The Effects of Concussive and Sub-concussive Head Impacts on Brain Activity.

Concussion;Kinesiology and Sports;Health Sciences;Kinesiology

Williams, Richelle M.McLeod, Tamara C Valovich ;

University of Michigan

关键词: Concussion;    Kinesiology and Sports;    Health Sciences;    Kinesiology;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/133275/richellm_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Context: 7 million athletes participate in high school sports annually. Approximately 1 million of these athletes participate in football, which is associated with repetitive head impacts. Concussion literature suggests sub-concussive impacts may lead to declines in brain function across a season of football. Furthermore, recent research suggests following clinical concussion recovery, metabolic and neurophysiological recovery may not be complete.Objective: The purpose of this study was to monitor head impacts and cognitive function during (72hour, asymptomatic) and after concussion and longer term over a full football season (pre-season, mid-season, post-season).Participants: 106 male adolescent (46 football-athletes, 42 controls for football-athletes, 9 concussed-athletes, 9 controls for concussed-athletes).Outcome measures: The Head Impact Telemetry System encoder was used to track the location and magnitude of head impacts during football participation. Psychophysiology was measured using Electroencephalography and was quantified using a 256 channel system to record brain activity during an auditory oddball task.All Participants completed Axon neurocognitive testing, clinical reaction time task (CRT), symptom inventory and two Health Related Quality of Life Surveys (Health Behavior Inventory, Satisfaction with Life) throughout the above testing time-points. Results: Football-athletes sustained a mean of 482 head impacts during all practices and games. Mixed measures ANOVA indicated a significant decrement on one BNA output score, Target amplitude, with lower post-season scores (p<0.05). No other BNA output scores, Axon, CRT, SWL, or HBI measurements showed significant deficits post-season (p>0.05). Furthermore, P3a amplitudes were significantly larger and N2 latency was longer during post-season testing. Mixed measured ANOVAs indicated no significant deficits in BNA output scores, Axon performance, CRT, and HRQOL, for concussed and matched controls across post-injury time points. Additionally, there was a significantly longer P3a latency post-season latencies across groups and smaller P3a amplitudes at post-season for concussed compared to controls (p<0.05).Conclusion: Overall, these findings suggest electrophysiology changes between pre and post-season testing among football athletes and control participants without concussion, with the majority demonstrating improved cognitive function. Therefore, no negative effects may be associated with repeated head impacts in one season of football. Furthermore, no cognitive deficits were present during asymptomatic testing following concussion.