The personality–intelligence interface: insights from an ageing cohort

Recent attempts have been made to provide a theoretical model that accounts for the findings linking intelligence and personality, and it has been suggested longitudinal research is necessary to empirically evaluate this (Chamorro-Premuzic & Furnham, 2004). The current study uses longitudinally collected data on almost 500 people to investigate the link between intelligence (assessed in the same individuals at ages 11 and 79) and the non-cognitive traits of typical intellectual engagement (TIE) and Big-Five personality (measured in late adulthood). Intelligence in childhood and late adulthood was significantly related to the personality factors Emotional Stability and Intellect (r = 0.11–0.32, p < 0.05). When initial ability (age-11 IQ) was controlled for, the association of age-79 IQ and Intellect fell to almost zero (r = 0.02, ns), whereas the significant Emotional Stability correlation was largely unaffected. TIE associated with IQ at both ages (age-11 r = 0.21 and age-79 r = 0.13, p < 0.01); however, controlling for prior ability removed the TIE and age 79-IQ association (r = −0.01, ns). Structural equation modelling of these data suggested no direct link between contemporaneous Intellect, TIE and late adulthood ability, indicating that they are related through the lifelong stable trait of intelligence.