Symmetric faces are a sign of successful cognitive aging

Abstract

It has been proposed that a common cause underlies individual differences in bodily and cognitive decline in old age. No good marker forthis common cause has been identified to date. Here, fluctuating asymmetry (FA), an indicator of developmental stability that relates tointelligence differences in young adults, was measured from facial photographs of 216 surviving members of the Lothian Birth Cohort 1921at age 83 and related to their intelligence at ages 11, 79 and 83 years. FA at age 83 was unrelated to intelligence at ages 11 and 79 and tocognitive change between 11 and 79 years. It was, however, associated with intelligence and information processing efficiency at age 83 andwith cognitive change between 79 and 83 years. Significant results were limited to men, a result predicted by sex differences in life historytradeoffs and life expectancy. Results were stronger when directional asymmetries were corrected in facial FA measures. Thus, FA is acandidate marker for the common cause of differential senescence.