The Influence of Shared Attention and Friendship on Emotional Processing: A Behavioral and EEG Hyperscanning Study

Shared attention facilitates interpersonal emotional sharing, yet the neural mechanisms modulated by interpersonal relationships, emotional valence, and visual consistency remain unclear.

This study recruited 39 dyads (22 friend dyads, 17 stranger dyads) who viewed neutral, positive, and negative images under shared or non-shared attention while image consistency between partners was manipulated. Emotional ratings and electroencephalography (EEG) inter-brain synchrony were recorded.

Behaviorally, shared attention shifted emotional processing toward positivity, especially in friend dyads. EEG hyperscanning revealed that shared attention was associated with increased beta and theta band inter-brain synchrony in the prefrontal cortex for friends, but decreased synchrony for strangers, and alpha band synchrony decreased with shared attention when viewing consistent images.

These findings reveal band-specific neural mechanisms through which shared attention modulates emotion across friendship, offering new insights into emotional regulation in social interactions.