Effect of Biomechanical Force Exposure on Cognition & Brain Activation in Student

描述（由申请人提供）：美国每年有30万人遭受运动脑震荡，大多数高危运动员是高中水平的运动员。高中足球运动员是高危人群，约占高中运动员脑震荡总数的三分之二。运动性脑震荡的短期和长期影响，也许更重要的是反复的次震荡影响尚不清楚，反复损伤的累积影响也不清楚。结果有很大的可变性，尽管这种可变性的原因尚不清楚。我们建议利用现场头部撞击监测、认知测试和功能性脑成像方面的技术进步，首次了解哪种类型的头部撞击，在什么情况下，在哪些个体中，会对大脑功能产生什么影响。这一建议将有助于确定重复性生物力学力暴露对发育中的青少年大脑的短期和长期影响，为运动相关创伤性脑损伤的生物力学提供重要信息，并带来更明智的回归指导。

DESCRIPTION (provided by applicant): 300,000 individuals sustain sports concussions each year in the U.S. The majority of at-risk athletes are at the high school level. High school football players represent a particularly high-risk group, accounting for about two-thirds of all concussions in high school athletes. The short- and long-term effects of sports concussions and perhaps more importantly repetitive sub-concussive impacts are not known, nor are the cumulative effects of repeated injuries understood. There is enormous variability in outcome, although the reasons for this variability are not understood. We propose to use technological advances in on-field head impact monitoring, cognitive testing, and functional brain imaging to learn for the first time what types of head impacts, under what circumstances, in which individuals, cause what effects in brain function. This proposal will help to determine the short and long term effects of repetitive biomechanical force exposure on the developing adolescent brain, provide important information on the biomechanics of sports-related traumatic brain injury, and lead to more informed return-to-play guidelines. The overarching theme of this proposal is that a youth's exposure to biomechanical forces is a critical factor influencing cognitive outcome. This has two broad components: the characteristics of a single impact (e.g. linear acceleration, rotational acceleration, direction etc.), and the history of exposure to biomechanical forces over time (e.g. measures of frequency and intensity of impacts over the preceding days and weeks). We propose to use technological advances in on-field head impact monitoring, cognitive testing, and functional brain imaging to learn for the first time what types of head impacts, under what circumstances, in which individuals, cause what effects in brain function. Exposure to biomechanical forces acutely (post-concussive), sub-acutely (pre- to one-month post-season), and cumulatively (exposure over multiple seasons of play) are of interest and will be monitored. Two groups of high school student athletes (football players and non-impact sport athletes) will be studied at three time points (preseason, after a single season of play, and after multiple seasons of play) using a standardized cognitive battery and functional MRI (fMRI). A subgroup of students who sustain concussion, and matched controls from their team and from the non-impact athlete group will also be studied within one week of the concussion. Impact parameters will be directly measured using helmet-based accelerometer units.