AUTHOR=Cho Philip S. , Escoffier Nicolas , Mao Yinan , Ching April , Green Christopher , Jong Jonathan , Whitehouse Harvey TITLE=Groups and Emotional Arousal Mediate Neural Synchrony and Perceived Ritual Efficacy JOURNAL=Frontiers in Psychology VOLUME=Volume 9 - 2018 YEAR=2018 URL=https://www.frontiersin.org/journals/psychology/articles/10.3389/fpsyg.2018.02071 DOI=10.3389/fpsyg.2018.02071 ISSN=1664-1078 ABSTRACT=We present the first neurophysiological signatures showing distinctive effects of group social context and emotional arousal on cultural perceptions, such as the efficacy of religious rituals. EEG data were simultaneously recorded from ethnic Chinese religious believers in group and individual settings as they rated the perceived efficacy of low, medium, and high arousal spirit-medium rituals presented as video clips. Neural oscillatory patterns were then analyzed for these perceptual judgements, categorized as low, medium, and high efficacy. The results revealed distinct neural signatures and behavioral patterns between the experimental conditions. Arousal levels predicted ratings of ritual efficacy. Increased efficacy was marked by suppressed alpha and beta power, regardless of group or individual setting. In groups, efficacy ratings converged. Individual setting showed increased within-participant phase synchronization in alpha and beta bands, while group setting enhanced between-participant theta phase synchronization. This reflected group participants’ orientation towards a common perspective and social coordination. These findings suggest that co-presence in groups leads to a social-tuning effect supported by between-participant theta phase synchrony.