Emotional Contagion: How humans catch and spread feelings without ever knowing

While some people think they are perpetually cool, calm, and collected, they're not. At least, not all the time.

Across the board, human beings are a roller coaster of emotions, feelings, and moods. According to 25 years of data, these emotions spread like wildfire person to person. Often, they influence a group or organization's collective mood in positive or negative ways.

This social phenomenon, called "emotional contagion," permeates all human interactions, influencing not only how people feel, but how they think and behave. Emotional contagion is constant and pervasive, yet most of the time we have no idea it's going on.

Sigal Barsade, a professor at the University of Pennsylvania Wharton School of Business, has studied emotional contagion for more than 25 years.

As humans, emotional contagion is one of our "primary delivery systems for emotion," Barsade tells Inverse. "Emotional contagion is the act of person A feeling the emotions that person B is showing, to some extent."

This week, Inverse explores how to understand emotional contagion, prevent your bad moods from negatively impacting others, and leverage the concept to become a more positive force in the world.

"By understanding this phenomenon, that is a form of inoculation against emotional contagion," Barsade says. "It's the first step."

I’m Ali Pattillo and this is Strategy, a series packed with actionable tips to help you make the most out of your life, career, and finances.

Catching feelings — Years before Barsade completed her organizational psychology training, a common office scenario spurred her to investigate how emotions spread.

She was working in an open-office layout close to a particularly negative coworker — the sort who seemed to dampen the entire team's mood whenever she was around. The negative atmosphere didn't arise from this coworker’s yelling, or even what she said, Barsade recalls. Rather, it was her subtle facial expressions, verbal delivery, and general energy.

When the coworker left for a week of vacation, the entire office mood shifted for the better. Barsade was dumbfounded by how powerful this one individual's emotional state was on the group. She’s spent more than two decades seeking to understand it.

Emotional contagion is defined by researchers as "a process in which a person or group influences the emotions or behavior of another person or group through the conscious or unconscious induction of emotion states and behavioral attitudes.”

The phenomenon operates via two main pathways: behavioral mimicry and physiological feedback.

“Not only do we mimic the feelings of others; we actually start to feel them ourselves.”

"Not only do we mimic the feelings of others; we actually start to feel them ourselves," Barsade says. When someone is happy or angry around us, we inadvertently mirror their emotion.

This response is subconscious and hardwired, stemming from a basic evolutionary behavior. As babies, we mimic our caretakers, and we continue to do this to varying degrees throughout our lives.

On top of this initial mimicry, our facial muscles linked to those emotions dictate blood flow throughout our brain and body. This theory is called facial efference, and it’s a process that makes us feel the sensations of an emotion, like a flushed face, or a pit in our stomach.

Oftentimes, people aren’t aware that they've caught someone else’s feelings, instead misattributing them to something in their own life.

"What we have found in study after study is that people generally do not realize it is happening," Barsade explains. It can be "very insidious," and is part of why it's so important for people to know about emotional contagion, she adds.

Emotional contagion, used for good — On the flip side, emotional contagion can have tremendously positive effects.

"Emotional contagion is the basis of people interacting with each other and giving each other emotional support and empathy and all that through time immemorial," Barsade says.

When you're around positive people, it may help cheer you up. This happens on the individual, small group, organizational, and societal scale.

Interestingly, the people who are most emotionally contagious are often those in positions of power. That's because we absorb the emotions of those we pay most attention to: our bosses, our spouses, our close friends.

In a 2002 study, Barsade examined this phenomenon in a group of business school students. She and her team trained an actor to exhibit four emotional states: cheerful enthusiasm (pleasant and high energy), serene warmth (pleasant and low energy), hostile irritability (unpleasant and high energy), and depressed sluggishness (unpleasant and low energy).

Then, the team tracked each students' facial expressions and emotional responses as they completed various cooperative and competitive tasks. The students also self-reported their moods to the researchers.

After analyzing the data, Barsade found that every emotion expressed by the actor was contagious to the group. She also found that positive emotional contagion — the cheerful enthusiasm and serene warmth — led to less conflict, greater cooperation, and better performance by the students.

"We're all walking mood inductors," Barsade says, continuously influencing the moods, and, in turn, the judgments and behaviors of others.

The next time you feel antsy, upset, or on cloud nine, consider how you are expressing that feeling out to the world. It could be having far more influence than you ever realize.

To avoid falling into an “insidious” emotional-contagion trap, Barsade suggests following these steps:

1. Be aware: Take notice that you may feed off someone else’s strong emotion, and also be aware of your own mood.

2. Go verbal: When you can, pinpoint the source of the negative emotional contagion in yourself or others. "The best way, ultimately, to remove it is to try to address the issue directly," Barsade says.

3. Don't look: Emotional contagion hinges on paying attention, so if something is negatively affecting you, try to get it out of your area of attention. Turn off the TV, get off of social media for a while, or change the subject in conversation to something else.

4. Be thoughtful: If you are the source of the contagion, you want to be thoughtful about what you're doing that could transmit to others. Meanwhile, if you want to cheer yourself up, you also want to be thoughtful about what you're looking for. Surrounding yourself with other people who are in a better mood or watching something that can cheer you up can make a difference.