fMRI exams of soccer fans' brains offer clues to the cause of fanaticism

Functional MRI (fMRI) reveals how soccer fans' brains respond when their team scores against rival teams -- and may offer clues as to what causes fanaticism, researchers have reported.

The findings illuminate the phenomena of "in-group bonding and reinforcement of social identity," wrote a team led by Francisco Zamorano, PhD, of the Universidad San Sebastián in Santiago, Chile. The results were published November 11 in Radiology.

"Soccer fandom provides a high-ecological-validity model of fanaticism with quantifiable life consequences for health and collective behavior," Zamorano said in an RSNA statement.

Much research has been conducted regarding the effects of social connections on the brain, but "neurobiological mechanisms of social identity in competitive settings are unclear," the group explained. To address this gap, Zamorano and colleagues investigated "the brain mechanisms associated with emotional responses in soccer fans to their teams' victories and losses."

Their study included 61 healthy male soccer fans between the ages of 20 and 45 who underwent fMRI. The men were classified as spectators, fans, or fanatics via the Football Supporters Fanaticism Scale, a 13-item scoring system that measures disposition to violence and sense of group belonging, with higher scores suggesting more extreme fanaticism.

The researchers examined any changes in brain blood flow in the participants while they watched 63 goal sequences from matches involving their favorite team, a rival, or a neutral team. They performed whole-brain analysis to compare brain responses when the men viewed their favorite team scoring against an archrival (i.e., significant victory) versus when the archrival scored against their team (i.e., significant defeat).

Overall, they found that "higher activation in the reward system regions occurred when participants' teams scored against rivals versus nonrivals, suggesting in-group bonding and social identity reinforcement" -- results that could help event planners develop communication, crowd management, and violence prevention strategies, they suggested. They also noted that soccer fandom offers an "ethical, high-validity proxy to time-lock these processes in the brain and to test interventions … that translate to politics, sectarianism and digital tribalism."

"Studying fanaticism matters because it reveals generalizable neural mechanisms that can scale from stadium passion to polarization, violence, and population-level public-health harm," Zamorano said.  

The research "represents a meaningful step toward understanding how passion, identity, and behavior connect within the brain, opening a door to future studies and broader conversations about how collective emotions can shape society," wrote Michael Lev, MD, and Otto Rapalino, MD, both of Massachusetts General Hospital in Boston, in an accompanying editorial.

"[The] study by Zamorano et al vividly demonstrates how sports tap into core human neural systems," they wrote. "Wins trigger reward circuits, losses reduce control, and fanaticism amplifies both these effects. By drawing parallels between football fandom and political and religious fervor, the authors show how neuroimaging can help reveal the brain's role in shaping social bonds and conflict, especially relevant in this time of increasingly deep divisions between different societal subgroups."

The complete work can be found here.