Differentiating between two models of motor lateralization.
Differentiating between two models of motor lateralization.
复制标题
区分两种运动偏侧化模型。
DOI：
10.1152/jn.90349.2008
复制
发表时间：
2008
影响因子：
2.5
通讯作者：
Sainburg,RobertL
中科院分区：
文献类型：
--
作者：
Shabbott,BritneA;Sainburg,RobertL
本研究旨在区分运动侧化的两种模型：“反馈修正”和动态优势。反馈矫正假说认为，利手性反映了在视觉介导的矫正过程中占优势的半球优势，而动态优势则表明，每个半球都已成为专门用于控制的不同方面。该模型表明，主导半球专门用于控制任务动力学，这是协调有效轨迹所必需的，而非主导半球专门用于控制肢体阻抗，这是保持稳定姿态所必需的。为了区分这两种模型，我们检查了非优势臂和优势臂的视觉运动矫正是否有不同的介导。参与者在虚拟现实环境中进行目标到达，其中视觉运动旋转发生在两个方向，引起不同协调要求的纠正。反馈校正模型预测了在两个方向上校正的时间和精度的优势臂。动态优势预测两只手臂的矫正时机和准确度是相似的，但四肢间矫正质量的差异将取决于协调要求，从而取决于矫正的方向。我们的结果表明，校正时间和准确度不依赖于手臂。然而，通过轨迹曲率反映的修正质量同时取决于臂和旋转方向。在最高的协调要求下，非优势轨迹比优势轨迹更具有系统的曲线性。这些结果支持动态优势假说。
This study was designed to differentiate between two models of motor lateralization: “feedback corrections” and dynamic dominance. Whereas the feedback correction hypothesis suggests that handedness reflects a dominant hemisphere advantage for visual-mediated correction processes, dynamic dominance proposes that each hemisphere has become specialized for distinct aspects of control. This model suggests that the dominant hemisphere is specialized for controlling task dynamics, as required for coordinating efficient trajectories, and the nondominant hemisphere is specialized for controlling limb impedance, as required for maintaining stable postures. To differentiate between these two models, we examined whether visuomotor corrections are mediated differently for the nondominant and dominant arms. Participants performed targeted reaches in a virtual reality environment in which visuomotor rotations occurred in two directions that elicited corrections with different coordination requirements. The feedback correction model predicts a dominant arm advantage for the timing and accuracy of corrections in both directions. Dynamic dominance predicts that correction timing and accuracy will be similar for both arms, but that interlimb differences in the quality of corrections will depend on the coordination requirements, and thus, direction of corrections. Our results indicated that correction time and accuracy did not depend on arm. However, correction quality, as reflected by trajectory curvature, depended on both arm and rotation direction. Nondominant trajectories were systematically more curvilinear than dominant trajectories for corrections with the highest coordination requirement. These results support the dynamic dominance hypothesis.