Further evidence of brain affect of sub-concussive blows

The body of research on the effect of sub-concussive blows to the brain is still developing. This recent study published this month in Neurology (abstract only) of  80 nonconcussed varsity football and ice hockey players and 79 non–contact sport athletes in a Division I NCAA athletic program concluded that head impact exposure negatively affected verbal learning and memory plus changed white matter by the end of the season. The subjects were evaluated before and after the season with brain scans plus learning and memory tests. All wore instrumented helmets that recorded the acceleration-time history of the head following impact. “A total of 20 percent of the contact-sport players and 11 percent of the non-contact athletes performed worse on a test of verbal learning and memory at the end of the season, a decline expected in less than 7 percent of a normal population, McAllister said. Those performing worse exhibited more changes in the corpus callosum region of the brain — a bundle of nerves connecting the left and right sides of the brain — than athletes who scored as predicted.”  Whether these changes reversed after the season was over was not in the scope of the study–an important factor in bolstering the validity of and preventing chronic traumatic encephalopathy (CTE) in sports.  HealthDay

Previously in TTA: Quantifying concussion and sub-concussion, Contact sports, long term effects and CTE, Acknowledging the reality of TBI in sports