New scientific research conducted at Australia’s RMIT University has revealed a hidden way that automobiles may be killing their own drivers — and others — according to a study published in the journal Ergonomics last week. The study found that low-level vibrations that occur unavoidably in most cars have a significant effect of driver fatigue.
According to the Center for Disease Control in Atlanta, as many as 6,000 fatal automobile accidents in the United States each year are directly caused by driver fatigue. With auto fatalities rising above 40,000 in 2016, according to The New York Times, that means approximately 15 percent of all people who die each year in traffic accidents in the U.S. are killed by drowsy drivers — including the drivers themselves.
“No one knows the exact moment when sleep comes over their body. Falling asleep at the wheel is clearly dangerous, but being sleepy affects your ability to drive safely even if you don’t fall asleep,” according to the CDC.
In Australia, that number is about 20 percent — one of every five — according to the Australian state of Victoria’s Transport Accident Commission.
So what can be done to cut down on the tragedies cause by sleepy drivers? The new RMIT study suggests that manufacturing cars that minimize vibrations as the car moves would be a big help.
The vibrations made by cars and trucks as they run often cannot even be perceived by their drivers, due to their low frequencies. But subjects in the RMIT University experiment — who were placed in a simulator controlled by the scientists, not in actual moving cars — showed significant signs of drowsiness “requiring substantial effort to maintain alertness and cognitive performance” within as little as 15 minutes of getting behind the wheel, according to a summary of the study published by Science Daily.
“When you’re tired, it doesn’t take much to start nodding off and we’ve found that the gentle vibrations made by car seats as you drive can lull your brain and body,” said RMIT Psychology Professor Stephen Robinson, who authored the study, as quoted by Newsweek. “Our study shows steady vibrations at low frequencies — the kind we experience when driving cars and trucks — progressively induce sleepiness even among people who are well rested and healthy.”
The researchers measured their subjects’ drowsiness using the Karolinska Sleepiness Scale, a questionnaire that asks participants to rate their level of alertness on a scale of one to nine, according to the site InterDynamics, with “one” being “extremely alert,” and “nine” indicating that the subject feels “extremely sleepy, fighting sleep.”
A study published in 2006 by the journal Clinical Neurophysiology confirmed that the Karolinska scale displays “a high validity in measuring sleepiness.”
But the Australian study also contained some good news — moving cars may also produce “good vibrations” which can have the opposite effect on drivers, actually increasing alertness. But the study’s authors say that more research is needed to determine the range of frequencies that could help keep drivers awake and possibly cut down on fatalities caused by drowsy driving, according to the industry site Australasin Transport News.