Differential responses to group and individual emotional voices: a behavioral and ERP study

Human beings live in social groups, and processing group emotions is crucial for interacting with and understanding others' behaviors and feelings. This study investigated the cognitive and neural mechanisms of processing group versus individual emotional voices within the auditory modality. We examined ERP responses of 34 participants to group and individual voices across three emotional valences (negative, neutral, positive). Behavioral results revealed a significant interaction: group voices yielded shorter reaction times for neutral and positive emotions but longer for negative ones, alongside more positive overall emotional reactions. Electrophysiologically, group voices elicited more positive N1 and larger P2 amplitudes, with shorter latencies. More specifically, for negative and positive voices, group voices elicited larger P2 amplitudes than individual voices, while no significant difference between group and individual voices emerged for neutral voices. Furthermore, P2 amplitudes elicited by group voices were negatively correlated with participants' trait cognitive empathy. These results suggest that group voices elicit stronger early neural responses driven by an interplay of acoustic and social salience. Importantly, rather than demonstrating a direct empathy-specific neural mechanism, the observed negative correlation suggests that trait empathy may play a role in modulating the early sensory detection and attentional processing of complex, emotional group empathy.