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