Trial participants were kept awake for 36 hours before driving for two hours on a closed track. Source: Swinburne University of Technology An eye-tracking system developed by researchers from Swinburne and Austin Health that detects drowsy drivers could potentially reduce the number of automobile accidents caused by sleep-deprived drivers.

Causing roughly 20 percent to 30 percent of car accidents in Australia, researchers determined that a person's visual attention (being able to scan environments to avoid possible hazards) diminishes when they are sleep deprived.

"Although gains have been made in areas of road safety such as drink driving and speeding, it hasn't been until recently that developing technologies can allow us to identify the altered ocular activity associated with drowsiness as a cause of accidents," said Associate Professor Luke Downey, lead Swinburne researcher from the Centre for Human Psychopharmacology.

According to Associate Professor Mark Howard of Austin Health's Institute of Breathing and Sleep, and principal investigator of the study, "Not only can we use these measures to monitor and evaluate drowsiness but they can then be used for potentially alerting the driver to impairment in real time or to a centralized base (e.g., truck company monitoring base).

"The measures could also be used to evaluate the impact of legislative changes on driver drowsiness and used by transport companies to assess whether particular schedules are dangerous," he said.

In a demonstration of the dangers of driving while sleep deprived, researchers kept study participants awake for 36 hours before having participants get behind the wheel and drive a car for two hours on a closed driving track. While participants drove, visual attention was measured by the eye-tracking system.

Researchers concluded that sleep deprivation affected eye movement control, increasing the likelihood that sleep-deprived drivers would veer out of their lanes — at least three times more often than non-sleep-deprived drivers.

Other findings, according to researchers, include the sleep-deprived drivers' reduced ability to visually fix on other objects and that sleep-deprived drivers' eyes closed for longer durations when blinking.

"Normally during driving we would be looking at hazards on the side of the road and hazards ahead in traffic, but sleep deprivation impairs our ability to do this," Howard said. "Part of the reason for this is that your gaze becomes more random than planned and part of it is to do with eye closure."

The study is detailed in the journal Scientific Reports.