Ben Roethlisberger of the Pittsburgh Steelers is tested for a concussion. A new device aims to speed concussion detection by examining blinking. (Photo by Justin K. Aller/Getty Images)
There’s considerable discussion regarding how football players’ brains are affected by minor, repetitive collisions that occur throughout a game, not just from the hits that result in concussions. But a new study out of Indiana University suggests that football players’ brain activity may appear altered because of brain reorganization that occurs when mastering hand-eye coordinations unique to contact sports, and not necessarily because of subconcussive hits.
The study took 21 football players and 19 cross-country runners and scanned their brains using fMRI. The football players did not already have a history of concussions. Eleven students who were not athletes were also studied. All of the study participants underwent a simple visual assessment known as smooth pursuit, which is designed to use eye movements to probe brain functioning and has been demonstrated to show reduced performance in concussed patients.
No differences were found in how each group performed the task, but the fMRI results revealed differences in the brains of the football players compared to the cross-country runners and non-athletes, with the most visible differences in activity occurring in the part of the brain responsible for visual processing.
“We focused on these brain regions because physicians and trainers regularly encounter large deficits in players’ ability to smoothly track a moving point with their eyes after suffering an acute concussion,” said Nicholas Port, an author on the study and a professor of optometry at Indiana University Bloomington.
“Everyone from musicians to taxi drivers has differences in brain activity related to their specific skills. The differences in this study may reflect a lifetime exposure of subconcussive blows to the head, or they could simply be the result of playing a visually demanding sport where you’re constantly using your hands and tracking the ball.”
The report’s conclusion noted two prevailing possibilities:
Greater cerebellar activity among football players while performing an oculomotor task could indicate that they are working harder to compensate for some subtle, long-term subconcussive deficits. Alternatively, top athletes in a sport requiring high visual motor skill could have more of their cerebellum and FEF devoted to oculomotor task performance regardless of subconcussive history. Overall, these results provide little firm support for an effect of accumulated subconcussion exposure on brain function.
Each of these findings, albeit incomplete, presents a unique approach to understanding the role of subconcussive hits in contact sports. The former could mean that as contact athletes sustain those hits, their brain adapts in a manner that changes their visual processing ability. The latter could mean that even without repeated hits to the head, contact athletes practice hand-eye coordination so frequently that their visual processing centers show different activity compared to those of non-contact athletes.
You can read the full report of the study here.
SportTechie Takeaway:
It’s too bad the researchers compared football players to cross-country athletes, and not to athletes in another sport with less potential for head trauma but more demand for the type of hand-eye coordination they noted. Soccer, basketball and baseball come to mind. The report notes that a “possible method for surmounting this difficulty would be to repeat this study with a within-sport design, using accelerometer data to differentiate those who experienced greater and lesser hits to the brain during the season.” A study including flag football athletes might provide the ideal “within-sport design” the researchers suggest.
Suggested further reading (listening):
Examining Brain Functioning In Athletes With SyncThink’s Scott Anderson
