Early adaptation to repeated unfamiliar faces across viewpoint changes in the right hemisphere: Evidence from the N170 ERP component

Event-related potential (ERP) studies have shown that sensitivity to individual faces emerges as early as ∼160 ms in the human occipitotemporal cortex (N170). Here we tested whether this effect generalizes across changes in viewpoint. We recorded ERPs during an unfamiliar individual face adaptation paradigm. Participants were presented first with an adapting face (∼3000 ms) rotated 30° in depth, followed by a second face (200 ms) in a frontal view of either the same or a different identity. The N170 amplitude at right occipitotemporal sites to the second stimulus was reduced for repeated as compared to different faces. A bilateral adaptation effect emerged after 250 ms following stimulus onset. These observations indicate that individual face representations activated as early as 160 ms after stimulus onset in the right hemisphere show a substantial degree of generalization across viewpoints.