Persistent task-specific impairment of holistic face processing in acquired prosopagnosia.

Face recognition deficits observed in Acquired Prosopagnosia are typically associated with impaired holistic processing. Nonetheless, whether this deficit is task-dependent, face-specific, and persistent over time has been under investigated. The present study examined the role of holistic processing in a case of acquired prosopagnosia (Patient DS). Patient DS, along with several neurotypical participants, completed the three standard measures of holistic face processing: the face inversion, part-whole, and composite face tasks, as well as a measure of non-face global processing: the Navon task. Our single-case analyses indicated that, compared to neurotypical participants, DS showed (1) impaired inversion effects, but (2) comparable part-whole and composite face effects, as well as (3) comparable global precedence effect in the Navon task. Interestingly, the same pattern of preserved and impaired holistic processing was observed in a second evaluation of DS four years later. While these findings suggest that holistic processing deficits in Acquired Prosopagnosia may be task-specific and persist over time-pointing toward the potential chronicity of the impairment-they should be interpreted with caution, given the floor effects and the single-case design.