With football season now underway, concerns are once again heating up about how to treat head injuries.
Concussions sideline athletes in many sports, and also affect people in situations like military battle and even car accidents. They can affect people's balance and steadiness, reaction time, ability to switch between tasks or make decisions, and their memories.
Recovery times tend to vary, in part because there is much that isn’t known about a concussed mind. But local researcher Dr. Tom Hammeke has some new answers.
They're based on his study that measures how the brain reacts to a concussion from the day after it occurs to seven weeks later.
"We were interested in trying to anchor this window of time after a concussion in which things are not functioning normally," he says. "The goal here was to try and determine what the window of vulnerability was for the brain.
Hammeke, a professor of psychiatry and behavioral medicine at the Zablocki VA Medical Center and the Medical College of Wisconsin, says he worked with high school teams to study injured players as well as their uninjured teammates as a control.
"We put them in an MR scanner and studied blood flow to different parts of their brain, both while they were resting as well as while they were doing tasks, and our goal was to look for any kinds of abnormalities that came about in those kinds of studies compared with their teammates that they were matched with," he says.
His tests found that injured players' reaction times were slower the morning after the concussion, their memories weaker, their balance was off and they didn't retain information as well. When scanning the brain, Hammeke also found that certain regions of the injured players' brains didn't get activated when they were performing certain tasks, as compared with their uninjured peers. These regions were linked with attention abilities.
Seven weeks later, however, Hammeke was surprised to see that the injured athletes had improved in memory, balance and other cognitive measures. Moreover, scans showed more activity in the attention area of their brains than in their peers.
But Hammeke warns this doesn't necessarily mean the brain is fully healed at that point. It's also possible the injured brain is overcompensating, which could explain the difference between the injured and uninjured athletes' scans.
"Even after a player is able to perform tasks relatively normally and is no longer complaining of symptoms, their brain might still be healing in some way and that's that window of vulnerability we're trying to anchor," he says.
More work is needed, Hammeke says, but it's important to pinpoint this timeline of healing because a person is less likely to fully heal if injured again while recovering from a previous concussion. He hopes his work will help establish future policies to treat concussions.
Dr. Hammeke's study on the Concussed Brain at Work appears in the September edition of the Journal of the International Neuropsychological Society.