ANALYSIS OF THE RECURRENT RENSHAW CIRCUIT

这项提议的总体目标是检验这样一个假设 脊髓反复抑制对运动神经元池活动的调节 在集中生成的活动期间接收公共命令，如 移动和抓挠。这个实验室最近的研究表明 运动中常见的运动活动模式决定了 反复抑制的分布。上面所述的假设 制定了将这些发现与其他重要特征相结合的方案 反复抑制的组织。有三个具体的 目标。第一个具体目标是比较经常性的组织 抑制和Ia在运动神经元池之间的相互抑制 控制脚踝。AIM-1研究将提供必要的数据以提供 反复抑制与Ia的组织结构的严格比较 对运动活动和组织模式的相互抑制 集中生成的马达指令。此信息将用于 为第二个特定目标检验假设。第二个具体问题 目的是测试一种假设，即运动神经元汇聚在一起 通过反复抑制相互连接接收共同的运动指令 在中央产生的运动活动期间。在这些研究中， 运动模式之间的互相关和相干函数 选定的后肢运动神经元池将在虚构的 移动和虚构的抓挠。接受公共服务的运动神经元池 运动指令，如相互关联和连贯性所示 功能，将与反复抑制和Ia的模式进行比较 运动神经元池之间的相互抑制。第三个具体目标 是为了检验这样一种假设，即反复的抑制会调节运动输出 在集中生成的运动活动期间，通过指导运动命令 到最活跃的机动车池。Ia反射的波幅和比率 将在虚构的过程中检查不同运动池的反应 AIM-3研究中的运动和抓挠。这些值将是 评估与已知的反复抑制模式和 单突触Ia投射。它们还将在以下情况下进行比较 应用胆碱能拮抗剂阻断复发抑制。 这项提议与健康相关的意义在于，这些研究 将提供有关通过反复抑制 运动神经元池中活动的相对程度。这条脊椎回路 受脊柱上中枢的控制，这可能会被中断 在疾病和脊柱损伤中，伴随着 对运动活动的调节。

The overall goal of this proposal is to examine the hypothesis that spinal recurrent inhibition regulates activity across motoneuron pools that receive common commands during centrally generated activities like locomotion and scratching. Recent work from this laboratory suggests that common patterns of motor activity during locomotion determine the distribution of recurrent inhibition. The hypothesis stated above has been formulated to integrate these findings with other important features of the organization of recurrent inhibition. There are three specific aims. The first specific aim is to compare the organization of recurrent inhibition and Ia reciprocal inhibition between motoneuron pools that control the ankle. Aim-1 studies will provide data necessary to provide a rigorous comparison of the organization of recurrent inhibition and Ia reciprocal inhibition to patterns of motor activity and the organization of centrally generated motor commands. This information will be used in testing the hypothesis for the second specific aim. The second specific aim is to test the hypothesis that motoneuron pools that are interconnected by recurrent inhibition receive common motor commands during centrally generated motor activities. In these studies, crosscorrelation and coherence functions between motor patterns of selected hindlimb motoneuron pools will be examined during fictive locomotion and fictive scratching. Motoneuron pools that receive common motor commands, as indicated by the crosscorrelation and coherence functions, will be compared to patterns of recurrent inhibition and Ia reciprocal inhibition between motoneuron pools. The third specific aim is to test the hypothesis that recurrent inhibition tunes motor output during centrally generated motor activities by directing motor commands to the most active motor pools. The amplitudes and ratios of Ia reflex responses in different motor pools will be examined during fictive locomotion and scratching in the Aim-3 studies. These values will be evaluated in relation to known patterns of recurrent inhibition and monosynaptic Ia projections. They will also be compared following the application of cholinergic antagonists to block recurrent inhibition. The health related significance of this proposal is that these studies will provide information about the regulation by recurrent inhibition of the relative degree of activity in motoneuron pools. This spinal circuit is subject to control from supraspinal centers, which may be interrupted in disease and spinal injury, with attendant deterioration in the regulation of motor activity.