Blows to the head not resulting in a concussion can still affect the brain hampering a person's memory and learning progress, according to a press release.
Most studies conducted on college sports head injuries have majorly focused on the effects of concussions incurred during such injuries. This is the first study to look into what happens to a person even if a blow on the head doesn't cause a concussion. Researchers found that such blows can affect the white matter in the brain, hampering cognition and thinking abilities.
"We found differences in the white matter of the brain in these college contact sport athletes compared to non-contact sport varsity athletes," said study author Thomas W. McAllister, MD, of Indiana University School of Medicine in Indianapolis. "The degree of white matter change in the contact sport athletes was greater in those who performed more poorly than expected on tests of memory and learning, suggesting a possible link in some athletes between how hard/often they are hit, white matter changes, and cognition, or memory and thinking abilities."
For the study, researchers from the university studied 80 concussion-free Division I NCAA Dartmouth College varsity football and ice hockey players. While playing the sport the participants were made to wear helmets that recorded the acceleration-time of the head following impact. The recordings were compared to similar recordings made on 79 non-contact sport players like skiing, crew and track. All participants underwent brain scans and took memory and learning tests before and at the end of the sports season.
At the end of the study, researchers found that 20 percent of contact players and 11 percent of non-contact players performed badly in memory and learning tests taken at the end of the season. They scored more than 1.5 standard deviations below the predicted score. Researchers noted that there was a marked difference in the corpus callosum region ( region having nerves that connect the right side of the brain to the left side) of the brain in these athletes than those who performed at par with the predicted scores.
"This group of athletes with different susceptibility to repetitive head impacts raises the question of what underlying factors might account for the changes in learning and memory, and whether those effects are long-term or short-lived," said McAllister.
An estimated 300,000 sport-related traumatic brain injuries, predominantly concussions, occur annually in the United States. Sports are second only to motor vehicle crashes as the leading cause of traumatic brain injury among people aged 15 to 24 years. According to an NCBI report, in all sports, collegiate athletes had higher rates of concussion than high school athletes, but concussions represented a greater proportion of all injuries among high school athletes.
