Force-Field Control in Frog Motor Behavior

最近的数据表明，四足脊椎动物的脊髓可能被组织成控制力场原的电路。我实验室的最新数据显示，脊椎蛙的原始时间动态在许多情况下似乎具有恒定的持续时间，包括快速在线轨迹修正。我们假设这个时间尺度是脊髓回路的一个保守特征。如果正确的话，这个由原始定义的时间尺度将影响脊柱轨迹的形成、运动学习以及脊柱和脊柱上系统之间的控制划分。为了详细检验这一假设，我们有三个具体目的：(1)我们将检验脊髓擦拭反射中轨迹形成的所有调整都可以理解为原语的相位和幅度的调节，而不是持续时间或时间动态的调节。(2)我们将验证作用于力场原语的个体和整体感觉反馈回路被组织起来以保持原语的时间动态的假设。(3)我们将测试来自髓质和被盖的下行控制如何招募和/或重组脊髓原语的时间属性，以建立适应性运动行为。我们的数据将涉及脊柱水平的轨迹形成、下行和脊髓运动控制回路的相互作用、神经重组、损伤后神经修复和康复策略的设计、神经假体的设计和生物形态机器人。

Recent data suggests the spinal cord of tetrapod vertebrates may be organized into circuits that control forcefield primitives. Recent data from my laboratory shows the temporal dynamics of primitives in spinalized frogs appear to have constant duration in many contexts, including rapid on-line trajectory corrections. We hypothesize this time scale is a conserved characteristic of the spinal circuits. If correct, this time scale defined by a primitive would impact on spinal trajectory formation, motor learning and the partitioning of control between spinal and supraspinal systems. To test the hypothesis in detail we have three specific aims: (1) We will test the hypothesis that all adjustments of trajectory formation in spinal wiping reflex can be understood as regulation of phase and amplitude of primitives but not the duration or temporal dynamics. (2) We will test the hypothesis that individual and ensemble sensory feedback circuits acting on force-field primitives are organized to preserve the temporal dynamics of primitives. (3) We will test how descending controls from medulla and tegmentum recruit and/or reorganize the timing properties of spinal primitives to build adaptable motor behaviors. Our data will bear on trajectory formation at the spinal level, interaction of descending and spinal motor control circuits, neural reorganization, design of neural repair and rehabilitation strategies following injury, design of neuroprostheses, and biomorphic robotics.