There is also a difference in the velocity of different parts of the body. When a normal, healthy person walks, the foot "kicks" forward at about six meters per second, she said. "When they are wearing the visual impairment goggles the kicks decrease in velocity and they become less regular."
Those differences might be too subtle to be detected by a coach, or even a trained medical specialist, but they can't fool the radar, the researchers said. At least, not all the time.
It would be helpful to have both before and after data on every athlete, or soldier, but that isn't practical. But the researchers say they can compile data bases showing the characteristics of average healthy individuals and concussed persons, and the system should be able to determine which category a person belongs in.
As with any medical diagnostic tool, there will always be some false positives, and the system can be fine tuned to different thresholds of sensitivity. A high school football coach, for example, may want to err on the side of caution, even if it means more athletes will be sidelined to reduce the possibility of a second concussion. A battlefield commander whose troops are facing life or death, by contrast, may be less inclined to pull someone from the field because he or she may have a concussion, and thus would want a very high threshold of proof.
Researchers: Athlete with Concussion Could Show Decline More Than 30 Years Later
Most concussions can be described as mild brain injuries, but the effect can be long lasting.
Researchers in Canada found that an athlete who suffers a concussion will probably show a decline in mental and physical processes more than 30 years later.
The gridiron is particularly dangerous. Scientists at the University of North Carolina at Chapel Hill found that football players who suffer a concussion are three times more likely than other players to suffer a second concussion in the same season.
In many cases, the athlete is a poor judge of his or her own condition, according to studies at the University of Pittsburgh Medical Center. For whatever reason, the victim will often understate the symptoms, returning to the field far too soon.
Radar, of course, is not going to solve all those problems. But any tool that increases the chances of early detection of a concussion could prove valuable. That diagnosis should be followed up with a clinical evaluation, and the sooner that happens, the better.