Sensorimotor learning is thought to entail multiple learning processes, some volitional and others automatic. A new method to isolate implicit learning involves the use of a "clamped" visual perturbation in which, during a reaching movement, visual feedback is limited to a cursor that follows an invariant trajectory, offset from the target by a fixed angle. Despite full awareness that the cursor movement is not contingent on their behavior, as well as explicit instructions to ignore the cursor, systematic changes in motor behavior are observed, and these changes have the signatures of motor adaptation observed in studies using classic visuomotor perturbations. While it is clear that the response to clamped feedback occurs automatically, it remains unknown if participants are sensitive to the large deviations in hand position that occur during adaptation. To address this question, we used the clamp method and asked participants to report their hand position after each reach. As expected, we observed robust deviations in hand angle away from the target (average of ~18º). The hand reports also showed systematic deviations over the course of adaptation, initially attracted towards the visual feedback and then in the opposite direction, paralleling the shift in hand position. However, the shift in perceived hand position was subtle, reaching only ~2º at asymptote. These results confirm that participants have limited awareness of the behavioral changes that occur during sensorimotor adaptation, while revealing the impact of feedforward and feedback signals on their subjective experience.

中文翻译：

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感觉运动适应期间感测到的手部位置的连续报告。

感觉运动学习被认为需要多个学习过程，有些是自愿的，有些是自动的。一种隔离隐式学习的新方法涉及使用“钳位”视觉扰动，其中，在到达运动期间，视觉反馈仅限于遵循不变轨迹的光标，与目标偏移固定角度。尽管完全意识到光标移动并不取决于他们的行为，以及忽略光标的明确指令，但观察到运动行为的系统变化，并且这些变化具有在使用经典视觉运动扰动的研究中观察到的运动适应特征。很明显，对钳位反馈的响应是​​自动发生的，目前尚不清楚参与者是否对适应过程中出现的手部位置的大偏差敏感。为了解决这个问题，我们使用了夹钳方法，并要求参与者在每次到达后报告他们的手部位置。正如预期的那样，我们观察到远离目标的手角有很大的偏差（平均约 18º）。手部报告还显示了适应过程中的系统偏差，最初被视觉反馈吸引，然后在相反的方向上，与手部位置的变化平行。然而，感知手位置的变化是微妙的，在渐近线处仅达到约 2º。这些结果证实，参与者对感觉运动适应过程中发生的行为变化的认识有限，