Nicholas G. Shakeshaft and Robert Plomin (2015)
Diverse cognitive abilities have typically been found to intercorrelate highly and to be strongly influenced by genetics. Recent twin studies have suggested that the ability to recognize human faces is an exception: it is similarly highly heritable, but largely uncorrelated with other abilities. However, assessing genetic relationships—the degree to which traits are influenced by the same genes—requires very large samples, which have not previously been available. This study, using data from more than 2,000 twins, shows for the first time, to our knowledge, that the genetic influences on face recognition are almost entirely unique. This finding provides strong support for the view that face recognition is “special” and may ultimately illuminate the nature of cognitive abilities in general.
Specific cognitive abilities in diverse domains are typically found to be highly heritable and substantially correlated with general cognitive ability (g), both phenotypically and genetically. Recent twin studies have found the ability to memorize and recognize faces to be an exception, being similarly heritable but phenotypically substantially uncorrelated both with g and with general object recognition. However, the genetic relationships between face recognition and other abilities (the extent to which they share a common genetic etiology) cannot be determined from phenotypic associations. In this, to our knowledge, first study of the genetic associations between face recognition and other domains, 2,000 18- and 19-year-old United Kingdom twins completed tests assessing their face recognition, object recognition, and general cognitive abilities. Results confirmed the substantial heritability of face recognition (61%), and multivariate genetic analyses found that most of this genetic influence is unique and not shared with other cognitive abilities.