biological approach 1980s Flashcards
three basic assumptions
human behaviour can be explained by looking at the biology - eg hormones, genetics, evolution and the nervous system
in theory, if we can explain all behaviour using biological causes, unwanted behaviour could be modified or removed using biological treatments such as medication for mental illness
experimental research conducted using animals can inform us about human behaviour and biological influences, bevause we share a lot of biological similarities
darwin’s theory of evolution
over time, individuals who are better adapted to their environment through having better genes are more likely to survive to reproduce and pass on their useful genes - those who are less well-adapted will be less likely to survive to reproduce and pass on their genes - eventually their less useful genes will be eliminated from the gene pool for that species - through this process of natural selection, early humans became better adapted to their environments - for instance, behaviours such as phobias and aggression may have evolved because of the survival advantage that they gave
genotype
the genes that a person has
phenotype
the characteristics that their genes produce - for example, hair colour, eye colour
genetics
genetics can explain psychological traits - these are things like gender behaviour, intelligence, personality and sexual orientation
genes also make some people more likely to develop things like mental illness or addictions
gottesman - twin study - method
gottesman carried out a meta-analysis of approximately 40 twin studies
gottesman - results
it was found that having an identical twin with schizophrenia there was a concordance rate of 48%
only 17% in non-identical twins
gottesman - conclusion
schizophrenia has a strong genetic basis
gottesman - evaluation
the meta-analysis was carried out on field studies, giving the research high ecological validity - because identical twins share 100% of their genes, it might be expected that both twins would always suffer from the same conditions
the fact that both twins had developed schizophrenia in only half of the cases means that another factor must also be involved
identical twins tend to be treated more similarly than non-identical twins, and so the family environment might play a large role
heston - adoption study - method
47 adopted children whose biological others had schizophrenia were studied
control group - 50 adopted children whose biological mothers didnt suffer from schizophrenia
the children were followed up as adults and were interviewed and given intelligence and personality tests
heston - results
of the experimental group, 5 of the 47 became schizophrenic, compared to 0 of the controlled group
another 4 of the experimental group were classified as borderline schizophrenic by the raters
heston - conclusion
the study supports the view that schizophrenia has a genetic basis
heston - evaluation
interview data can be unreliable and affected by social desirability bias
however - interviews are a good way of getting data in a naturalistic way
the adopted children whose mothers didn’t suffer from any conditions might have no shown any symptoms yet but it cannot completely be ruled out
PET scans
show which part of the brain are active during different tasks - by studying PET scans, we can link certain areas of the brain with particular functions - also allow us to see where the brain is most active when we are thinking about certain things - show average activity over a 60-second period
CAT scans
detect damaged parts of the brain, tumours and blood clots - brain structure is shown, not function
