Researchers have found that uncertainty causes more stress than inevitable pain. Findings show that people are more damned not knowing an outcome than knowing for sure that something painful will come.

A research team from the University College London conducted an experiment wherein 45 volunteers played a computer game to test their stress levels. In the game, they needed to turn over rocks that may or may not have snakes under them.

It's a guessing game. If they turned over a rock with a snake underneath, they will receive a mild electric shock on their hands. The participants were divided into two groups. One group knew they would get a mild electric shock while the others had to guess which rocks were safe.

In time, the participants became better at guessing which rocks had snakes underneath, but the researchers made sure the uncertainty level was high through the video game — so they kept swapping the rocks with snakes underneath.

Apart from monitoring the participants' perspiration and pupil dilation, the team measured the participants' uncertainty and the resulting stress levels throughout the game. Both levels matched with the participants' reported stress levels after finishing the video game.

They found that the anxiety levels of those who didn't know if they will receive a mild electric shot or not were higher than those who knew and anticipated the shock. Interestingly, they discovered that the participants with higher stress levels helped them in assessing the risk better.

This means that the people who were the most stressed during their times of uncertainty performed better in judging whether the rocks had snakes or not. The findings suggested that uncertainty-related stress helps people in making decisions in the long run.

"It turns out that it's much worse not knowing you are going to get a shock than knowing you definitely will or won't. 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.

The Medical Research Council (MRC) funded the study, which was published in the journal Nature Communications on March 29.

Photo: Peter Wilson | Flickr