When faced with a possibly unpleasant situation, many of us would rather receive bad news right away than grapple with the stress of uncertainty. Now research by scientists from University College London lends credence to the idea that an unknown outcome is more stressful than actually receiving an undesirable one.
In the study, which was published in Nature Communications, the researchers tasked 45 volunteers to play a computer game that consisted of turning over rocks that could conceal snakes. The goal of the game was to guess which rocks concealed snakes and turn over the stones that were snake-free. But the game had two twists: Players received an electric shock every time they turned over a stone that hid a snake, and the likelihood of encountering a snake became less predictable over time.
The researchers assessed the players' responses to uncertainty and the (quite literal) shock of finding a snake by measuring each player's pupil dilation, sweat levels and self-reports of stress. They verified these measures of stress by comparing them to cortisol levels in each player's saliva.
They found that volunteers were most stressed when they had a 50/50 chance of receiving a shock and were least stressed when the outcome was known; even it if meant they had a 100 percent chance of getting a painful shock.
The study's sample size was modest, but even so, these findings could have interesting implications for patient care. As the researchers point out, it's not much of a stretch to imagine a scenario where a patient feels anxiety over an uncertain appointment, test result or treatment. Knowing that uncertain situations could (as the study suggests) be especially stressful gives physicians and patients a chance to employ stress-reducing techniques when needed most.