TUESDAY, Aug. 11, 2020 (HealthDay News) -- After a concussion, it may not be safe to drive for a while, a new, small study suggests.
"People who have concussions often have slower reaction times as a result, and do more poorly on tests of thinking skills after their injury than their peers without concussions," said researcher Julianne Schmidt, from the University of Georgia.
"Our study suggests that complicated driving skills, the kind involving split-second reaction times that could mean the difference between life and death, are the ones that may take the longest to regain after you have a concussion -- even when all of your symptoms have resolved," she added.
The study involved 28 college students, average age 20, including 14 with concussions and 14 without. They completed a simulated driving reaction time test and a computerized mental acuity test 48 hours after their concussion symptoms disappeared -- about 16 days after the injury.
The drivers with concussions had slower reaction times than those without a head injury by an average of nearly one second.
At a stoplight, it took those with concussions 0.24 seconds longer to react, an equivalent of nearly 16 feet in stopping distance, compared with those without concussions.
During the driving simulation, which included the image of a child running in front of a car, the concussion group took 0.06 seconds longer to react, the equivalent of 3 feet in stopping distance.
The study results were presented last week at a virtual meeting of the American Academy of Neurology.
Slowed reaction time is a predictor of crash risk, and split-second delays can be critical for avoiding a crash.
"Overall, after the symptoms of the drivers with concussions resolved, their reaction times were similar to drivers who didn't have concussions. However, when we looked specifically at stoplight reaction time, we saw lingering deficits in the drivers who had concussions," Schmidt said in an academy news release.
"This could mean traditional reaction time tests aren't the best measure of driving responsiveness and readiness. And that could have important public safety implications," Schmidt said, noting that there are more than 3 million sports-related concussions in the United States each year.
Data and conclusions presented at meetings are usually considered preliminary until peer-reviewed for publication in a medical journal.
For more on concussion, head to the U.S. Centers for Disease Control and Prevention.
SOURCE: American Academy of Neurology, news release, July 29, 2020