Sleep Deprivation May Lead to 'Optimism Bias,' Study Suggests

BananaStock/Thinkstock(DURHAM, N.C.) -- People who suffer from sleep deprivation may possess the tendency to make overly optimistic decisions, thus making them more likely to take larger financial risks -- particularly when gambling, according to a recent Duke University study.

Researchers in the study, published this week in the Journal of Neuroscience, asked 29 healthy adults to perform a series of gambling tasks after one normal night of sleep and again after staying up all night.

Next, the investigators took MRI scans of each volunteer and found that those who had been deprived of sleep had heightened activity in areas of the brain that assessed positive outcomes, while more rested individuals showed decreased activity in the areas that process negative outcomes.

"Using a risky decision-making task, we showed that sleep deprivation shifted most persons' bias from avoiding loss to pursuing gain," reported the Duke University researchers in North Carolina and Singapore.

The researchers concluded that lack of sleep "appears to create an optimism bias; for example, participants behave as if positive consequences are more likely (or more valuable) and as if negative consequences are less likely (or less harmful)."

That said, lead author Vinod Venkatraman, a Duke graduate student Psychology and Neuroscience, suggests that merely drinking caffeine or exercising are not enough to battle the effects of sleep deprivation.

"Late-night gamblers are fighting more than just the unfavorable odds of gambling machines; they are fighting a sleep-deprived brain's tendency to implicitly seek gains while discounting the impact of potential losses," he said.

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