A preliminary EEG study on persuasive communication towards groupness.

Social neuroscience has acknowledged the role of persuasion but examined either the Persuader's or the Receiver's neural mechanisms. This study explored electrophysiological (EEG) correlates of Persuader and Receiver during a naturalistic persuasive interaction, in which Persuader aimed to convince Receiver that adopting a group decision-making orientation was the best solution to manage a group dynamic. EEG data - frequency bands: delta (0.5-3.5 Hz), theta (4-7.5 Hz), alpha (8-12.5 Hz), beta (13-30 Hz) and gamma (30.5-50 Hz) - were collected from 14 Persuaders and 14 Receivers. Findings indicated that the strategic efforts of Persuaders to enhance groupness are linked to activation in specific EEG bands (delta, theta and alpha) that distinguish them from Receivers. There is a significant distribution of these activations in the frontal areas of the Persuaders (especially, frontal right hemisphere for theta band), contrasting with the more temporal and posterior activations observed in Receivers (where the frontal areas are generally less activated). The study concludes that, under the same behavioral conditions in terms of group orientation, persuasive interaction shows specific EEG markers that connote the role of the Persuader characterized by greater attentional effort during the interaction.