Wong Teser, Henriques Denise Y P
York University, School of Kinesiology and Health Science, Center for Vision Research, 4700 Keele Street, Toronto, ON, Canada M3J 1P3.
J Neurophysiol. 2009 Feb;101(2):614-23. doi: 10.1152/jn.90544.2008. Epub 2008 Nov 19.
Motor control relies on multiple sources of information. To estimate the position and motion of the hand, the brain uses both vision and body-position (proprioception and kinesthesia) senses from sensors in the muscles, tendons, joints, and skin. Although performance is better when more than one sensory modality is present, visuomotor adaptation suggests that people tend to rely much more on visual information of the hand to guide their arm movements to targets, even when the visual information and kinesthetic information about the hand motion are in conflict. The aim of this study is to test whether adapting hand movements in response to false visual feedback of the hand will result in the change or recalibration of the kinesthetic sense of hand motion. The advantage of this cross-sensory recalibration would ensure on-line consistency between the senses. To test this, we mapped participants' sensitivity to tilted and curved hand paths and then examined whether adapting their hand movements in response to false visual feedback affected their felt sense of hand path. We found that participants could accurately estimate hand path directions and curvature after adapting to false visual feedback of their hand when reaching to targets. Our results suggest that although vision can override kinesthesia to recalibrate arm motor commands, it does not recalibrate the kinesthetic sense of hand path geometry.
运动控制依赖于多种信息来源。为了估计手部的位置和运动，大脑利用视觉以及来自肌肉、肌腱、关节和皮肤中传感器的身体位置（本体感觉和动觉）感觉。尽管当存在多种感觉模态时表现会更好，但视觉运动适应表明，人们往往更依赖手部的视觉信息来引导手臂向目标移动，即使关于手部运动的视觉信息和动觉信息相互冲突。本研究的目的是测试响应手部的虚假视觉反馈而调整手部运动会是否导致手部运动动觉感觉的改变或重新校准。这种跨感觉重新校准的优势将确保各种感觉之间的在线一致性。为了测试这一点，我们绘制了参与者对倾斜和弯曲手部路径的敏感度，然后检查响应虚假视觉反馈而调整他们的手部运动是否会影响他们对手部路径的感觉。我们发现，参与者在适应手部虚假视觉反馈以触及目标后，能够准确估计手部路径方向和曲率。我们的结果表明，尽管视觉可以超越动觉来重新校准手臂运动指令，但它不会重新校准手部路径几何形状的动觉感觉。
