biological psychology Flashcards
name three assumptions of the biological approach
- behaviour is determined by genes
- behaviour is determined by the brain
- behaviour is determined by hormones
explain (using example) how behaviour is determined by the brain
the PFC is responsible for decision making and personality. damage to this area of the brain can lead to aggression - as shown by phineas gage
explain (using example) how behaviour is determined by genes
for example female (XX) have more feminine behaviours and men (XY) have more masculine behaviours like aggression
explain (using example) how behaviour is determined by hormones
oestrogen makes women more nurturing and testosterone makes men more aggressive for example in sports.
what does nature conclude
behaviour is determined by biology
what does nurture conclude
behaviour is determined by our environment
genotype + environment
phenotype (behaviour)
what are epigenetics
certain genes can be turned off and on by the environment
what are MZ and DZ twins
MZ (identical) have 100% shared genetics where one egg has split
DZ (fraternal) have 50% shared genetics where there is 2 eggs.
what is a concordance rate
degree of similarity between people
concordance rate 1
complete same
concordance rate 0
completely different
if MZ twins have higher concordance rates than DZ twins would we conclude nature or nurture
nature
2 strengths of twin studies
- generates large volumes of data (eg kendler et al used 1588 twins)
- suggests genetic components may be involved in a wide range of psychological phenomena (eg hettema et al found that MZ twins are more similar than DZ twins in their tendency to be classically conditioned to fearful stimuli)
3 weaknesses of twin studies
- MZ twins are often treated more similarly than DZ twins (t/f harder to distinguish if characteristics are due to nature or nurture)
- seperated twins are often brought up in similar environments (same t/f as above)
- lacks pop v (not everyone is a twin)
what is my twin study
brengden et al
what is my contempary study for biological psych
brengden et al
aim of brengden et al
investigate if social aggression could be caused by genes or the environement. see if social and physical aggression had the same cause and if one type of aggression led to another.
participants of brengden et al
234 twin pairs from the Quebec Twin Study - data gathered between ages 5 months to 6 years
brengden et al procedure
- teacher rankings
- peer rankings
in brengden et al what did teacher rankings consist of
agreement with statements based on social (eg to what extent does this child try to make other children dislike a child) and physical (eg to what extent does this child get into fights) aggression using 3 point agreement scales taken from the PSBS and direct and indirect aggression scales.
in brengden et al what did peer rankings consist of
giving children a booklet with pictures of children from the class, then asked to circle three children in the class who matched each description the best. eg “tells others not to play with another child” (social) or “gets into fights” (physical)
brengden et al finsings
- teachers found boys more physically aggressive and girls more socially
- peers found boys more aggressive for both
- MZ correlation almost twice as high as same sex DZ for physical aggression
- MZ and same sex DZ rankings for social were similar
brengden et al conclusion
strong genetic component to physical aggression but not social, more likely due to environmental effects. children who were physically aggressive were more likely to be socially aggressive (interaction between genes and the environment) . as children grow they become more socially aggressive as they learn to express themselves.
4 strengths of brengden et al
- eco v (in school)
- inter rate relaibility (peer and teacher)
- practical apps (phys aggression could be an early indicator of later life aggression)
- standardised procedure (same statements)
4 weaknesses of brengden et al
- pop v (quebec and 6 y/o)
- cause and effect (no genetic testing to check if MZ are MZ)
- mundane realism
- protection from harm (ranking of aggression)
if birth parents have higher concordance rates than adoptive parent what do we conclude
nature
what is my adoption study
leve et al
aim of leve et al
to look at specific environmental issues related to parenting and family processes that interact with genetic factors on a child. to look at the adoptive parent and adopted child to see when and why genes and environment interactions occur between them.
participants of leve et al
360 adoptive triads (adopted within three moths of birth), recruitment by means of opt out.
leve et al procedure
- questionairres (in person or via telephone)
- observations of adoptive family
- salivary DNA collected
- children given tempermant tasks and parent child interaction tasks
- teachers completed questionairres.
what did the questionairres ask in leve et al
intelligence testing, anti-social personality, conduct disorder
what did the interviews ask in leve et al
well being and childs daily behaviour
leve et al findings
if bio parent had high anxiety or depression child became frustrated easily, but if adoptive parent didn’t the child was able to let it go however if the adoptive parent did have high anxiety or depression the child was unable to let it go
leve et al conclusion
genetic factors in adoptive child can interact with environmental factors from adoptive family to produce behviour, and if such things are known about intervention can be used to alleviate this issue.
4 strengths of leve et al
- right to withdraw ( opt out )
- practical apps ( prevent long term depression )
-mundane realism - standardised procedure
4 weaknesses of leve et al
- pop v (usa)
- protection from harm (frustrating task)
-resarcher bias (in person observations) - rapport (telephone questionairres)
what are dominant genes
genes that always lead to a certain characteristic (eg brown hair)
what are recessive genes
genes that need more than one copy to produce a characteristic (eg blonde hair)
what does the CNS consist of
brain and spinal cord
describe synaptic transimission
- nerve impulse travels down axon (builds up energy)
- if it builds up enough energy it will depolarize the presynaptic neuron
- vessicles are stimulated releasing neurotransmitters
- neurotransmitters find the right receptors and once another are filled up the message is passed on
- left over neurotransmitters are take up via the reuptake pump