Event-related brain potentials differentiate priming and recognition to familiar and unfamiliar faces

Recent studies from our laboratory have resulted in the identification of an event-related potential (ERP) correlate of a visual memory process. This memory process is reflected by a reduction in the voltage of the visual memory potential (VMP) to repeated pictures of unfamiliar faces compared to novel pictures of faces. In the current experiment we used unfamiliar and famous faces in an identical repetition priming paradigm, while the subject differentially recognized famous from non-famous faces. Significant differences in response times were obtained between primed and unprimed familiar faces, but not between primed and unprimed unfamiliar faces. The VMP was reduced to primed unfamiliar faces and significantly diminished to primed familiar faces compared to unprimed stimuli. Priming was typically reflected by a reduction of the VMP at the occipito-temporal region, whereas recognition resulted in a diminution of the VMP at both the occipito-temporal region and at the frontal region. These data support the involvement of differential neural systems for priming and recognition of visual stimuli.