Person-Environment Fit Underlying Cognition Partially Explains Increasing Heritability across the Lifespan

Using cognitive ability data collected in 860 twins (513 females, Mage = 70.36, SD = 10.09) in the Swedish Adoption/Twin Study of Aging, genetic simplex models were used to test person-environment effects in older adulthood. Results suggest that person-environment covariance partly explains why heritability of cognitive ability increases with age.