The relation between person identity nodes, familiarity judgment and biographical information. Evidence from two patients with right and left anterior temporal atrophy

The aim of this study consisted of using neuropsychological data obtained in two patients (VL and StG) showing a selective atrophy of the anterior parts of the right (VL) and left (StG) temporal lobes to check current cognitive models of familiar people identification. According to these models, information coming from modality-specific "face", "voice" and "name" recognition units converge into "Person Identity Nodes" (PINs) where familiarity feelings are generated and which provide a modality-free gateway to a unitary semantic system, where information about people is stored in an amodal format. Data obtained in patient VL (and to a lesser degree in StG) were at variance with this model because VL showed: (1) a very impaired familiarity for faces, contrasting with a spared familiarity for names, indicating that familiarity judgments are generated at the level of modality-specific recognition units and not at a supramodal PIN; (2) a prevalent impairment of person-specific information available from faces rather than from names also for people that (being recognized as familiar from both their face and their name) should be normally represented at the PINs level. This last finding is at variance with the hypothesis assuming that the PINs may provide a modality-free gateway to a unitary semantic system, where information about people is stored in an amodal format.