Schizophrenia Flashcards
Classification
What schizophrenia is
+ positive symptoms
- negative symptoms
Differs depending of classification system used
DSM5
ICD11
positive symptoms of schizophrenia
hallucinations - unusual extra-sensory experiences, hearing voices, seeing things
delusions - believing things that aren’t true, paranoia, believing they’re important
jumbled speech
negative symptoms of schizophrenia
speech poverty - reduced amount or quality of speech
avolition - lack of drive and motivation to achieve goals
lack of emotion
what is the DSM?
list of mental health disorders which helps diagnosis
needs at least one positive symptom
Reliability and Validity
Reliability - not consistent
- Gender bias
Longenecker - men 50% more likely then women
- Culture bias
Escobar - American Americans more likely
Swartz - African Americans 2.4x more likely
Cheniaux - more likely diagnosed with ICD than DCM, not consistent
+ Osorio
.97 inter rated reliability in diagnosis, is reliable
Validity - not accurate
- Symptom overlap - diagnose as wrong disorder
- Cheniaux - more likely diagnosed with ICD than DCM, not consistent so not all diagnoses accurate
Diagnosis inconsistent - not everyone diagnosed that should be, treatments less effective
Diagnosis not accurate - wrong condition, treatments less helpful
what is comorbidity?
having 2 or more conditions at once
harder to diagnose
reduces validity - may be another issue
reduces reliability - others Amy diagnose as another issue
biological explanations for SZ
genetic
neurotransmitters (dopamine hypothesis)
neural correlates
genetic explanation for SZ
inherited in genes and runs in families
polygenic - multiple candidate genes found, increase someones likelihood
Gottesman
MZ - 48%
DZ - 17%
concordance rates for SZ
evaluation of genetic explanation
+ Gottesman (48% DZ and 17% MZ)
shows there is some genetic influence
+ Tienari - children adopted from SZ mothers more likely to developed SZ than control group
shows genetic factors more influential than environment
- concordance rates not 100%, must involve other factors
the dopamine hypothesis (neurotransmitters)
SZ caused by high levels of dopamine transmission
drugs work by blocking the receptors for dopamine so less is transmitted
evaluation of dopamine hypothesis
+ drugs that block dopamine are effective, suggests it must be caused by high levels
Thornley et al - typical antipsychotics more effective than placebo
+ drugs that increase dopamine levels are shown to cause SZ symptoms
+ real world application, effective drug treatments
- drugs only help positive symptoms, doesn’t explain negative ones
- correlation doesn’t mean causation
neural correlates in SZ
structural abnormalities in brains linked with SZ
Johnstone et al - SZ patients found to have enlarged ventricles
- however non SZ patients can have it
- correlation doesn’t mean causation
psychological explanations for SZ
family dysfunction
cognitive explanations
outline family dysfunction explanation
family issues of conflict, criticism and communication issues caused SZ
schizophregenic mother - mother who is cold and controlling
- leads to stress and distrust
double bind communication - faulty communications means child receives mixed messages
- causes delusions and speech poverty
expressed emotions - living with high ee has high levels of criticism and is hostile
- links to relapse in patents
evaluation for family dysfunction
+ Read et al - 69% female patties received abuse in childhood, show family experiences have influence
+ real world application, lead to family therapy
Pharaoh et al - family therapy reduces readmission
- research is retrospective, may have distorted memories especially with SZ
- reductionist, evidence for biological explanations, Gottesman
- blames family
outline cognitive explanation
caused by dysfunctional thought processing
leads to delusions and speech impairments
lack of central control - unable to suppress automatic responses
- leads to disorganised speech
lack of metarepresentation - ability to reflect on own actions
- leads to hallucinations and delusions
evaluation of cognitive explanations
+ Stirling et al - SZ patients performed poorly on cognitive tasks, shows they process information differently
+ real world application. led to effective CBT for SZ
NICE - reviewed treatments, CBT effective at reducing rehospitalisation
- evidence for biological explanation, Gottesman
- faulty thought processing may be used by neural correlates or neurotransmitters, a symptom not a cause
psychological treatments for SZ
family therapy
CBT
CBT for schizophrenia
based on identifying and changing faulty cognitions
uses basis of CBT and Ellis’ ABC model to determine cause and consequences to be changed
reality test and challenge hallucinations and delusions
gives them an explanation for their symptoms which can reduces distress
evaluation of CBTp
+ NICE review of treatments, CBT effective in reducing rehospitalisation
most effective with CBT and drugs
+ no side effects, unlike drugs
- doesn’t address cause just helps symptoms
- evidence for biological explanations, biological treatments better?
- more expensive and time consuming than drug therapies
outline family therapy
therapy with whole family not just individual
aims to reduce conflict and ee in households, which can reduce relapse rates
evaluation of family therapy
+ Pharaoh et al - reduced readmission after family therapy, effective
+ no side effects
- doesn’t treat cause, only symptoms
- evidence for biological explanations, biological treatments better?
diathesis stress model
combines biological and psychological factors
suggests those more biologically vulnerable may be more likely to develop it when exposed to environmental stressors
biological vulnerability + environmental stressor
leads to schizophrenia
outline biological treatments for SZ
drug therapies
antipsychotic drugs work to reduce dopamine levels by blocking receptors to stop transmission
sides effects include dizziness and blurred vision, agranulocytosis
typical :
older
more side effects
only treat + symptoms
effects dopamine
atypical:
neweer
fewer side effects
treats + and - symptoms
effects dopamine and serotonin
evaluation of drug therapy (biological)
+ Thornley et al - typical drugs more effective than placebo, effective
+ cheaper and easier than therapy
+ can be used alongside therapy
Tarrier most effective with CBT and drugs
- still has side effects, dry mouth dizziness, although fewer with atypical
stops people taking it, less effective - ethical issues, doesn’t help patients just control behaviour
token economies in SZ
behavioural treatment bassoon operant conditioning, used to manage SZ
uses positive reinforcement to reward desirable behaviour
tokens can be earn and exhacnged for rewards
evaluation of token economies
+ Dickerson et al, shows use of token economies is effective
+ helps people in institutions
- lacks ecological validity, doesn’t apply to real world, behaviour may stop when not rewarded
- unethical, most ill patients less able to participate so don’t get helped, not always effective, desert actually treat cause
Read et al
retrospective study of SZ patients
69% female patients experienced abuse in childhood, shows experiences influence SZ
supports psychological - family explanations
Thornley et al
meta analysis shows atypical more effecting than placebo
supports birlgicsl treatments and causes (dopamine hypothesis)
Cheniaux et al
disagreement in diagnosis of same 100 patients
more likely to be diagnoses with ICD than DSM
shows diagnosis is not reliable or valid
NICE review of treatments
CBT, drugs and family therapy effective
supports interactionist and all treatments
Tarrier
CBT and drugs most effective when used together
Gottesman
48% identical
17% non identical
concordance rates for SZ
supports genetic explanation
limitation of psychological explanations and treatments
Outline Interactionist approach
Caused by biological, psychological and environmental factors
Diathesis stress model combines the effect of internal vulnerability and external triggers
Vulnerabilities- genetic and childhood trauma effecting brain development
Triggers - negative psychological experiences eg stress, drugs
Explanation has developed - previously a single gene, now polygenic
Treated with a combination of treatments, psychological therapy and drugs
Evaluate Interactionist approach
Explanation
Tienari - biological
Read - experiences
Tienari - adopted children of schizophrenics, more likely to develop it when adopted into household of high ee, shows combination of genetics and environment
Treatments
Tarrier - combined treatments, drugs and CBT most effective when used together
NICE - reviewed all treatments, all effective
- ignores some factors such as neutrotransmitters
