The effects of a concussion on a child's brain can last months after the initial injury, according to a small new study in the Journal of Neuroscience.
Researchers from the University of New Mexico and the Mind Research Network found that even if there are no symptoms months after a concussion, there are alterations in the white matter of the brain. And these changes -- which are seen two weeks after a concussion -- are still observed up to three months later.
"These findings may have important implications about when it is truly safe for a child to resume physical activities that may produce a second concussion, potentially further injuring an already vulnerable brain," study researcher Andrew Mayer, Ph.D., said in a statement.
The study included 15 children who had suffered a mild traumatic brain injury within the last 21 days, and 15 children who hadn't suffered any kind of brain injury. The researchers conducted diffusion tensor imaging on the children to analyze their brain white matter.
Four months after the initial injury, the researchers conducted the brain imaging tests again. They found that the kids who had suffered the brain injury had differences in white matter and cognitive skills compared with the kids who didn't have any brain injury -- even though those who had sustained injury no longer had lingering symptoms of their concussion.
The changes were so significant that researchers were able to tell 90 percent of the time which brains belonged to kids who had sustained the injury and which brains belonged to the injury-free kids.
This isn't the first time kids' concussions have been linked with lingering symptoms. In a study published earlier this year in the Archives of Pediatrics & Adolescent Medicine, researchers found that for about 20 percent of kids who've suffered a concussion, attention and memory problems can persist even a year after they've been injured, the Associated Press reported.
Another study, conducted by researchers from the Centers for Disease Control and Prevention, showed that kids' emergency room visits for concussions are increasing, with the number of going up 60 percent since 10 years ago.
But "it's a good increase, if that makes any sense," Steve Marshall, the interim director of the University of North Carolina's Injury Prevention and Research Center, who was not involved in that study, told the Associated Press. "These injuries were always there. It's not that there are more injuries now. It's just that now people are getting treatment that they weren't getting before."