Someone who is sleep-deprived is three times more likely to make potentially deadly lapses in concentration, a new study has found.
In one of the largest sleep studies of its kind, researchers from Michigan State University set out to quantify the effect that the lack of sleep has on a person's ability to follow a procedure and maintain attention.
The scientists recruited 138 people to participate in an overnight sleep assessment; 77 stayed awake all night, and 61 went home to sleep.
All participants took two separate cognitive tasks in the evening.
One measured reaction to stimulus, and another assessed a participant's ability to maintain their place in a series of steps without omitting or repeating a step - even after sporadic interruptions.
They then repeated both tasks in the morning, to see how sleep deprivation affected their performance.
Lead author Dr Kimberley Fenn said: "Our research showed that sleep deprivation doubles the odds of making place-keeping errors and triples the number of lapses in attention, which is startling.
"Sleep-deprived individuals need to exercise caution in absolutely everything that they do, and simply can't trust that they won't make costly errors.
"Oftentimes - like when behind the wheel of a car - these errors can have tragic consequences."
By sharing their findings, the researchers hope that people will acknowledge how significantly their abilities are hindered by a lack of sleep.
Co-author Michelle Stepan said: "Our findings debunk a common theory that suggests that attention is the only cognitive function affected by sleep deprivation.
Researcher Ms Stepan said. "Some sleep-deprived people might be able to hold it together under routine tasks, like a doctor taking a patient's vitals.
"But our results suggest that completing an activity that requires following multiple steps, such as a doctor completing a medical procedure, is much riskier under conditions of sleep deprivation.
"After being interrupted there was a 15 per cent error rate in the evening and we saw that the error rate spiked to about 30 per cent for the sleep-deprived group the following morning.
"The rested participants' morning scores were similar to the night before."
Dr Fenn added: "There are some tasks people can do on auto-pilot that may not be affected by a lack of sleep.
"However, sleep deprivation causes widespread deficits across all facets of life."
