Cognitive Decline and Aging: The Role of Concussive and Subconcussive Impacts

School of Kinesiology, University of Michigan at Ann Arbor, Ann Arbor, MI 48109, USA.
Exercise and sport sciences reviews (Impact Factor: 4.26). 07/2012; 40(3):138-44. DOI: 10.1097/JES.0b013e3182524273
Source: PubMed


BROGLIO, S.P., J.T, ECKNER, H.L. PAULSON, and J.S. KUTCHER. Cognitive decline and aging: the role of concussive and subconcussive impacts. Exerc. Sport Sci. Rev., Vol. 40, No. 3, pp. 138-144, 2012. Concussion has been viewed historically as a transient injury with no evidence supporting the existence of persistent effects. However, our recent work demonstrates electroencephalographic and motor control changes in otherwise healthy individuals with a history of concussion. We therefore hypothesize that concussive and subconcussive head impacts set about a cascade of pathological events that accelerates declines in cognitive function typically associated with the aging process.

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Available from: Henry Lauris Paulson, Jan 12, 2014
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    ABSTRACT: Purpose: Recent literature suggests that subconcussive impacts may influence cognitive functioning across the life span. These effects are suggested to manifest as functional and possibly structural changes. Head impact biomechanics during American football have been characterized from the high school to professional level, but style of play has not been considered. The aim of this investigation was to quantify and compare head impact frequencies and magnitudes between two different offensive schemes. Methods: We investigated the frequencies and magnitudes (linear acceleration [g], rotational acceleration [rad·s], and HITsp) of head impacts sustained by 83 high school football athletes, playing for schools using two different offensive schemes. The two schemes comprised a run-first offense (42 athletes) and a pass-first offense (41 athletes). The Head Impact Telemetry System was used to record head impact measures. Results: A total of 35,620 impacts were recorded across two seasons. Athletes in the run-first offense sustained an average of 456 head impacts per season (41 practices and 9 games), whereas the pass-first offense athletes sustained an average of 304 head impacts per season (44 practices and 9 games). The pass-first offense, however, sustained significantly higher impact magnitudes (P values < 0.05; 28.56g, 1777.58 rad·s, and 16.24) than the run-first offense (25.67g, 1675.36 rad·s, and 15.48) across a season. Conclusions: These data provide a first look at how different offensive strategies may influence head impact exposure in football athletes. In the study population, a run-first offense was associated with more frequent head impacts, of smaller magnitude, than a pass-first offense.
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