The neural basis of facial resemblance

Humans respond favourably to self-resembling faces. Self-facial resemblance is a mechanism for self-referent phenotypic matching by which humans can differentiate genetic kin from other members of a social group. To better understand how the brain makes discriminations between kin and non-kin, we investigated the neural correlates of self-resemblance in faces that were transformed along the dimensions of race and sex. We show that anterior cingulate and medial prefrontal cortex were associated with discrimination between closely resembling racially similar same-sex faces, whereas lower-level visual regions were involved in discriminating self-reference when faces are more characteristically distinct. These findings extend previous literature, which has shown posterior medial cortical involvement in self-reference, by demonstrating a clear anterior–posterior differentiation based on closeness of self-referent match. Our findings suggest the evolution of anterior–posterior neural organization associated with making self-other judgements pertinent to kin recognition.