Extreme ingroup and outgroup perspectives counter-intuitively impact intergroup polarisation at the level of neural oscillations

• DOI: 10.1016/j.cortex.2024.12.020
• Publication Date: 2025-01-11T16:01:01Z
• Authors: Annika Kluge; Jonathan Levy
• Keywords: Outgroup; Ingroups and outgroups; In-group favoritism

A powerful example of affective polarisation occurred between vaccine-supporters and -opposers when vaccinations were implemented to counter the recent global pandemic. In this social neuroscience study, we scanned 121 using magnetoencephalography evaluate three levels polarisation: explicit, implicit, neural - then test whether exposing people extreme ingroup perspectives (following paradoxical thinking principles) or outgroup can modulate those vaccinated unvaccinated individuals. We show that a proxy for intergroup polarisation, expressed as late prefrontal beta rhythm suppression, detect subtle changes in polarisation. More specifically, find (i.e., pro-vaccination) viewpoints leads decrease Conversely, exposure anti-vaccination) narratives increases which turn predicts positive affect towards vaccine opposers almost one year later. Altogether, results although it may seem intuitive expose counter-arguments perspectives) change their opinions, such an approach backlash increase instead. However, subtler methods intervention attitude have desired effects reduce