Is There a Time to Recognise Faces? Early ERP Correlates of Chronotype and Time-of-Day Effects on Face Recognition

Although face recognition is a pervasive and important ability in daily life, recognition of unfamiliar faces is difficult and highly error prone. The present study aimed to understand how chronotype and time-of-day (TOD) influence early electrophysiological activity associated with the recognition of faces. Twenty-seven participants (15 morning-types and 12 evening-types) performed two modified sequential versions of the Glasgow Face Matching Task at their peak and non-peak times (7:30 am and 7:30 pm), while their EEG was recorded. The task consisted in the presentation of 80 sequential pairs of faces, and participants were required to indicate whether the second face of each pair was the same or different from the first face. Results indicated a significant chronotype x TOD interaction on the P100 component, with morning-types registering higher amplitudes in the evening session, compared to the morning session. A non-significant opposite pattern was observed in evening types. Response accuracy was strongly positively correlated with P100 amplitudes. No significant differences were observed for the N170 component, nor on behavioural performance. These results suggest an early visual attentional asynchrony effect.