Panzer Stefan, Kennedy Deanna, Leinen Peter, Pfeifer Christina, Shea Charles
Department of Sportscience, Saarland University, Im Stadtwald B8.2, 66041, Saarbrücken, Germany.
Department of Health and Kinesiology, Texas A&M University, College Station, TX, USA.
Exp Brain Res. 2021 May;239(5):1595-1605. doi: 10.1007/s00221-021-06082-z. Epub 2021 Mar 22.
In an experiment conducted by Kennedy et al. (Exp Brain Res 233:181-195, 2016), dominant right-handed individuals were required to produce a rhythm of isometric forces in a 2:1 or 1:2 bimanual coordination pattern. In the 2:1 pattern, the left limb performed the faster rhythm, while in the 1:2 pattern, the right limb produced the faster pattern. In the 1:2 pattern, interference occurred in the limb which had to produce the slower rhythm of forces. However, in the 2:1 condition, interference occurred in both limbs. The conclusion was that interference was not only influenced by movement frequency, but also influenced by limb dominance. The present experiment was designed to replicate these findings in dynamic bimanual 1:2 and 2:1 tasks where performers had to move one wrist faster than the other, and to determine the influence of limb dominance. Dominant left-handed (N = 10; LQ = - 89.81) and dominant right-handed (N = 14; LQ = 91.25) participants were required to perform a 2:1 and a 1:2 coordination pattern using Lissajous feedback. The harmonicity value was calculated to quantify the interference in the trial-time series. The analysis demonstrated that regardless of limb dominance, harmonicity was always lower in the slower moving limb than in the faster moving limb. The present results indicated that for dominant left- and dominant right-handers the faster moving limb influenced the slower moving limb. This is in accordance with the assumption that movement frequency has a higher impact on limb control in bimanual 2:1 and 1:2 coordination tasks than handedness.
在肯尼迪等人进行的一项实验中（《实验脑研究》233:181 - 195，2016年），要求惯用右手的个体以2:1或1:2的双手协调模式产生等长力的节奏。在2:1模式中，左肢执行较快的节奏，而在1:2模式中，右肢产生较快的节奏。在1:2模式中，干扰发生在必须产生较慢力节奏的肢体上。然而，在2:1条件下，两个肢体都出现了干扰。结论是干扰不仅受运动频率影响，还受肢体优势影响。本实验旨在重复这些发现在动态双手1:2和2:1任务中的情况，即参与者必须使一只手腕比另一只手腕移动得更快，并确定肢体优势的影响。要求惯用左手（N = 10；LQ = - 89.81）和惯用右手（N = 14；LQ = 91.25）的参与者使用李萨如图形反馈执行2:1和1:2的协调模式。计算谐波值以量化试验时间序列中的干扰。分析表明，无论肢体优势如何，较慢移动肢体的谐波性总是低于较快移动肢体。目前的结果表明，对于惯用左手和惯用右手的人来说，较快移动的肢体影响较慢移动的肢体。这与以下假设一致，即在双手2:1和1:2协调任务中，运动频率对肢体控制的影响比用手习惯更大。
