Alice Nevard¹, Soazig Casteau¹, Ulrik Beierholm¹, Holger Wiese¹; ¹Durham University

Learning a new face can be described as gradual formation of a robust representation that supports recognition of an individual in novel contexts. Previous event-related potential (ERP) research has demonstrated that more negative amplitudes from approximately 200 ms onwards are associated with newly learnt faces compared to novel ones, suggesting a robust neural learning effect. The current study examines how representations of newly learnt identities are formed following a brief real-life interaction, compared to viewing novel matched (i.e. similar-looking) and unmatched (i.e. dissimilar) identities. Participants had a 10-minute conversation with one of four individuals they had not met previously. Participants then saw multiple ambient images with high within-person variability, of the “learnt”, an “unmatched” and a “matched” face while their EEG was recorded. N250 amplitudes (200-300 ms, occipito-temporal channels) were more negative for the learnt face compared to both the unmatched and matched identities, indicating the emergence of a distinct neural representation for the newly learnt face. Additionally, no differences were found between the matched and unmatched novel identities, indicating that both novel faces were similarly differentiated from the learnt identity. Furthermore, this ERP learning effect was carried over into later time windows showing sustained familiarity effects, and learning effects were generally stronger over the right hemisphere after 300 ms. Together these findings indicate that brief real-world interactions allow to establish robust neural representations that support the recognition of newly learnt faces – even in comparison to similar-looking novel identities.