In this study, we aimed to examine features of interlimb generalization or "transfer" of newly acquired motor skills with a broader goal of better understanding the mechanisms mediating skill learning. Right-handed participants (n=36) learned a motor task that required them to make very rapid but accurate reaches to 1 of 8 randomly presented targets, thus bettering the typical speed-accuracy tradeoff. Subjects were divided into an "RL" group that first trained with the right arm and was then tested on the left, and an "LR" group that trained with the left arm and was subsequently tested on the right. We found significant interlimb transfer in both groups. Remarkably, we also observed that participants learned faster with their left arm compared to the right. We hypothesized that this could be due to a previously suggested left arm-right hemisphere advantage for movements under variable task conditions. To corroborate this, we recruited two additional groups of participants (n=22) that practiced the same task under a single target condition. This removal of task level variability eliminated learning rate differences between the arms, yet, interlimb transfer remained robust and symmetric, as in the first experiment. Additionally, the approach adopted to reduce errors during learning, though heterogeneous across subjects particularly in our second experiment, was transferred to the untrained arm. These findings may be best explained as the outcome of the operation of cognitive strategies during the early stages of motor skill learning.

中文翻译：

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新获得的熟练动作的对称跨肢转移。

在这项研究中，我们旨在研究新获得的运动技能的跨肢概括或“转移”的特征，其更广泛的目标是更好地理解调节技能学习的机制。惯用右手的参与者 (n=36) 学习了一项运动任务，该任务要求他们非常快速但准确地到达 8 个随机呈现的目标中的 1 个，从而改善了典型的速度 - 准确性权衡。受试者被分为“RL”组，首先用右臂训练，然后在左侧测试，“LR”组，用左臂训练，随后在右侧测试。我们在两组中都发现了显着的肢体间转移。值得注意的是，我们还观察到，与右臂相比，参与者的左臂学习速度更快。我们假设这可能是由于先前建议的左臂-右半球在可变任务条件下的运动优势。为了证实这一点，我们招募了另外两组参与者 (n=22)，他们在单一目标条件下练习相同的任务。消除任务级别的可变性消除了手臂之间的学习率差异，但与第一个实验一样，肢体间转移仍然保持稳健和对称。此外，在学习过程中采用的减少错误的方法，尽管在不同学科中尤其是在我们的第二个实验中是异质的，但被转移到了未经训练的手臂上。这些发现可以最好地解释为在运动技能学习的早期阶段认知策略的运作结果。