Biological Explanation For Sz Flashcards
Genetic theory A01
States sz is hereditary and passed on from one generation to the next through genes
Persons born with a genetic predisposition to sz
Several maladaptive candidate genes such as PCM1 are involved (polygenic) increasing vunrability to developing SZ
Studies have shown that 108 separate variations are associated in risk of developing sz
What did Gottesmen find ?
Studies 40 twins found concordance rate for monozygotic twins was 48 % and only 17 % for dizygotic
Thus closer the genetic link with sz more of a chance of developing sz
Neural correlates brain structure or function
Nueral correlate of sz is enlarged ventricles
Meta analysis by raz and raz found over half of individuals tested with sz had increased ventricle size compared control group
Enlarged ventricles
Associated with damage to central brain areas and pre frontal cortex
This damage is associated with the negative symptoms of sz
Nueral correlates :dopamine hypothesis
Brain chemical messengers (neurotransmitters) appear to work differently in the brain of a patient with sz
Dopamine is widely believed to be involved as individuals with sz release too much dopamine
Or have large amount of DZ receptors on the post synaptic nueron
Hyperdopaminergia in the sub cortex
High dopamine actuvity in central areas of brain
May be associated with auditory hallucinations
Hypodopaminergia in the cortex
Low dopamine activity in pre frontal cortex
Has been associated with negative symptoms of sz such as avolitiom
RTS genetic theory Ao3 strength
RTS role of genetic in development of sz comes from Tierny
Studied 155 adopted children who has biological mother with sz
Found concordance rate of 10% compared to 1% in adopted children without sz parents
Provides significant support for role of genetics as role of social learning theory could have not been a factor as children were adopted
Increasing validity of genetics as biological explanation of sz
