
@article{ref1,
title="Clinical versus functional reaction time: implications for postconcussion management",
journal="Medicine and science in sports and exercise",
year="2020",
author="Lempke, Landon B. and Johnson, Rachel S. and Schmidt, Julianne D. and Lynall, Robert C.",
volume="ePub",
number="ePub",
pages="ePub-ePub",
abstract="PURPOSE: Examine the association between clinical and functional reaction time (RT) assessments with and without simultaneous cognitive tasks among healthy individuals. <br><br>METHODS: Participants (n=41, 49% female; 22.5±2.1yrs; 172.5±11.9cm; 71.0±13.7kg) 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 6's or 7's). 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 5x2 repeated-measures ANOVA compared RT assessments and cognitive conditions. <br><br>RESULTS: Stroop RT outcomes did not significantly correlate with functional RT assessments (r-range=-0.10,0.24). A significant assessment by cognitive task interaction (F4,160=14.01;p<0.001) revealed faster single-task RT among all assessments compared to dual-task (mean differences:-0.11,-0.09s;p<0.001), except drop stick(p=0.195). Single leg hop (0.58±0.11s) was significantly slower compared to jump landing (0.53±0.10s), anticipated cut (0.49±0.09s), gait (0.29±0.07s), and drop stick (0.21±0.03s;p's≤0.001). Dual-task assessments were significantly slower than single-task (mean difference: 0.08s;p<0.001). <br><br>CONCLUSION: Clinical and functional RT assessments were not correlated with each other, suggesting sport-like RT is not being assessed post-concussion. Functional and dual-task RT assessments may add clinical value and warrant further exploration post-concussion.<p /> <p>Language: en</p>",
language="en",
issn="0195-9131",
doi="10.1249/MSS.0000000000002300",
url="http://dx.doi.org/10.1249/MSS.0000000000002300"
}