PSY230H5 Lecture Notes - Lecture 12: Serotonin Transporter, Twin Study, Multiple Dispatch
Document Summary
There have been dozens of twin studies of personality traits (mainly e and n, but also o,a and c) Typical textbook estimate of heritability for big 5 is 40-40% One multi-method study found heritability estimates around 70% Estimates for shared environment are typically close to 0% Evidence suggests that shared environment has a stronger contribution on personality in studies of children than in studies of adults. This finding suggests that environment contributes to personality, but does not have lasting effects. Possible to examine the contribution of genes to stability of personality. Typical finding: genes contribute to stability, environment contributes to change. Example: 80% heritability of stable disposition to be cheerful over a 10- year period (lykken and tellegen, 1996) Shared environment (parents) has a weak influence on personality traits (big 5) Shared environment has an influence on some behaviours (eg. smoking) Shared environment effects tend to be stronger for children than for adults.