Researchers from Harvard Medical School have been looking into the links between sleep deprivation and risk-taking. They measured people's risk taking by showing them a series of expanding balloons on a computer screen. The more the balloons expanded the more money they got but if the balloons popped they got nothing. The participants in the study were deprived of sleep for 75 hours. Half of the 25 volunteers (who were all aged between 20 and 35) were given caffeine gum and the other half were given a placebo. Both groups were unchanged in their risk-taking behaviour after 51 hours but after 75 hours without sleep the group who were given the placebo showed a significant increase in risk-taking. The study showed that there may be a 'breaking point' of sleep deprivation after which people are much more inclined to take risks and that caffeine can help to protect against this effect.
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