Pearce Alan J, Hoy Kate, Rogers Mark A, Corp Daniel T, Maller Jerome J, Drury Hannah G K, Fitzgerald Paul B
1 Cognitive Neuroscience Laboratory, School of Psychology, Deakin University , Melbourne, Victoria, Australia .
J Neurotrauma. 2014 Jul 1;31(13):1139-45. doi: 10.1089/neu.2013.3219. Epub 2014 May 12.
This study investigated corticomotor excitability and inhibition, cognitive functioning, and fine motor dexterity in retired elite and amateur Australian football (AF) players who had sustained concussions during their playing careers. Forty male AF players who played at the elite level (n=20; mean age 49.7±5.7 years) or amateur level (n=20; mean age 48.4±6.9 years), and had sustained on average 3.2 concussions 21.9 years previously, were compared with 20 healthy age-matched male controls (mean age 47.56±6.85 years). All participants completed assessments of fine dexterity, visuomotor reaction time, spatial working memory (SWM), and associative learning (AL). Transcranial magnetic stimulation (TMS) was used to measure corticospinal excitability: stimulus-response (SR) curves and motor evoked potential (MEP) 125% of active motor threshold (aMT); and intracortical inhibition: cortical silent period (cSP), short-interval intracortical inhibition (SICI), and long-interval intracortical inhibition (LICI). Healthy participants performed better in dexterity (p=0.003), reaction (p=0.003), and movement time (p=0.037) than did both AF groups. Differences between AF groups were found in AL (p=0.027) and SWM (p=0.024). TMS measures revealed that both AF groups showed reduced cSP duration at 125% aMT (p>0.001) and differences in SR curves (p>0.001) than did healthy controls. Similarly, SICI (p=0.012) and LICI (p=0.009) were reduced in both AF groups compared with controls. Regression analyses revealed a significant contribution to differences in motor outcomes with the three measures of intracortical inhibition. The measures of inhibition differed, however, in terms of which performance measure they had a significant and unique predictive relationship with, reflecting the variety of participant concussion injuries. This study is the first to demonstrate differences in motor control and intracortical inhibition in AF players who had sustained concussions during their playing career two decades previously.
本研究调查了澳大利亚退役精英和业余足球(AF)运动员的皮质运动兴奋性和抑制、认知功能以及精细运动敏捷性,这些运动员在其职业生涯中曾遭受过脑震荡。将40名男性AF运动员(其中20名精英水平球员,平均年龄49.7±5.7岁;20名业余水平球员,平均年龄48.4±6.9岁)与20名年龄匹配的健康男性对照组(平均年龄47.56±6.85岁)进行比较,这些AF运动员平均在21.9年前遭受过3.2次脑震荡。所有参与者均完成了精细敏捷性、视觉运动反应时间、空间工作记忆(SWM)和联想学习(AL)的评估。经颅磁刺激(TMS)用于测量皮质脊髓兴奋性:刺激-反应(SR)曲线和运动诱发电位(MEP)为主动运动阈值(aMT)的125%;以及皮质内抑制:皮质静息期(cSP)、短间隔皮质内抑制(SICI)和长间隔皮质内抑制(LICI)。健康参与者在敏捷性(p=0.003)、反应(p=0.003)和运动时间(p=0.037)方面的表现均优于两个AF组。AF组之间在AL(p=0.027)和SWM(p=0.024)方面存在差异。TMS测量结果显示,两个AF组在aMT为125%时的cSP持续时间均缩短(p>0.001),且SR曲线与健康对照组存在差异(p>0.001)。同样,与对照组相比,两个AF组的SICI(p=0.012)和LICI(p=0.009)均降低。回归分析显示,皮质内抑制的三项测量指标对运动结果差异有显著贡献。然而,抑制指标在与哪些表现指标具有显著且独特的预测关系方面存在差异,这反映了参与者脑震荡损伤的多样性。本研究首次证明了在20年前职业生涯中曾遭受脑震荡的AF运动员的运动控制和皮质内抑制存在差异。