Study: Uncertainty Causes Stress Yet Improves Cognition

Conor Cawley

April Fools' Day is scary for a lot of reasons. You could get pranked, hoodwinked or even bamboozled before you even get out of bed.  But the biggest reason you're so worried about the first day of April is the uncertainty of it all. The lack of knowledge about when and where you will be pranked can add anxiety to the entire day. One study found that not knowing what's coming is more stressful than inevitable pain.

The study was conducted through a computer guessing game that asked participants to lift a series of rocks. Occasionally, there would be a snake waiting from them under the rock, in which case they were given a minor electric shock. Participants were split into two groups: a group that knew they were getting shocked, and one that didn't.

Measuring for stress, pupil dilation and perspiration, the study found some interesting results. For one, the presence of uncertainty created a significantly higher stress response in participants who knew they were going to be shocked.

“We saw exactly the same effects in our physiological measures – people sweat more and their pupils get bigger when they are more uncertain,” said lead author Archy de Berker to Katherine Derla of Tech Times.

However, this uncertainty-related stress might not be a bad thing. The study also found that participants who were more stressed were able to guess which rocks had snakes under them more effectively. These results imply that decision-making is positively affected by stress brought on by uncertainty in the long-run.

So, whether you are looking to improve your recent high score in Pac-Man or want to impress your boss with a stellar presentation, add a little uncertainty to the mix. You might get the added adrenaline you need to knock it out of the park.

Image via Flickr /Bernard Goldbach

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Conor is the Senior Writer for For the last five years, he’s written about everything from Kickstarter campaigns and budding startups to tech titans and innovative technologies. His extensive background in stand-up comedy made him the perfect person to host tech-centric events like Startup Night at SXSW and the Timmy Awards for Tech in Motion. You can email Conor at