Neural dynamics of monetary and social reward processing in social anhedonia.

Being characterized by reduced pleasure from social interaction, social anhedonia constitutes a transdiagnostic marker for various psychiatric disorders. However, the neural portrait of social anhedonia remains elusive because of heterogeneities of reward type and reward dynamics in previous studies. The present event-related potential (ERP) study investigated neural dynamics in response to monetary and social rewards in social anhedonia. ERP responses were examined when a high social anhedonia (HSA, N = 23) group and a low social anhedonia (LSA, N = 26) group were anticipating and consuming social and monetary rewards. During the anticipatory phase, the stimulus-preceding negativity was increased for monetary compared to social rewards in the LSA group but not the HSA group. During the consummatory phase, the reward positivity was increased for monetary relative to social rewards, which was found for the LSA group but not the HSA group. These results could result from an increased relevance of social rewards or a general decline in affective responding due to a potential association between social anhedonia and depression. Our findings provide preliminary evidence for neural aberrations of the reward system in social anhedonia, which is contingent upon reward type and reward dynamics.