Doctors and scientists have created a pretty thorough theory of what happens to the brain during and immediately following the average concussive injury, but as with many theories it has proved more difficult to actually observe. It is obviously impossible to observe the brain during the actual moment of brain injury, but until recently no one had actually documented irregular brain activity within 24 hours of a concussive injury.
Now, findings published in the September issue of the Journal of the International Neuropsychological Society report observed irregular brain activity within 24 hours of a concussive injury, as well as an increased level of brain activity weeks later. That increased level of activity indicates the brain compensates for the injury as it recovers.
The study, reported by the Medical College of Wisconsin, evaluated 12 concussed high school football athletes and 12 uninjured teammates at 13 hours after an injury, and again seven weeks later. They were hoping to see the natural recovery of the brain from a sports-based concussion.
The concussed athletes exhibited traditional concussion symptoms such as decreased reaction time and lowered cognitive abilities, but most notably imaging via fMRI (functional magnetic resonance imaging) showed decreased activity in select regions of the brain’s right hemisphere. This would suggest the poor cognitive abilities of concussion patients is related to underactivation of attentional brain circuits.
Seven weeks after the intial scan and injury, the concussed athletes showed improvement of cognitive abilities and reaction time, but the imaging actually showed the post-concussed athletes had more activation in the brain’s attentional circuits than the non-concussed athletes.
“This hyperactivation may represent a compensatory brain response that mediates recovery,” said Dr. Thomas Hammeke, lead author of the study. “This is the first study to demonstrate that reversal in activation patterns, and that reversal matches the progression of symptoms from the time of the injury through clinical recovery.”