In our study, which has just been published in PNAS, we show that fire-walkers, family members, and friends share heart rates through an experience of a collective ritual. We wired up participants and spectators with heart monitors at an annual fire-walking ritual in San Pedro Manrique, Spain, to try and quantify the social connectedness that underlies community rituals. Using a sophisticated mathematical technique, we determined that family members or close friends were uniquely synchronized to changes in fire-walkers’ heart rates throughout the ceremony. The pattern of synchrony differed from non-related onlookers. The technique distinguishes the changes in heart rhythms and adrenaline surges one might experience as an ordinary onlooker, from onlookers who share emotional bonds with those who walk barefoot across hot coals. What is distinguished, are the shared changes in cardiac activity signifying the individuals’ shared emotional experience. Firewalkers and their spectating loved ones, the researchers report, exhibit the same patterns throughout the ritual. Individuals who share emotional synchrony thus also share physiological synchrony. The investigation demonstrates a new method for quantifying the shared experience of collective rituals in human physiology.
This study was conducted by an interdisciplinary team of researchers from MINDLab and Center of Functionally Integrative Neuroscience, Aarhus University. The authors include an biomedical engineer, Ivana Konvalinka, an anthropologist, Dimitris Xygalatas, three researchers from the study of religion, Joseph Bulbulia, Uffe Schjødt, and Else-Marie Jegindø, two psychologists, Sebastian Wallot and Guy Van Orden, and Andreas Roepstorff, co-director of MINDLab.
The implications of our findings could perhaps be extended to various other forms of collective action, such as corporate team-building, affiliation in sports, public riots, warfare, and so on. Shared arousal might then be either one mechanism driving these collective actions, or a mechanism that emerges from the collective actions themselves.
See article in The New Your Times: Hearts Beat as One in a Daring Ritual