School of Biological and Health Systems Engineering, Arizona State University, P.O. Box 879709, Tempe, AZ 85287, USA.
Neurosci Lett. 2011 Oct 10;503(3):186-90. doi: 10.1016/j.neulet.2011.08.032. Epub 2011 Aug 24.
The roles of visual and somatosensory information in arm movement planning remain enigmatic. Previous studies have examined these roles by dissociating visual and somatosensory cues about limb position prior to movement onset and examining the resulting effects on movements performed in the horizontal plane. Here we examined the effects of misaligned limb position cues prior to movement onset as reaches were planned and executed along different directions in the vertical plane. Movements were planned with somatosensory and visual feedback aligned at the starting position of the reach or with visual feedback displaced horizontally (Experiment 1) or vertically (Experiment 2). As in the horizontal plane, changes in movement directions induced by misaligned feedback indicated that vision and proprioception were both generally taken into account when planning vertical plane movements. However, we also found evidence that the contributions of vision and proprioception differed across target directions and between directions of displaced visual feedback. These findings suggest that the contributions of vision and proprioception to movement planning in the vertical plane reflect the unique multisensory and biomechanical demands associated with moving against gravity.
视觉和本体感觉信息在手臂运动规划中的作用仍然是个谜。以前的研究通过在运动开始前分离关于肢体位置的视觉和本体感觉线索，并检查对在水平面上执行的运动的影响，来研究这些作用。在这里，我们研究了在运动开始前肢体位置线索不对齐的情况下的影响，此时手臂沿着垂直面的不同方向进行计划和执行。在实验 1 中，手臂的运动计划是在触手可及的位置进行的，而在实验 2 中，手臂的运动计划是在触手可及的位置进行的，同时视觉反馈在水平方向上（实验 1）或垂直方向上（实验 2）发生了位移。与在水平面上一样，由反馈错位引起的运动方向的变化表明，在规划垂直平面运动时，视觉和本体感觉通常都被考虑在内。然而，我们也发现证据表明，视觉和本体感觉的贡献在目标方向和视觉反馈位移的方向之间存在差异。这些发现表明，视觉和本体感觉对垂直平面运动规划的贡献反映了与对抗重力移动相关的独特的多感觉和生物力学需求。
