In the qualifying matches for the FIFA World Cup of 1970, Honduras won the first match in its capital Tegucigalpa, and El Salvador won the second in San Salvador. Violence broke out at both matches between the visiting and home fans, and thousands of Salvadorans left Honduras after their victory in the second match, avoiding persecution. At the time, there were historical tensions between Honduras and El Salvador that escalated within the matches.

This soccer war isn’t the only example of an extreme reaction from fans. Hooligans, ultras or barras bravas — terms used to describe football fan associations in Latin America — often commit violence, property damage and even murder in supposed support of their teams on the field.

Francisco Zamorano, a medical biologist at the University of San Sebastian in Conception, Chile and the Clinica Alemana, wanted to understand why some fans experienced these extreme reactions, and discovered it has a lot to do with the brain.

Why do Sports Fans Feel so Connected to the Teams?

Zamorano knows what it feels like to go crazy for a sports team. While growing up in an underprivileged community in Chile, he was a fan of Colo-Colo, a soccer team based in Greater Santiago that plays in the Chilean premier division. Colo-Colo’s arch rival is the Universidad de Chile club — also based in Santiago.

“When Colo-Colo lost against Universidad de Chile, I’d feel a sadness for several days,” Zamorano says — something he wouldn’t experience when they lost to other teams. Conversely, when Colo-Colo won, he’d experience a feeling of well-being.

“[Colo-Colo] is very important for my identity as a person,” Zamorano says, adding that super fans can experience a vicarious sense of winning and loss as if they were the players on the field. “Football can give you some kind of value that you don’t have.”

When Zamorano began his research, he used an MRI to learn more about how the brain of an extreme fan worked. He used the machine on himself and replayed old matches between Colo-Colo and Universidad de Chile out of curiosity.

Zamorano discovered that certain parts of his brain were activated only when Colo-Colo scored for or were scored against Universidad de Chile. Conversely, when other teams scored against his club, he didn’t feel the same sense of loss.

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What Does the Brain Look Like for a Super Fan?

To expand the study, Zamorano added 62 participants to his research that is published in F1000Research. The MRI scans revealed that in super fans, some parts of the brain become more active while others become less active. When the teams of super fans scored goals on their arch rivals, the reward sections of fans’ brains were activated.

Conversely, when scored against, the mentalizing network — regions of the brain that help us think of ourselves and others — was sometimes activated in super fans. When this section of the brain is more involved, it usually means that fans will get more introspective — perhaps to cope with the sadness or negative feelings they experience.

But when arch rivals scored against their team, super fans also experienced a deactivation of the dorsal anterior cingulate cortex (dACC). This is an area that connects your feelings and emotions with the rest of your brain. This is important because the dACC regulates our ability to not act on our emotions — it disconnects feelings with rationalizing areas in the brain.

Perhaps this is what happens with hooligans, who have “a notorious lack of self-control” when they become violent, Zamorano says. Their dACC may be deactivated, which means they are more prone to this kind of behavior.

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What Is Our Connection to Sports?

For Zamorano, the issue is compounded in sports because they can become so wrapped up in people’s identities. Sports teams can often serve as a symbol of nationalism, or civic pride.

The combination of lacking the right mental tools to deal with loss and being around others experiencing the same thing can lead to larger problems with extreme violence in sports fans after and during games.

“It produces these echo chambers that are very gratifying,” Zamorano says.

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