Is Stress Contagious? A Study Reveals That Other People's Stress May Affect Your Brain Similarly To Your Own


A certain level of stress is essential for a person's survival. The chemicals released by your brain that cause pre-performance stage fright jitters are the same ones that alarmed your ancient ancestors of possible predators. But, seeing as most modern humans do not face the same risks as the bipeds who walked the earth millions of years ago, the body will sometimes react more intensely than it needs to. The impact of prolonged periods of intense stress is becoming increasingly apparent, and these effects, it seems, may not just put your wellbeing at risk.

New research out of Canada has found the other people's stress can change the chemical makeup of a person's brain, comparable to the way it does when someone experiences stress personally. Further, one's sex may play an integral role in the way stress is experienced — and how it is relieved.

In a groundbreaking study published in Nature Neuroscience, a team of scientists from the Hotchkiss Brain Institute (HBI) at the University of Calgary's Cumming School of Medicine explored the effects of stress on pairs of male and female mice. Researchers would remove one mouse from a pair before exposing the remaining mouse to a mild stressor. They then examined the parts of the brain associated with stress response (specifically, the CRH neurons) in both the mouse that was removed, and the remaining member of the pair.

The mouse exposed to a stressor naturally exhibited neurological evidence of stress following its exposure. But in an unprecedented twist, the mouse's counterpart showed an identical neurological reaction after the two were reunited; despite never being personally exposed to the stressor.

Further testing led researchers to conclude CRH, the main neuron being explored, releases a chemical signal or "alarm pheromone" when activated. When the chemical is released by the subject who experienced stress personally, it allows the partner who detects it to alert other members of a group of potential danger. This is an astounding development in terms of exploring the importance of social networks within a community, and provides even more insight into the evolutionary importance of stress.

Though arguably the most surprising finding of this series of experiments has to do with the effect the mice's sex had on how they perceive and experience stress. After being reunited with their partners, the levels of stress observed in female mice showed evidence of some reversal — suggesting an inherent catharsis linked to social interaction. Conversely, male mice under identical conditions did not exhibit any stress reversal when exposed to their original partners.

These discoveries provide previously evidence of an inherent link between social interaction and stress. Dr. Jaideep Bains, a professor in the Department of Physiology and Pharmacology at the University of Calgary explained to Science Daily, "We readily communicate our stress to others, sometimes without even knowing it." But, in humans, this is not always a positive thing. In fact in humans specifically, it would appear even unconscious transmittance of stress has the potential to do a great deal of harm.

"There is even evidence some symptoms of stress can persist in family and loved ones of individuals who suffer from PTSD. On the flip side, the ability to sense another's emotional state is a key part of creating and building social bonds," said Dr. Bains to Science Daily.

The implications of this study are important, and multilayered. Not only does it suggest merely being around other stressed people could increase one's own discomfort, it also adds to the concept that there may be, in fact, differences between the way individuals experience stress.

But if there is one central thing to take away from this extensive study, it is that you are likely not imagining your tendency to absorb your friends' stress. Plus, if it is you feeling it the most, talk to someone about it; science says for some people, it could help.