A study by researchers at Germany's Max Planck Institute for Cognitive and Brain Sciences in Leipzig and the Technische Universität Dresden didn't specifically set out to test if watching tense shows such as 24 or Homeland turns us into quivering masses of stress Jello, but that seems to be the takeaway. More worrisome, perhaps, is that you can "catch" stress just by watching people confront anxiety-provoking situations onscreen.

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Researchers recruited 362 people for the experiment: Everyone was tested in pairs—one sacrificial lamb exposed to a "psychosocial stressor" and one observer. Some of the pairs consisted of intimate couples and some were made up of strangers. While there are an infinite number of sadistic ways to stress people out (toss them into the tiger pit at the Leipzig Zoo? Virtual reality battle with The Mountain from Game of Thrones?), the chosen psychosocial triggers in this case were "difficult mental arithmetic tasks" and a faux job interview. In case people found math and a job interviews relaxing, two people posing as behavior analysts also sat in the room with the subjects (performance anxiety, anyone?).

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While one partner did either the math and the interview, the counterpart simply watched the session, either through a one-way mirror or via a video monitor.

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Here's what researchers found:

  • 95% of the people who did the math and job interview session experienced a rise in levels of the stress hormone cortisol, a physiological indicator that they were, indeed, stressed out.
  • Watching through the one-way mirror led to elevated cortisol in 30% of observers.
  • Viewing on the video monitor had a slightly less potent effect, with 26% getting vicariously stressed.
  • 40% of observers were stressed out by watching their romantic partner endure stress.
  • Watching a stranger struggle elicited a cortisol jolt in 10% of observers.
  • Finally, researchers found that men and women observers were stressed in equal numbers, so you can't keep telling people that women are hard-wired to be more empathetic than men.

In many ways these results aren't really surprising. We've all yelled at a friend or loved one who was nervously pacing around, "Sit your ass down, you're stressing me out!" We know, intuitively, that being around stressed out people can be stressful, too. But to see it confirmed—"empathic stress" (i.e., "a full-blown physiological stress response that arises solely by observing a target undergo a stressful situation")—is alarming. The researchers were surprised too. "The fact that we could actually measure this empathic stress in the form of a significant hormone release was astonishing," said Veronika Engert, one of the study's lead authors.

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Especially surprising was the fact that watching a stressful situation mediated by way of a screen can "contaminate" us with stress. Again, the researchers didn't test subjects as they watched TV shows, but that didn't stop Engert from speculating about how her team's research might apply to that scenario. "This means that even television programs depicting the suffering of other people can transmit that stress to viewers," she said. Let's all start by watching less news...

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