Recognizing faces is an important social skill, but not all of us are equally good at it. Some people are unable to recognize even their closest friends (a condition called prosopagnosia), while others have a near-photographic memory for large numbers of faces. Now a twin study by collaborators at MIT and in Beijing shows that face recognition is heritable, and that it is inherited separately from general intelligence or IQ.

This finding plays into a long-standing debate on the nature of mind and intelligence. The prevailing generalist theory, upon which the concept of IQ is based, holds that if people are smart in one area they tend to be smart in other areas, so if you are good in math you are also more likely to be good at literature and history. IQ is strongly influenced by heredity, suggesting the existence of “generalist genes” for cognition.

Yet some cognitive abilities seem distinct from overall IQ, as happens when a person who is brilliant with numbers or music is tone-deaf socially or linguistically. Also, many specialized cognitive skills, including recognizing faces, appear to be localized to specialized brain regions. Such evidence supports a modularity hypothesis, in which the mind is like a Swiss Army knife — a general-purpose tool with special-purpose devices.

Journal Reference:

1. Zhu et al. Heritability of the Specific Cognitive Ability of Face Perception. Current Biology, 2010; DOI: 10.1016/j.cub.2009.11.067