Motorists who get behind the wheel after a night of disturbed sleep could be posing as big a road safety risk as those that drive after no sleep at all, new research suggests.
The study saw a set of triplets asked to undertake various tasks while using a driving simulator at London's Transport Research Laboratory after experiencing three very different nights.
One of the 27-year-old brothers had enjoyed a full night of undisrupted sleep while another had not slept at all. The third sibling, meanwhile, had his sleep repeatedly interrupted by a crying robot baby.
During the 90-minute motorway simulation, the brothers were asked to stay in lane and maintain a constant speed of 60mph. They were also asked to flash their headlights every time they saw a red bar randomly appear over the road.
Researchers found the man whose sleep was disrupted had the slowest reaction times and was the worst at keeping his speed constant. He also failed to acknowledge the red bar twice as many times as the brother who had not slept at all.
The triplet driving after no sleep, however, left his designated lane more than 180 times during the hour-and-a-half drive. He was also said to have mentally disengaged from the task 76 times, something researchers say was as bad as nodding off behind the wheel.
The brother who had enjoyed an undisturbed night's sleep, meanwhile, was the best at staying in lane and was the only one of the three who managed to keep his speed constant.
The research was commissioned by online bed seller Time4Sleep. Company director Jonathan Warren says he hopes the findings will encourage motorists to think twice before driving after a lack of sleep.
Official figures suggest that driver fatigue is a contributory factor in up to one in five road accidents.
Copyright Press Association 2016. Motoring News articles do not reflect the RAC's views unless clearly stated.