Ch. 4 Biological Underpinnings of Personality Flashcards
Week 4 (29 cards)
What are twin studies?
a study examining twins raised apart or together, usu to explore whether characteristics are caused by genetics or the enviro.
How are twin studies useful?
a useful method for separating the effects of genetics and family enviro. if genetics is more NB then they should still be sim if raised apart, but if enviro is more NB then they should be diff. most find that genetics explains about half the variation in personality traits.
What are the limitations of twin studies?
the restriction of range problem; the fams enviros of separated twins’ adopted homes did not differ that much (ie both middle class). birth cohort problem; twin studies leave out culture bc in the same country and generation. also cant rule out confounding variables like being treated the same bc of their shared appearance. so theses studies capture variance within one culture and one time.
What are monozygotic twins?
identical twins sharing the same genetic profile.
What is a shared enviro?
the effects of growing up with the same parents, so same house, same family.
What is a nonshared enviro?
experiences not shared by siblings, such as friends, personal injuries, participating in diff activities.
What is percentage of variance?
explained by genetics and the enviro, refers to the variation among a group of ppl. ie 90% of the variance/difference in human height is determined by genetics.
How do genes and the enviro interact to shape personality traits?
enviros can influence genetic expression, the phenotype (actual behaviour and appearance) is only determined partially by the genotype (genes). gene-enviro interactions include epigenetic influences that can be passed down to future generations.
What is a genotype
an organisms genetic predisposition
What is a phenotype?
the observable characteristics of an organism resulting from the interaction of the genotype and the enviro. ie how the genotype actually is expressed/appears in the organism.
What is gene-environment interaction?
when genetics and enviro work together to shape personality. ie genetic predispositions can influence the enviro, and enviros can influence if a genetic predisposition is expressed. ppl also seek out enviros that suit them.
What is epigenetics?
the idea that some enviros can influence how much genetics will matter. ie differences in gene expression caused by the enviro.
What is gene expression?
how much a gene influences traits or outcomes.
How do personality traits appear in the brain?
personality influences physiological reactions, including the reactivity to stimuli (more pronounced among introverts), and the activity of brain regions.
What personality trait is linked to the frontal lobe?
frontal lobe makes plans and considers decisions, helps regulate emotions and behaviour. if damaged self control is impaired, to more impulsive/low conscientiousness.
What personality trait is linked to the amygdala?
responsible for processing reactions to fear. ppl high in neuroticism have stronger responses in the amygdala.
What is discrepancy detection?
noticing things that are unusual, unclear, or different in the environment. ppl high in neuroticism show stronger responses in areas associated with this.
What is morningness-eveningness?
whether you’re a morning person or evening person. can be influenced by personality ie. morning ppl usu higher in conscientiousness and agreeableness but lower in extraversion, neuroticism, and openness.
How does evolutionary psych explain human tendencies?
suggests that ppl will behave in ways that max both their survival and reproduction. argues that human psychological processes evolved to promote survival and reproduction. ie humans inherent need to belong. individual differences like personality might have evolved to adapt to different enviros.
What are the challenges with the evolutionary psych approach?
difficult/impossible to prove that preferences are caused by evolution.
How do hormones influence behaviour among women and men?
men respond differently to women depending if theyre in their fertile phase of their cycle. women express different mate differences based on hormonal variations. T is linked to aggressive behaviour, and mens and womens experiences can change their T lvls.
What is the 2D:4D ratio?
the length of someones index finger divided by the length of their ring finger. a low ratio is linked to high prenatal T.
What is genetics?
the DNA from ones bio mother and father.
What is biology?
everything that appears in the body and brain, wtv its origin (genetic or environmental).
