An ERP study on pre-attentive processing of emotional faces in individuals with high social anhedonia.

Expression-related visual mismatch negativity (EMMN) is encoded by prediction errors associated with facial emotion changes. Previous studies have shown that patients with psychiatric disorders (e.g., schizophrenia and major depressive disorder) exhibit significantly reduced EMMNs. However, although social anhedonia is recognized as a transdiagnostic feature across psychiatric disorders, it remains unclear whether individuals with high social anhedonia (HSA) also display similar deficits. The present study aimed to explore the pre-attentive processing characteristics of unexpected facial emotions in individuals with HSA. Thirty-one participants with HSA and 31 participants with low social anhedonia (LSA) were recruited. The EMMN components elicited by happy and sad expressions in an oddball-control paradigm were analysed under three different time windows (70-140 ms, 180-270 ms, 280-360 ms) over six regions of interest. In comparison with the LSA group, the EMMN amplitudes elicited by emotional faces were lower in the HSA group in the 280-360 ms time window. In addition, the results showed that the decreased EMMN amplitudes in the 280-360 ms time window were significantly correlated with social anhedonia. Our study indicated decreased EMMN and its close relationship with social anhedonia in individuals with HSA, which promotes a deeper understanding of the psychophysiological mechanism of emotional face processing in individuals with social anhedonia.