TY - JOUR T1 - In the absence of diagnosed concussion in collegiate contact sport athletes, a relationship is suggested between the effects of head impact exposure, white matter diffusivity measures and cognition JF - Evidence Based Medicine JO - Evid Based Med SP - 157 LP - 157 DO - 10.1136/eb-2014-101750 VL - 19 IS - 4 AU - James L Stone AU - Julian E Bailes Y1 - 2014/08/01 UR - http://ebm.bmj.com/content/19/4/157.abstract N2 - Commentary on: McAllister TW, Ford JC, Flashman LA, et al. Effect of head impacts on diffusivity measures in a cohort of collegiate contact sport athletes. Neurology 2014;82:63–9.OpenUrlCrossRef There is growing concern that head impacts sustained during contact sports may lead not only to concussion but also to increased susceptibility to concussion, long-term cognitive decline and chronic traumatic encephalopathy. Study findings on this matter have been contradictory. A previous study by this group suggested that collegiate contact sport athletes are vulnerable to the cognitive effects of repetitive head impacts.1 Between 2007 and 2011, 80 non-concussed members of Division 1 National Collegiate Athletic Association American football and ice hockey teams were examined preseason and postseason with white matter MR diffusion imaging and cognitive testing at Dartmouth. Female ice hockey players were included. The contact sport athletes … ER -