False recognition and misidentification of faces following right hemisphere damage.

We report two patients who, following massive damage to the right hemisphere, showed a striking tendency for false recognition and misidentification of faces. Neuropsychological investigations revealed that excessive reliance on a feature-based left hemisphere strategy in face processing, combined with an inability to evaluate critically the output generated by the dysfunctional face recognition system, played a major role in the recognition errors and misidentifications. Our findings suggest that the feature based left hemisphere face recognition system is potentially error-prone, presumably because component facial features are likely to be shared among several different individuals, and that reliable recognition and identification of faces is critically dependent upon the efficient processing of configurational facial information by the right hemisphere. We propose further that decision making and monitoring functions relevant to the operations of the face recognition system are primarily lateralized to the right frontal lobe.