Control of goal-directed movements within (or beyond) reach?
Control of goal-directed movements within (or beyond) reach?
复制标题
控制目标导向的运动在（或超出）范围内？
DOI：
10.1016/j.plrev.2019.03.016
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发表时间：
2019
影响因子：
11.7
通讯作者：
Hogan, Neville
中科院分区：
文献类型：
--
作者：
Sternad, Dagmar;Hogan, Neville
大约 40 年前，Morasso [1] 的一项开创性研究为随后的运动神经科学研究奠定了基础：指向水平面上的目标显示出一致平滑的直线手部轨迹，而相应的关节角度轨迹缺乏不变性。这一结果首次表明，外部空间的位置决定了关节的募集和配置，而不是相反——与异向中心主义的认知概念平行的运动[2, 3]。考虑到多一映射，这种从外部坐标到关节坐标的反转需要某种形式的身体表示——“内部模型”。在接下来的几十年里，许多研究都致力于“充实”这个内部模型。它的存在通过对外部施加的力场 [4] 和视觉扭曲 [5] 的感觉运动适应的优雅研究得到了证明。许多正在进行的后续研究仍然停留在“平坦的土地”上，将手臂运动限制在水平面上，经常通过限制手臂和前臂的运动来消除冗余[6-8]。虽然简化的实验限制了人类运动普遍存在的变异性，以促进数学建模和神经成像，但这些高度控制的运动与人类在日常活动中所做的事情相去甚远。难道“婴儿与洗澡水一起被倒掉了”？真正的挑战是否被无意中消除了？
About 40 years ago a seminal study by Morasso [1] set the stage for much of the ensuing research in motor neuroscience: pointing to targets in the horizontal plane revealed consistently smooth straight-line hand trajectories, while the corresponding joint angle trajectories lacked invariance. This result was the first to show that locations in extrinsic space determined the recruitment and configuration of joints, rather than the other way around—a motor parallel to the cognitive concept of allocentrism [2, 3]. Given the many-toone mapping, such inversion from external coordinates to joint coordinates necessitates some form of representation of the body—an ‘internal model’.In subsequent decades many lines of research strove to ‘flesh out’this internal model. Its existence was demonstrated by elegant studies of sensorimotor adaptation to externallyimposed force fields [4] and visual distortions [5]. A host of subsequent studies, many ongoing, remained in ‘flat land’, constraining arm movements to a horizontal plane, frequently eliminating redundancy by confining motion to arm and forearm [6–8]. While simplified experiments constrain the ubiquitous variability of human movements to facilitate mathematical modeling and neuroimaging, these highly-controlled movements are a far cry from what humans do in day-to-day activities. Was “the baby thrown out with the bathwater”? Were the real challenges inadvertently removed?