Concussions may slow 'background' brain activity in athletes, new imaging shows
New research into post-concussion brain health suggests that the impact of head trauma may be more far-reaching than previously believed.
Using a specialized neuroimaging technique—resting-state magnetoencephalography, or MEG—experts found signs of slowed “background” activity in regions of the brain associated with concentration and memory. The study, which is set to be presented at the annual meeting of the Radiological Society of North America, is unique in that it focuses on aperiodic activity of the brain, providing potentially new insights into the extent of damage caused by head injuries.
"Most previous neuroscience research has focused on rhythmic brain signaling, which is also called periodic neurophysiology," lead author Kevin C. Yu, BS, a neuroscience student at Wake Forest University School of Medicine in Winston-Salem, North Carolina, said in a release on the findings. "On the other hand, aperiodic neurophysiology refers to brain signals that are not rhythmic."
"While it's often overlooked, aperiodic activity is important because it reflects brain cortical excitability," said study senior author Christopher T. Whitlow, MD, PhD, Meschan Distinguished Professor and Enterprise Chair of Radiology at Wake Forest University School of Medicine, added.
The authors note that aperiodic activity is commonly referred to as “background noise” on imaging. The team sought to determine if alterations of this sort of activity in football players who had sustained concussions would correlate with their post-injury healing progress. To do this, they acquired MEG imaging from 91 high school football players before and after their season. Findings from those exams were compared to the players’ Post-Concussive Symptom Inventory and pre- and post-season measures of behavioral and cognitive health.
During the season, 10 out of the 91 players sustained a concussion at some point. Those players showed slowed aperiodic activity on imaging, most notably in areas of the brain that contain chemicals related to memory and concentration. Lower test scores and more severe cognitive symptoms were also recorded in the concussion group.
These findings spur additional questions related to how concussions affect the brain’s chemical makeup, co-lead author Alex I. Wiesman, PhD, assistant professor at Simon Fraser University in Burnaby, British Columbia, suggested.
"Reduced excitability is conceptually a very different brain activity change than altered rhythms and means that a clear next step for this work is to see whether these changes are related to effects of concussion on the brain's chemistry,” Wiesman said.
The group suggested that their study could lead to changes in how concussion recovery is tracked in the future.
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