Department of Kinesiology and Sport Management, Texas Tech University, 2500 Broadway Box 43011, Lubbock, TX, 79404, USA.
Department of Kinesiology and Physical Education, University of Lethbridge, 4401 University Drive, Lethbridge, AB, T1K 3M4, Canada.
Exp Brain Res. 2019 Dec;237(12):3297-3311. doi: 10.1007/s00221-019-05672-2. Epub 2019 Oct 29.
Previous research has established that the left cerebral hemisphere is dominant for the control of continuous bimanual movements. The lateralisation of motor control for discrete bimanual movements, in contrast, is underexplored. The purpose of the current study was to investigate which (if either) hemisphere is dominant for discrete bimanual movements. Twenty-one participants made bimanual reach-to-grasp movements towards pieces of candy. Participants grasped the candy to either place it in their mouths (grasp-to-eat) or in a receptacle near their mouths (grasp-to-place). Research has shown smaller maximum grip apertures (MGAs) for unimanual grasp-to-eat movements than unimanual grasp-to-place movements when controlled by the left hemisphere. In Experiment 1, participants made bimanual symmetric movements where both hands made grasp-to-eat or grasp-to-place movements. We hypothesised that a left hemisphere dominance for bimanual movements would cause smaller MGAs in both hands during bimanual grasp-to-eat movements compared to those in bimanual grasp-to-place movements. The results revealed that MGAs were indeed smaller for bimanual grasp-to-eat movements than grasp-to-place movements. This supports that the left hemisphere may be dominant for the control of bimanual symmetric movements, which agrees with studies on continuous bimanual movements. In Experiment 2, participants made bimanual asymmetric movements where one hand made a grasp-to-eat movement while the other hand made a grasp-to-place movement. The results failed to support the potential predictions of left hemisphere dominance, right hemisphere dominance, or contralateral control.
先前的研究已经证实，左大脑半球在控制连续的双手运动方面占主导地位。相比之下，离散双手运动的运动控制的偏侧化尚未得到充分探索。本研究的目的是调查哪一个（如果有的话）半球对离散双手运动占主导地位。21 名参与者进行了双手伸向糖果的伸手抓握动作。参与者抓糖果的目的要么是将其放入口中（抓握进食），要么是将其放入靠近嘴部的容器中（抓握放置）。研究表明，当由左半球控制时，单手抓握进食运动的最大握力开口（MGA）小于单手抓握放置运动。在实验 1 中，参与者进行了双手对称运动，双手均进行抓握进食或抓握放置运动。我们假设，双手运动的左半球优势会导致双手抓握进食运动时双手的 MGA 小于双手抓握放置运动。结果表明，双手抓握进食运动的 MGA 确实小于抓握放置运动。这支持左半球可能对双手对称运动的控制占主导地位，这与连续双手运动的研究一致。在实验 2 中，参与者进行了双手不对称运动，一只手进行抓握进食运动，另一只手进行抓握放置运动。结果未能支持左半球优势、右半球优势或对侧控制的潜在预测。
