UGA Biomechanics Laboratory and UGA Concussion Research Laboratory, Department of Kinesiology, University of Georgia, Athens, GA.
Med Sci Sports Exerc. 2020 Aug;52(8):1650-1657. doi: 10.1249/MSS.0000000000002300.
This study aimed to examine the association between clinical and functional reaction time (RT) assessments with and without simultaneous cognitive tasks among healthy individuals.
Participants (n = 41, 49% female; 22.5 ± 2.1 yr; 172.5 ± 11.9 cm; 71.0 ± 13.7 kg) completed clinical (drop stick, Stroop) and functional (gait, jump landing, single-leg hop, anticipated cut, unanticipated cut) RT assessments in random order. All RT assessments, except Stroop and unanticipated cut, were completed under single- (movement only) and dual-task conditions (movement and subtracting by 6s or 7s). Drop stick involved catching a randomly dropped rod embedded in a weighted disk. Stroop assessed RT via computerized neurocognitive testing. An instrumented walkway measured gait RT when center-of-pressure moved after random stimulus. All other functional RT assessments involved participants jumping forward and performing a vertical jump (jump landing), balancing on one leg (single-leg hop), or a 45° cut in a known (anticipated cut) or unknown (unanticipated cut) direction. RT was determined when the sacrum moved following random visual stimulus. Pearson correlation coefficients and a 5 × 2 repeated-measures ANOVA compared RT assessments and cognitive conditions.
Stroop RT outcomes did not significantly correlate with functional RT assessments (r range = -0.10 to 0.24). A significant assessment by cognitive task interaction (F4,160 = 14.01; P < 0.001) revealed faster single-task RT among all assessments compared with dual-task (mean differences, -0.11 to -0.09 s; P < 0.001), except drop stick (P = 0.195). Single-leg hop (0.58 ± 0.11 s) was significantly slower compared with jump landing (0.53 ± 0.10 s), anticipated cut (0.49 ± 0.09 s), gait (0.29 ± 0.07 s), and drop stick (0.21 ± 0.03 s; P values ≤ 0.001). Dual-task assessments were significantly slower than single-task assessments (mean difference, 0.08 s; P < 0.001).
Clinical and functional RT assessments were not correlated with each other, suggesting that sport-like RT is not being assessed after concussion. Functional and dual-task RT assessments may add clinical value and warrant further exploration after concussion.
本研究旨在探讨健康个体在进行伴有和不伴有同时认知任务的临床和功能反应时（RT）评估之间的关联。
参与者（n=41，女性占 49%；22.5±2.1 岁；172.5±11.9cm；71.0±13.7kg）以随机顺序完成临床（跌落棒、斯特鲁普）和功能（步态、跳跃着陆、单腿跳跃、预期切割、意外切割）RT 评估。除斯特鲁普和意外切割外，所有 RT 评估都是在单任务（仅运动）和双任务条件（运动和减去 6 秒或 7 秒）下完成的。跌落棒涉及到接住一个随机掉落的嵌入在带重物的圆盘的棒。斯特鲁普通过计算机化的神经认知测试来评估 RT。一个仪器化的步道在随机刺激后测量当重心移动时的步态 RT。所有其他功能 RT 评估都涉及参与者向前跳跃并进行垂直跳跃（跳跃着陆）、单腿平衡（单腿跳跃）或在已知（预期切割）或未知（意外切割）方向进行 45°切割。当骶骨随随机视觉刺激移动时，确定 RT。Pearson 相关系数和 5×2 重复测量方差分析比较了 RT 评估和认知任务。
斯特鲁普 RT 结果与功能 RT 评估无显著相关性（r 范围=-0.10 至 0.24）。一个显著的评估与认知任务的交互作用（F4,160=14.01；P<0.001）表明，与双任务相比，所有评估的单任务 RT 都更快（平均差异，-0.11 至-0.09s；P<0.001），除了跌落棒（P=0.195）。单腿跳跃（0.58±0.11s）明显比跳跃着陆（0.53±0.10s）、预期切割（0.49±0.09s）、步态（0.29±0.07s）和跌落棒（0.21±0.03s）慢（P 值均≤0.001）。双任务评估明显比单任务评估慢（平均差异，0.08s；P<0.001）。
临床和功能 RT 评估彼此之间没有相关性，这表明在脑震荡后不会评估运动型 RT。功能和双任务 RT 评估可能具有临床价值，值得在脑震荡后进一步探索。
