Forebrain control of locomotion

描述(申请人提供)：在自然栖息地行走时，动物和人类必须精确控制脚部的移动和放置，以避免出现许多障碍和不规则性。虽然运动过程中肌肉收缩的基本顺序是由脊髓决定的，但通过考虑视觉信息来调整运动的是脊髓上中枢的活动。这个项目的总体目标是了解前脑的神经机制，这些机制参与了运动对环境视觉感知特征的适应。所有数据将从猫在实验室内行走获得，(1)在平坦的表面上，不需要视觉-运动协调(简单运动)和(2)沿水平梯子行走，在水平梯子上，需要视觉-运动协调，以便准确地将脚放在十字架上(复杂运动)。我们将记录运动和顶叶皮质以及运动丘脑中已识别神经元的活动。然后，我们将可逆地阻断这些神经元的各种输入，以了解这些输入对控制视觉引导步进的信号形成的贡献。在目标1中，我们将研究丘脑腹外侧区、顶区5区和GABAA皮质内机制在锥体束和丘脑运动皮质投射神经元简单和复杂运动相关活动形成中的作用。在目标2中，我们将研究丘脑网状核的活动，以及小脑外侧核和中间核的传入在丘脑腹外侧区形成简单和复杂的运动相关活动中的作用。这项拟议的研究将揭示前脑控制视觉引导运动的重要神经机制。这项研究可能会有重要的临床应用。在前脑中风患者中，运动障碍康复策略的选择在很大程度上取决于前脑对运动的直接控制与脊髓机制有关的作用的阐明。 这项拟议的研究将揭示前脑的神经机制，这些机制涉及运动对环境视觉感知特征的适应。这是大脑的一项重要运动功能。在前脑中风患者中，运动障碍康复策略的选择在很大程度上取决于对前脑在运动控制中的作用的阐明。

DESCRIPTION (provided by applicant): When walking in natural habitats, animals and humans must control the transfer and placement of their feet precisely in order to avoid numerous obstacles and irregularities. While the basic order of muscular contractions during locomotion is determined by the spinal cord, it is the activity of supraspinal centers that modifies locomotion by taking into account visual information. The overall aim of this project is to understand the neuronal mechanisms of the forebrain that are involved in adaptation of locomotion to the visually perceived features of the environment. All data will be obtained from cats walking inside an experimental chamber (1) on a flat surface where no visuo-motor coordination will be required (simple locomotion) and (2) along a horizontal ladder where visuo-motor coordination for an accurate foot placement on the cross-pieces will be required (complex locomotion). We will record the activity of identified neurons in motor and parietal cortex, and in motor thalamus. We will then reversibly block various inputs to these neurons to understand the contribution that these inputs make to the formation of signals for control of visually guided stepping. In Aim 1, we will study the roles of ventrolateral thalamus, parietal area 5, and GABAA intra-cortical mechanisms in the formation of simple and complex locomotion-related activity of pyramidal tract and thalamus projecting neurons of the motor cortex. In Aim 2, we will examine the activity of the reticular nucleus of thalamus and the role of inputs from lateral and interposed nuclei of cerebellum in the formation of simple and complex locomotion-related activity in ventrolateral thalamus. The proposed study will reveal important neuronal mechanisms of the forebrain for control of visually guided locomotion. The study may have significant clinical applications. In forebrain stroke patients, selection of rehabilitation strategies for locomotion deficits depends largely on an elucidation of the role of direct forebrain control of locomotion in relation to spinal mechanisms. The proposed study will reveal neuronal mechanisms of the forebrain, which are involved in adaptation of locomotion to the visually perceived features of the environment. This is a vital motor function of the brain. In forebrain stroke patients, selection of rehabilitation strategies for locomotion deficits depends largely on an elucidation of the role of forebrain in control of locomotion.