Belief shift status in moral reasoning: evidence from EEG hyperscanning and real-time dialogic framing

This study investigated the neurophysiological correlates of belief shift following interpersonal moral framing. Using electroencephalography (EEG) hyperscanning, dyads of participants engaged in real-time dialogic interactions centered on a morally salient professional dilemma. Participants initially evaluated moral justifications individually, participated in a structured exchange assuming complementary roles (Framer and Re-framer), and then re-evaluated the scenario. A Belief Shift Status Index, calculated from changes in emotional and cognitive ratings, classified participants into "change" and "no change" groups. EEG spectral analysis revealed significant differences between groups: individuals classified as "no change" exhibited higher beta-band activity over frontal regions and greater gamma-band activity in parieto-occipital areas compared to those classified as "change". Beta increases were associated with enhanced top-down cognitive control, whereas gamma activity reflected greater semantic integration and episodic simulation during moral reasoning. These findings demonstrate that distinct neurophysiological patterns support belief stability versus modification in socially framed moral contexts. By integrating a dynamic belief shift classification with real-time hyperscanning, this study provides new evidence on the cortical mechanisms supporting belief evaluation and adaptation during interpersonal communication.