CEREBAL CORTICAL CONTROL OF MOVEMENT

拟议研究的最终目的是增加我们对 运动皮质是如何控制运动并随后做出贡献的 为更好地治疗人类运动功能障碍而努力。具体目标 在接下来的几年里是为了阐明神经机制如何 外周感觉输入有助于自愿性运动的顺利执行 动静。已经证明，在两个电路之间存在闭合回路 运动皮质和外周，每个环都是特定的 特别的肌肉。最近的研究表明，这些回路起着一种 在自愿行动中发挥重要作用。至于神经机制 在这些电路中，我们提出了每个回路循环脉冲 在运动前和运动中增加神经元的兴奋性 与每一环相关联，即偏好偏向理论。这一假说将 通过慢性和急性实验进行检查。慢性实验 将使用食蟹猴进行实验。他们将接受培训，挑选 从旋转的食物板上抬起食物颗粒。那么一个封闭的密封室将是 安装在运动皮质上，运动皮质神经元的活动将 在拾音动作之前和过程中进行研究。分布情况 与规则运动位置相关的优先偏向神经元 相关神经元将被检查。环路中断的影响 这些优先偏置的电路也将被研究。急性 实验将使用猫进行。事实证明， 运动皮质神经元的外周诱发活动可被 来自感觉皮质的输入。修改模式将通过以下方式进行研究 将条件反射和测试刺激传递到感觉皮质和 丘脑。条件性刺激的效果将使用 以测试刺激诱发的单突触PSPs为指标。五花八门 将使用条件性刺激和测试刺激的组合。

The ultimate purpose of the proposed study is to increase our understanding of how the motor cortex controls movements and subsequently to contribute toward the better treatment of human motor dysfunctions. The specific aim during the coming years is to elucidate the neuronal mechanisms of how peripheral sensory input contribute to the smooth execution of voluntary movements. It has been shown that there are closed loop circuits between the motor cortex and the periphery and each loop is specific for a particular muscle. It has recently been shown that these circuits play an important role during voluntary movements. As for the neuronal mechanisms of these circuits, we have proposed that each loop circulates impulses before and during the movements to increase the excitability of neurons related to each loop, i.e., preferential bias theory. This hypothesis will be examined through chronic and acute experiments. Chronic experiments will be carried out using cynomolgus monkeys. They will be trained to pick up food pellet from rotating food board. Then a closed chamber will be installed over the motor cortex and activity of motor cortical neurons will be studied before and during the pick-up movements. Distribution of preferentially biased neurons in relation to location of regular movement related neurons will be examined. Effect of interruption of the loop circuits to these preferential bias will also be examined. Acute experiments will be carried out using cats. It has been shown that peripherally evoked activity of motor cortical neurons is modified by the input from the sensory cortex. The mode of modification will be studied by delivering conditioning and testing stimuli to the sensory cortex and the thalamus. The effect of conditioning stimuli will be examined using monosynaptic PSPs elicited by the test stimuli as indicators. Various combinations of conditioning and test stimuli will be used.