a person may be born with a predisposition towards SZ that is then triggered by a stresser
- suggests someone needs the diathesis part and stress part to develop SZ
- if someone has a genetic vunrabilitiy but has a supportive social environment with no acute stressers , they will not develop the illness
- if thye have a very stressful environment but no early predispostion then they wont devlop the illness
the orginal model - Meehl
interactionist approach to SZ - diathesis stress model
- believed diathesis was entirely genetic - the result of a single schizogene
- this led to the devlopment of a biological based schizotypic personality, one characteristic is sensitvity to stress
- if a person doesnt have the schizogene then no amount of stress will lead to SZ
- however, in carriers of the gene, chronic stress through childhood and adolescence, particulary a schizophrenic mother could result in SZ
newer models
interactionist approach to SZ - diathesis stress model
- now clear that many candiate genes increase gentic vulnerability
- no single schizogene - ripke
- trauma can become the diathesis rather than the stresser - ingram and luxton
- read - proposed that a neurodevlopmental model in whihc early trauma in early devlopment alters the devloping brain
- E.G the hypothalamic-pituitary-adrenal system (HPA) (FLIGHT OR FIGHT) becomes over active and the person is more vulnerable to later stress
cannabis - houston et al 2008
interactionist approach to SZ - diathesis stress model
- orginally stress was seen as psychological in nature - particularly related to parenting
- modern defintion of stress included includes anything that risks riggers SZ - CANNABIS
- cannabis is a stresser because it increases the risk of SZ by 7 times as it interferes with the dopamine system
- however most wont develop SZ from smoking cannabis there must be other vulnerability factors
supporting study - tienari
interactionist approach to SZ - diathesis stress model - evaluation
- aim - to examine the effect of genetic vulnerability and parenting style (over 20 years)
- sample - children dpted from 19,000 SZ finnish mothers (1960s and 70s), control group = adoptees with no genetic risk
- method - compared child rearing style and rates of SZ in the sample of children (two groups (critism , conflict , low emphathy) (non critical , no conflict , emphatic)
- findings - a high level of conflict and critism + low levels of emphathy from parenting linked to devlooment of SZ, but in children with genetic risk only
why do we use CBT and antipsychotics
interactionist approach to SZ - diathesis stress model - evaluation
- as we know there is not just one cause of SZ, and that the environment and biology work ectremely close together with SZ
- so therefore isnt one best way to treat it
(+) tarrier et al - supporting evidence
interactionist approach to SZ - diathesis stress model - evaluation
- effectiveness of combination treatment = support for taking an interactionist approach to SZ
- BUT
- treatment causation fallacy; just because combo treatments are more effective than bio or psych on their own doesnt mean the interactionist approach is correct (just the same as just because drugs work doesnt necessarily mean the disroder is biological in orgin)
twin studies
interactionist approach to SZ - diathesis stress model - evaluation
- when compare MZ and DZ twins there is not 100% concordance rate with MZ twins but always a higher percentage
- there are multiple things playing the role
- higher in MZ shows there is a biological factor
- environmental is not 100%
