Telling one face from another: electrocortical correlates of facial characteristics among individual female faces.

Research investigating the neural correlates of face processing has emphasized differences in neural activity when participants view faces versus other stimulus categories (e.g., houses). Much less is known about the neural mechanisms underlying the discrimination among individual faces. Using a large number of female faces, here we show that the amplitude of the face-sensitive N170 electrocortical component is related to a range of facial characteristics. The right N170 amplitude was related to eye color and face width. The left N170 amplitude was related to eye shape and face proportions, suggesting a functional dissociation between hemispheres. In contrast, the amplitude of the P100 and N250 components was largely unaffected by these facial characteristics. Consistent with recent findings in non-human primates, we identify for the first time evidence of human electrocortical brain potentials that are sensitive to variations in specific facial characteristics, a prerequisite for recognizing the identity of individual faces.