VISUAL CONTROL OF LOCOMOTION

运动的视觉控制是基于光流场的检测 在移动的观察点产生的图案。这个项目将 继续从光流场的角度研究航向的感知， 这项研究通过检查光流的功能意义， 行走时步态和姿势的控制。一组感知的 实验将解决悬而未决的问题：（1）影响 表面纹理，阴影，3D结构和流场噪音 航向感知;（2）特定流场变量的重要性 对于平移和曲线航向的感知，以及（3） 在平移期间和在曲线期间的眼旋转的分解 运动第二组感知运动实验将试图映射 输出方向特定的，相位相关的控制关系， 光流变量和步态和姿势的运动参数。 受试者将观看投影在 半球形圆顶在跑步机行走，而他们的步态运动学 和动态监测。控制关系将使用四个 操纵类型：（1）光流场的突然扰动 诱导步态调整，（2）流动中的连续振荡 在行走过程中引起姿势摆动的场，（3）质的变化 从一类光流图案到另一类，例如平移到 曲线运动，以及（4）重新安排之间的关系， 光流模式和步态效应器。结果将有助于 有关视觉控制运动的基本知识，并将提供一个 理解感知运动和步态障碍的基础。

The visual control of locomotion is based on the detection of Optical flow patterns produced at a moving point of observation. This project would continue research on the perception of heading from optical flow and extend this research by examining the functional significance of optical flow for the control of gait and posture during walking. One set of perceptual experiments will address outstanding questions regarding: (1) the effects of surface texture, shading, 3D structure, and flow field noise on the perception of heading, (2) the importance of specific flow field variables for perception of translational and curvilinear heading, and (3) the decomposition of eye rotation during translation and during curvilinear movement. A second set of perceptual-motor experiments will attempt to map out directionally-specific, phase-dependent control relations between optical flow variables and the motor parameters of gait and posture. Subject will view large-field optical flow displays projected in a hemispherical dome during treadmill walking, while their gait kinematics and dynamics are monitored. The control relations will be tested using four types of manipulations: (1) sudden perturbations of the optical flow field that induce adjustments in gait, (2) continuous oscillations in the flow field that induce postural sway during walking, (3) qualitative changes from one class of optical flow patterns to another, e.g. translational to curvilinear movement, and (4) rearrangement of the relationship between the optical flow pattern and the gait effectors. The results will contribute to basic knowledge about the visual control of locomotion, and will provide a basis for understanding perceptual-motor and gait disorders.