Cloninger's Seven Personality Dimensions and IQ

Overlap between Genetic and Environmental Factors in a Twin Study

Abstract

Using a behavioral genetic approach, we examined the association between Cloninger’s Temperament and Character Inventory (TCI) and IQ in terms of underlying genetic and environmental etiological overlap. Using the TCI personality dimensions (4 temperaments and 3 character traits) and IQ data for 199 pairs of adolescent and young adult twins, we found a genetic negative correlation between one of the character traits (self-transcendence) and IQ. In contrast, we did not find significant environmental correlations between any of the personality dimensions and IQ. These results suggest that contributions from the same genetic factor operate on both self-transcendence and IQ.