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
what does the left hemisphere recognise?
- words
- letters
what is the right hemisphere responsible for?
- creativity
- patterns
- spatial
- context
what does the right hemisphere recognise?
- faces
- objects
what is each hemisphere divided into?
four parts known as lobes
what are the four lobes?
- frontal lobe
- temporal lobe
- parietal lobe
- occipital lobe
what is the frontal lobe involved with?
speech, thought and learning
what is the temporal lobe involved with?
hearing and memory
what is the pariteal lobe involved with?
sensory information such as touch, taste and pain
what is the occipital lobe involved with?
visual information
what is the CNS made up of?
the brain and spinal cord
what does the CNS do?
co-ordinates functions such as breathing, the heartbeat, eating and the senses
what is the PNS made up of?
the somatic and autonomic nervous system
what does the somatic system do?
receives information from the skin and is important in movement
what does the autonomic nervous system do?
governs the body’s reaction to threat and is important for survival
what is the nervous system composed of?
interconnected neurons
what are neurons?
long thin cells that cnvey messages from one place to another
how many neurons does the brain contain?
billions
where do neurons pass message from one neuron to the next?
via small gaps between the neurons called a synapse
how do neurons pass message from one neuron to the next?
by neurotransmitters
THE INFLUENCE OF NEUROCHEMISTRY ON BEHAVIOUR
what are neurotransmitters?
chemical messangers that act between neurons within the brain
what does this allow the brain to do?
process thoughts and memories
what do they have on one end?
dendrites
what are dendrites?
finger like structures surrounding a nucleus
what is on the nucleus?
a long extension called an axon which reaches to an axon terminal
what does the axon terminal of one neuron reach to?
the dendrites of other neurons
what is between the terminal and the dendirites?
a gap called a synapse
what is on the dendrites?
receptors of a certain shape prepared to receive the neurotransmitter from the axon terminals of the other neurons
what can levels of neurotransmitters affect?
mood, thought and behaviour in individuals
what does the dopamine hypothesis in schizophrenia suggest?
schizphrenia results from an excess of dopmine
what are hormones?
another type of chemical messanger
what does the endocrine system control?
the release of hormones into our blood stream
what does the endocrine system communicate information from?
the brain to the body
what happens when hormones are released?
they have an effect on target organs such as the heart, liver or lungs
how are hormones produced?
in large quantities and have an immediate effect
what is cortisol been termed?
‘the stress hormone’ because it is secreted in higher levels during the body’s ‘fight or flight’ response to stress
EVOLUTION
what is evolutionary psychology?
a branch of the biological approach of psychology
what is applied to research on the structure of the human mind?
knowlegde and principles from theories of evolution
what do evolutionary explanation argue that?
some behaviours and characteristics are genetically determined
what happens if genetically determined behaviours are adaptive?
they will be naturally selected
what is natural selection?
the gradual process by which nature selects the forms most fit to survive and reproduce in a given environment
what is sexual selection?
the selection of characteristics that are cncerned with reproductive success
who are the selectors?
females, whilst males compete for her attention
2 strengths of the biological approach
- 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
2 weaknesses of the biological approach
- doesnt take into account the influence of people’s environment, their fmily, childhood experiences or their social situation. other approaches see this as being important factos in explaining behaviour
- using a biological explanation for negative behaviour can lead to individuals or groups avoiding taking personal or social responsibility for their behaviour
