The Sleep and Learning Lab at Michigan State University conducted one of the biggest sleep studies to date, finding that sleep deprivation impacts humans far more than previous ideas claimed.

The study, which was published in the Journal of Experimental Psychology: General, is one of the largest and first to look at how sleep deprivation affects peacekeeping, or the capacity to finish a set of tasks without losing one's place despite potential interruptions. This research relies on previous work by MSU sleep experts to measure the impact of a lack of sleep on a person's ability to follow a process and keep attention.

'Sleep deprivation increases the chances of making peacekeeping errors and triples the number of attention lapses, which is astonishing,' Fenn added. 'Sleep-deprived people must be extremely cautious in everything they do, and they cannot be trusted not to make costly mistakes. These mistakes can have disastrous implications in some cases, such as while driving an automobile.'

Fenn and co-authors Michelle Stepan, an MSU Ph.D. candidate, and Erik Altmann, a professor of psychology, believe that by revealing their results on the independent impacts of sleep deprivation on cognitive performance, individuals will recognize how severely their skills are hampered by a lack of sleep.

'Our findings disprove a popular belief that sleep deprivation simply affects attention,' said Stepan. 'Some sleep-deprived persons may be able to keep their composure while performing regular activities, like obtaining a patient's vitals. However, our findings show that doing a task that needs numerous stages, such as a doctor performing the medical treatment, is considered hazardous when sleep-deprived.'

The researchers enlisted the help of 138 volunteers for an overnight sleep study, with 77 staying awake all night and 61 going home to sleep. In the evening, all participants completed two distinct cognitive tasks: one that measured response time to a stimulus; and the other that measured reaction time to a stimulus. The other assessed a participant's ability to keep their place in a series of steps without skipping or repeating any of them, even when interrupted. In the morning, the participants performed both activities to assess how sleep loss affected their performance.

'After being interrupted, there was a 15% mistake rate in the evening, and we noticed that the error rate for the sleep-deprived group jumped to roughly 30% the next morning,' Stepan added. 'The morning scores of the rested individuals were identical to the night before.

'There are some jobs that people can accomplish on autopilot that aren't impaired by sleep deprivation,' Fenn said. 'However, sleep deprivation has a wide range of negative consequences in many aspects of life.'