School of Human Kinetics, University of Ottawa, Ottawa, Canada.
PLoS One. 2021 Jan 11;16(1):e0245184. doi: 10.1371/journal.pone.0245184. eCollection 2021.
Reaching with a visuomotor distortion in a virtual environment leads to reach adaptation in the trained hand, and in the untrained hand. In the current study we asked if reach adaptation in the untrained (right) hand is due to transfer of explicit adaptation (EA; strategic changes in reaches) and/or implicit adaptation (IA; unconscious changes in reaches) from the trained (left) hand, and if this transfer changes depending on instructions provided. We further asked if EA and IA are retained in both the trained and untrained hands. Participants (n = 60) were divided into 3 groups (Instructed (provided with instructions on how to counteract the visuomotor distortion), Non-Instructed (no instructions provided), and Control (EA not assessed)). EA and IA were assessed in both the trained and untrained hands immediately following rotated reach training with a 40° visuomotor distortion, and again 24 hours later by having participants reach in the absence of cursor feedback. Participants were to reach (1) so that the cursor landed on the target (EA + IA), and (2) so that their hand landed on the target (IA). Results revealed that, while initial EA observed in the trained hand was greater for the Instructed versus Non-Instructed group, the full extent of EA transferred between hands for both groups and was retained across days. IA observed in the trained hand was greatest in the Non-Instructed group. However, IA did not significantly transfer between hands for any of the three groups. Limited retention of IA was observed in the trained hand. Together, these results suggest that while initial EA and IA in the trained hand are dependent on instructions provided, transfer and retention of visuomotor adaptation to a large visuomotor distortion are driven almost exclusively by EA.
在虚拟环境中使用视动觉扭曲进行伸手动作会导致训练手和非训练手发生伸手适应。在目前的研究中，我们想知道非训练手（右手）的伸手适应是否是由于从训练手（左手）转移而来的显性适应（EA；伸手时的策略性改变）和/或隐性适应（IA；伸手时的无意识改变）引起的，如果这种转移会因所提供的指令而改变。我们还想知道 EA 和 IA 是否在训练手和非训练手中都得到保留。参与者（n = 60）被分为 3 组（指令组（提供了如何对抗视动觉扭曲的说明）、非指令组（未提供说明）和对照组（未评估 EA））。在经过 40°视动觉扭曲的旋转伸手训练后，立即在训练手和非训练手中评估 EA 和 IA，24 小时后，让参与者在没有光标反馈的情况下伸手。参与者的伸手任务包括（1）使光标落在目标上（EA+IA），和（2）使手落在目标上（IA）。结果表明，虽然训练手的初始 EA 在指令组中大于非指令组，但两组之间的 EA 完全转移，且在两天后仍然保留。在非指令组中，训练手的 IA 最大。然而，对于任何一组，IA 都没有显著地从一只手转移到另一只手。在训练手中，IA 的保留有限。总的来说，这些结果表明，虽然训练手的初始 EA 和 IA 依赖于所提供的指令，但对大视动觉扭曲的视动觉适应的转移和保留几乎完全由 EA 驱动。
