genes and behaviour Flashcards
(12 cards)
what are the 3 types of studies?
- genes and behaviour
- genetic simularities + twin + kinship
3.evolutionary exploitation for behaviour
What are the 6 ethical considerations? and what do they stand for?
1.Informed consent
2.Protection from harm
3.Anonymity and confidentiality
4.Withdrawal from participation
5.Deception
6.Debriefing
adobtion studie, name one?
Scarr and Weinberg (1983)—the Transracial Adoption Study
Aim. To investigate environmental malleability of intelligence.
Participants. This study looked at 101 adoptive families who had both biological and adopted children. Some of the adopted children were black and some white. Some children were adopted in the first 12 months of life and some were adopted later. The study took place in Minnesota.
It needs to be understood that back at the time when the study was conducted, in Minnesota being black meant, on average, coming from a poorer socio-economic status background and being less educated.
Procedure. All children were assessed on IQ and school achievement tests. Correlations were calculated between the IQ of children and their parents (both adoptive and biological).
Results. The table shows the results of comparing IQ in various subgroups.
As can be seen from the table, black children placed in white families saw a substantial increase in their IQ.
If they were adopted in the first year of life, they achieved the same level as adopted white children (although they had experienced a year of deprivation in the orphanage).
adobtion studie method?
Method. Adoption study.
genetic similarities: kinship study? … et al 2009?
a really interesting study by Natsuaki et al. (2009), the researchers compared 390 sibling pairs (780 participants), including MZ, DZ, full, half and genetically unrelated siblings (e.g. step-siblings).
This study investigated the prospective links between sibling aggression and the development of externalizing problems
The kids were measured for “externalizing problems.” These are examples of antisocial behaviours that are directed towards the external environment (e.g. towards others). Examples of externalizing problems include physical aggression, vandalism and stealing.
The table shows the results and how similar the sibling pairs of various genetic relatedness were in terms of externalized antisocial problems.
The table shows the results and how similar the sibling pairs of various genetic relatedness were in terms of externalized antisocial problems.
You can see that MZ twins were most similar, followed by DZ and so on (the higher the correlation score the more similar the twins in their rates of externalized antisocial behaviour). Interestingly, unrelated siblings scored higher than full siblings, but a further statistical analysis found that these results were not statistically significant.
One really interesting finding from this study was that when they controlled for other factors, they found that the behaviour of one’s sibling has an effect on behaviour. This has been called “deviancy training” (a type of social learning) and while the effect was small, it could be an important consideration in explaining behaviour - genes can affect behaviour, but the environmental factor of how siblings interact with one-another on a day-to-day basis that can have an impact on behaviour.
the method used in Caspi et al 2003 study?
Method. A longitudinal study. Genetic mapping was used to divide participants into three groups: – both short alleles of 5-HTT (s/s) – one short allele and one long allele (s/l) – both long alleles (l/l)
5-HTT gene has 3 combinations… what are they?
2x long
1x long 1x short
2x short
what is 5-HTT?
The serotonin transporter protein (5-HTT/SLC6A4) transports the neurotransmitter serotonin from synapses to presynaptic neurons.
what is a gene ?
its a nucleus and inside every nucleus are chromosomes and all chromosomes are made of DNA, molecules that contain genetic information called genes.
evolutionary explanation?
We have evolved to behave in ways that will increase the chances of survival (and thus passing on our genes).
one evolutionary explanation study?
caspie et al 2003
the evolutionary explanations method?
Convenience (opportunity) sampling.
We have evolved to behave in ways that will increase the chances of survival (and thus passing on our genes). The genetics that are passed on will influence our physiology in a way that promotes the adaptive behaviour.
