Research suggests that repeated impact to the head, like many contact athletes experience, can cause damage to the brain even without a concussion. Dr. Thomas McAlllister at Indiana University School of Medicine compared a group of college athletes engaged in contact sports like ice hockey and football with those participating in track and field.
The brains of all 159 athletes were scanned before and after the playing seasons. Other tests were also conducted to measure changes in learning. Accelerometers were attached to the helmets of those participating in contact sports to determine how frequently and intensely they experienced blows to the head.
Analyses of the magnetic resonance imaging showed that contact athletes had more damage to the white matter in their brains following the sports season. White matter is important in its influence on how a person learns.
Further, those athletes engaged in contact sports did not perform as well on certain tests measuring memory and learning at the end of the season. These types of changes were not found for students who engaged in noncontact sports activities like track and field.
As summarized by the lead researcher, “This…raises the question of whether repetitive impacts do result in some changes in white matter and those may be related to changes in cognition or learning.”