Eye-movement test to detect sleep loss

NASA has developed a test which uses a range of eye movements to detect acute sleep deprivation in people.

Lack of sleep is thought to play a role in up to 30% of all motor vehicle crashes and is even implicated in catastrophic events, such as the Chernobyl nuclear disaster, researchers said.

The study, published in The Journal of Physiology, shows that a range of eye-movement tests provide a reliable biomarker of individual acute sleep loss.

The research, conducted at NASA’s Ames Research Center in the US, found that a set of easily obtainable eye-movement measures could be used to provide a sensitive and reliable tool to detect small neural deficits.

Importantly, these measures could even be used to distinguish sleep-related impairment from that due to alcohol or brain injury.

The method

They had the participants spend up to 28 hours awake, and tested them periodically to monitor how their visual and eye-movement performance changed throughout the day-night cycle.

The researchers found that when participants were asked to track stimuli with unpredictable onset, direction, speed and starting location, human eye movements were dramatically impaired.

These findings have important implications for individuals who work in jobs requiring vigilant monitoring and precise motor action, such as military personnel, surgeons and truck drivers.

These measures could be used in assessing individuals working during the biological night, or following sleep loss.

“There are significant safety ramifications for workers who may be performing tasks that require precise visual coordination of one’s actions when sleep deprived or during night shifts,” said Lee Stone, senior author of the study.