When a stranger becomes a friend: Measuring the neural correlates of real-world face familiarisation

Abstract

ABSTRACT Humans can readily and effortlessly learn new faces encountered in the social environment. As a face transitions from unfamiliar to familiar, the ability to generalize across different images of the same person increases substantially. Fast periodic visual stimulation and EEG (FPVS-EEG) was used to isolate identity-specific responses that generalize across different images of the same person from low-level visual processing and face-general processes that aren’t identity-specific. We observed these signals emerge and increase in magnitude as a group of strangers became lab mates (N=9). The neural response to an unfamiliar identity that remained unfamiliar did not change. Comparison of the response to the newly familiarised face to a highly overlearned face (the own-face) showed that this identity-specific signal was modulated by level of familiarity. The study presents the first examination of identity-specific processing changes as they occur in situ from normal, everyday face experience.