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
MRI scans
detect small tumours and provided detailed information about structure
Functional MRI scans
provide structural and functional information
SQUID magnetometry
produces accurate images of brain activity by measuring the magnetic fields generated when neurones are activated - however, outside courses of magnetism can affect measurements
maguire - taxis - method
natural experiement
MRI scans from 16 licensed male London taxi drivers were compared with a control group who had never driven taxis
all participants in good general, neurological and psychiatric health and had an average age of 44
all taxi drivers had been working for at least 18 months
maguire - results
average size of the right posterior hippocampus was significantly larger in the taxi divers
the increased size was relative to the length of time that the taxi diver had been working
maguire - conclusion
the hippocampus is responsible for storing a spatial representation of the environment - it seems that the specific navigational demands of the taxi drivers have resulted in physical change
maguire - evaluation
can be used to help those with brain injuries as it shows that the size of the structures within the brain can be influenced through cognitive activity
this means rehabilitation could be tailored to the specific needs of individuals and their injuries
the study had a good level of control and could be replicated, which increases its reliability
the sample size was small and the results can only be generalised to male taxi drivers in london
the results can’t be generalised to other areas of the brain
neurochemistry
about nervous system and neurotransmitters
too much or too little of a particular neurotransmitter may produce psychological disorders eg dopamine and schizophrenia
strengths
the approach can provide evidence to support or disprove a theory - its a very scientific approach
if a biological cause can be found for mental health problems or for unwanted behaviour such as aggression, then biological treatments can be developed to help individuals
