Multilevel Dynamics of Conditional Control Mechanisms

描述：（申请人提供） 我们的大部分时间都花在做一些常规动作上， 和姿势定位。许多姿势和注视动作引起枢轴、弯曲， 或身体轴的位移。脑干的前庭神经核团 在感测这些轴向运动和调节轴向运动中 肌肉组织拟议研究的目标是构建总体 前庭神经核作为感觉运动整合单位的逻辑结构， 作为长期项目的一部分， 使用数学描述符进行控制。 因为前庭神经核特别负责轴向运动， 我相信轴向运动加上前庭神经核可以被看作是一种 前庭神经核在其中重组感觉神经的一个统一的多层次系统 支持特定运动阶段的信息。该系统与 其他神经中枢，如小脑，就像它与环境一样。 为了证明这个多级系统的性质，我们将开发一个 表征轴向感觉运动整合的数学框架 前庭神经核的运动。本提案侧重于运动 以近乎循环的方式重复。 第一个具体目标是数学上表征一系列的近循环 包括头部和躯干的轴向运动。比如说，目光移向 观看网球和乒乓球等比赛的特点是， 频率和幅度不同的运动范围。除了凝视和 扫描运动，近周期性运动包括保持躯干和头部 运动时的姿势和方向。第二个目标是扩大 从行为层面的数学表征，包括 前庭神经核中调节感觉运动的近周期过程 每个轴向运动范围的积分。因为， 前庭神经核可能有不同的范围，这两个特定的目的将是 重复直到数学框架表征统一的，多层次的， 整个系统的功能。 拟议的研究将阐明健康个体的轴向运动控制 和患者，沿着的感觉运动整合提供的 前庭神经核我们的研究集中在运动和机制的直接 临床相关性例如，前庭患者对 具体的动作。简单的任务，如杂货店购物，可以成为非常 在这些情况下，由于不平衡造成的困难， 结合了复杂的凝视活动--扫描杂货店的货架--和 平衡和运动。另一方面，头部运动被发现 在临床上帮助一组重要的前庭患者站立 平衡建立一个逻辑结构，将这些重复的 前庭核中类似的近周期过程的运动应该 促进我们对这些和其他鲜为人知的损伤的理解， 感觉运动整合

DESCRIPTION:(provided by applicant) Much of our time is spent performing routine movements that redirect our gaze and postural orientation. Many posture and gaze movements induce a pivot, bend, or displacement of the body axis. The vestibular nuclei of the brainstem play a key role in sensing these axial movements and in adjusting the axial musculature. The goal of the proposed studies is to construct the overall logical structure of the vestibular nuclei as a sensorimotor integration unit, as part of a long-term project to provide a functional interpretation of motor control using mathematical descriptors. Because the vestibular nuclei serve the axial movements in particular, we believe that the axial movements plus the vestibular nuclei can be viewed as a unified, multilevel system within which the vestibular nuclei recombine sensory information to support particular movement phases. This system interacts with other neural centers, such as the cerebellum, as it does with the environment. In order to demonstrate the nature of this multilevel system, we will develop a mathematical framework to characterize sensorimotor integration of axial movements by the vestibular nuclei. The present proposal focuses on movements that repeat in a nearly cyclic manner. The first Specific Aim is to mathematically characterize a range of near-cyclic axial movements involving the head and trunk. For example, the gaze shifts in watching such games as tennis and ping-pong will be characterized within a range of movements differing in frequency and amplitude. Besides gaze and scanning movements, near-cyclic movements include maintaining trunk and head posture and orientation during locomotion. The second Specific Aim is to extend the mathematical characterization from a behavioral level to include the near-cyclic processes in the vestibular nuclei that mediate sensorimotor integration of each range of axial movements. Because the processes in the vestibular nuclei may have different ranges, these two Specific Aims will be repeated until the mathematical framework characterizes unified, multilevel functions of the system as a whole. The proposed studies will clarify axial movement control in healthy individuals and patients, along with the sensorimotor integration provided by the vestibular nuclei. Our studies focus on movements and mechanisms of immediate clinical relevance. For example, vestibular patients respond strongly to specific movements. Simple tasks such as grocery shopping can become extremely difficult in these cases because of the disequilibrium resulting from a combination of an intricate gaze activity -- scanning grocery shelves -- with balance and locomotion. On the other hand, head movements have been found clinically to aid a significant group of vestibular patients with standing balance. The development of a logical structure linking such repetitive movements to similarly near-cyclic processes in the vestibular nuclei should advance our understanding of these and other poorly understood impairments of sensorimotor integration.