biological approach Flashcards
2 assumptions of the biological approach
- suggests that everything psychological is first biological, therefore to understand behaviour we must look to biological structures and processes within the body such as genes, neurochemistry, neuroanatomy and the nervous system
- favours the use of the experimental method in explaining behaviour. technology is used to record physiological data. case studies are used to provide information on the localisation of function within brain structures
what side of the debate is the biological approach on?
the nature side
THE INFLUENCE OF GENES ON BEHAVIOUR
where are genes found?
in our chromosomes which parents pass on to offspring in their sex cells in reproduction
what do genes consist of?
DNA
what does DNA code?
physical features of an organism e.g., eye colour and heights, and psychological features e.g., psychological features and intelligence
who are genes passed on from and to?
from parent to offspring
what is the genotype?
the particular set of genes that a person possesses
what is the phenotype?
physical appearance or other characteristic e.g., behaviour, of that individual that results from inherited information
is there always a direct relationship between this?
it is expected but is not always the case
how many chromosomes do we inherit from each parent?
23
what kind of studies does the biological approach conduct?
twin studies, adoption studies and family studies
what do these studies determine?
the likelihood that certain traits have a genetic basis e.g., intelligence, personality
why are twin studes used?
since the majority of twins share the same environments
what are MZ twins?
twins that share 100% of their genes
what are DZ twins?
twins that share 50% of their genes
what are concordance rates?
the presence of the same trait in both members of a pair of twins
what do concordance rates allow us to do?
estimate the extent to which a behaviour or characteristic has a genetic basis
Gottesman and Shield (1991) method
a meta-analysis of 40 twin studies into the role of genetics in schizophrenia
Gottesman and Shield (1991) results
having an identical twins with schizophrenia gave you a 48% chance of developing schizophrenia. this reduced to 17% in DZ twins
Gottesman and Shield (1991) conclusion
schiophrenia has a strong genetic basis
Heston (1966) method
47 adopted children whose biological mothers had schizophrenia were studied. the control group consisted of 50 adopted children whose biological mothers didn’t have schizophrenia, the children were followed up as adults and were interviewed and given intelligence and personality tests
Heston (1966) results
of the experimental group, 5 of the 47 became schizophrenic, compared to 0 in the control group. another 4 of the experimental group were classified as borderline schizophrenic by the raters
Heston (1966) conclusion
supports the view that schizophrenia has a genetic basis
THE INFLUENCE OF BIOLOGICAL STRUCTURES IN BEHAVIOUR
what is the largest part of the brain?
the cerebrum, making up 85% of the total mass of the brain
what is the outer surface of the brain?
the cerebral cortex
what is the cerebral cortex responsible for?
‘higher order’ function such as thought and language
what is the cerebrum made up of?
vast numbers of interconnected neurons and is seperated into 2 halved called hemispheres
what is the left hemisphere responsible for?
- speech
- analysis
- time
- sequence