Tang Rixin, Ren Sixuan, Enns James T, Whitwell Robert L
The Department of Psychology, Nanjing University, Nanjing, Jiangsu, People's Republic of China.
Academic College, Zhejiang Shuren University, Linan, Zhejiang, People's Republic of China.
Acta Psychol (Amst). 2018 Jul;188:131-138. doi: 10.1016/j.actpsy.2018.04.017. Epub 2018 Jun 19.
Adaptive motor control is premised on the principle of movement minimization, which in turn is premised on a form of sensorimotor memory. But what is the nature of this memory and under what conditions does it operate? Here, we test the limits of sensorimotor memory in an intermanual context by testing the effect that the action performed by the left hand has on subsequent right hand grasps. Target feature-overlap predicts that sensorimotor memory is engaged when task-relevant sensory features of the target are similar across actions; partial effector-overlap predicts that sensorimotor memory is engaged when there is similarity in the task-relevant effectors used to perform an action; and the action-goal conjunction hypotheses predicts that sensorimotor memories are engaged when the action goal and the action type overlap. In three experiments, participants used their left hand to reach out and pick up an object, manually estimate its size, pinch it, look at it, or merely rest the left hand before reaching out to pick up a second object with their right hand. The in-flight anticipatory grip aperture of right-hand grasps was only influenced when it was preceded by grasps performed by the left-hand. Overlap in the sizes of the objects, partial overlap in the effectors used, and in the availability of haptic feedback bore no influence on this metric. These results support the hypothesis that intermanual transfer of sensorimotor memory on grasp execution is dependent on a conjunction of action type and goal.
适应性运动控制基于运动最小化原则，而运动最小化原则又基于一种形式的感觉运动记忆。但这种记忆的本质是什么，它在什么条件下发挥作用呢？在这里，我们通过测试左手执行的动作对后续右手抓握动作的影响，来检验感觉运动记忆在双手情境下的极限。目标特征重叠预测，当目标的与任务相关的感觉特征在不同动作之间相似时，感觉运动记忆会被激活；部分效应器重叠预测，当用于执行动作的与任务相关的效应器存在相似性时，感觉运动记忆会被激活；而动作目标联合假设预测，当动作目标和动作类型重叠时，感觉运动记忆会被激活。在三个实验中，参与者先用左手伸出并拿起一个物体，手动估计其大小，捏它，看它，或者只是在伸出右手拿起第二个物体之前让左手休息。只有在左手进行抓握动作之后，右手抓握动作的飞行中预期抓握孔径才会受到影响。物体大小的重叠、所用效应器的部分重叠以及触觉反馈的可用性对此指标均无影响。这些结果支持了这样一种假设，即感觉运动记忆在抓握执行上的双手间转移依赖于动作类型和目标的联合。
