Is fear contagious? | Popular Science

We’ve all felt it: heart racing, palms sweating, stomach clenching—the iron grip of fear. Whether it’s the sudden threat of an out-of-control vehicle or the nervous wait before a job interview, we all have felt fear’s sudden grip. But could fear actually be contagious?

“We are social creatures who learn from others,” says Arash Javanbakht, a psychologist at Wayne State University and author of Afraid: Understanding the Purpose of Fear and Harnessing the Power of Anxiety. Oftentimes, we learn what to fear from other people. So, short answer: Yes, if you’re around scared people, you’ll feel afraid, too.

Fear is a survival instinct

To understand fear, it’s important to recognize the context in which it developed. “Fear needs to be contagious,” says Javanbakht. “The fear system is primitive and developed mostly with physical threats” in mind. If one person fears a predator, others pay attention and react even if they don’t perceive the threat directly. Learning what to fear from others has helped humans survive.  

Sensing others’ fear activates the amygdala, the part of the brain that responds to threats. The amygdala then signals the hippocampus to activate the nervous system, releasing a surge of adrenaline that speeds up the heart and quickens breathing. It’s all part of your body’s fight-or-flight response, giving you a burst of energy to confront or escape threats. 

How fear is imitated

Humans naturally imitate each other. “Many emotions are social in nature,” says Jacek Debiec, a psychiatrist at Great Lakes Psychiatry and Psychotherapy. “We not only experience them, but also communicate and share them with others.” Copying emotions, like fear, is a fundamental part of the way we understand each other. 

Studies show humans can develop fear of an object simply by watching others get shocked by it. Even fearful faces, flashed too quickly for conscious recognition, can trigger activity in the amygdala, suggesting fear can spread subconsciously. These findings suggest that we can learn fear from others without direct experience of the situation or even conscious awareness. 

Other animals, like some rodents, also imitate fear. When rats hear the distress calls of other rats in pain, they freeze in fear. “Fear may be transmitted by many means,” says Debiec. “Humans rely heavily on vision and hearing. Other animals rely more on odors and auditory cues.”

Can people smell fear?

Animals often respond strongly to smell. When scared and injured, many creatures—from zebrafish to ants—release chemicals called pheromones. These olfactory alarm signals warn of potential dangers and trigger fear in other animals of the same species.

For years, scientists doubted humans could smell fear since we lack a functioning organ to detect pheromones. However, studies now show we can smell fear. When we do, our brain releases chemical signals (chemosignals) that activate the amygdala. 

In one experiment, researchers collected sweat from people about to skydive and those on a treadmill. Study participants then sniffed cotton pads containing the sweat samples. Brain scans revealed that those who smelled the skydivers’ sweat showed increased activity in their amygdala. In other words, people, perhaps subconsciously, could “catch” the skydivers’ fear.

How biology, empathy, and past experiences can shape our response to fear 

We all share the brain circuitry that makes fear contagious. But not everyone reacts in the same way due to genetics, past experiences, and empathy levels. Less empathetic people may feel mild fear when they’re around other people who are afraid. Whereas more empathetic individuals, when in the same situation, might feel fear more intensely. 

Those with relevant knowledge and experience might also feel less scared when others panic. If a wild snake has escaped in a zoo, an expert zoologist who knows that the snake isn’t actually dangerous won’t be affected by a panicking crowd.

Some people are also biologically more prone to feel fear when others are afraid. “Those who have been in catastrophes or wars, their children’s genes have changed to be more ready to be afraid,” says Javanbakht. Holocaust descendants, for instance, have a heightened sensitivity to danger and therefore might feel fear more often. Trauma alters how stress-related genes are expressed, influencing how they respond to fear and making holocaust descendants more alert to threats. 

Learning fear from others can give us a better chance of escaping physical dangers. But in daily life, we also fear situations that aren’t actually dangerous, like public speaking or a first date. Others may pick up on this fear, spreading your unease to your boss or crush.

So next time you go to a job interview or there’s turbulence on your flight, just remember—fear is catching. 

This story is part of Popular Science’s Ask Us Anything series, where we answer your most outlandish, mind-burning questions, from the ordinary to the off-the-wall. Have something you’ve always wanted to know? Ask us.

 

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