Sensory Modulation of Motor Patterns

运动反应可以被传入的感觉信息所改变。在这个奖项中，Kiisa Nishikawa博士将研究大脑如何使用传入的感觉输入来修改运动输出，使其适合当前环境。解决这一基本问题的方法将使用anuran喂养反应作为模型系统。关于与这些反应相关的神经回路，以及与猎物相关的刺激的感觉处理，我们已经知道了很多。然而，运动输出与感觉输入相匹配的过程仍有待阐明。当物体在视野中移动时，运动反应需要精确的感官识别和精确的定位。一旦这些识别和定位过程完成，大脑必须在正确的方向和正确的距离上产生适当的运动反应，而且反应必须在足够短的时间内发生，以确保捕获猎物。在这些实验中，与猎物捕获相关的感觉反馈系统将被描述为：(1)使用神经元示踪和免疫组织化学染色描述感觉受体的解剖结构及其中央投射；(2)利用背根和周围神经的细胞外记录来确定正常进食时的感觉活动模式；(3)通过脱传入和传入刺激实验阐明感觉输入如何调节运动输出。进食运动模式将通过高速摄像、肌电图和周围神经的细胞外记录来研究。这项研究将有助于了解适应性反应和感觉-运动整合的神经基础。

Motor responses can be modified by incoming sensory information. In this award, Dr. Kiisa Nishikawa will study the way in which the brain uses incoming sensory input to modify motor output so that it becomes appropriate to its current context. The approach for solving this fundamental problem will use anuran feeding responses as a model system. Much is already known about the neural circuits associated with these responses, and about sensory processing of stimuli associated with the prey object. However, the processes by which motor output is matched to sensory input remain to be elucidated. The motor responses require accurate sensory recognition and precise localization of the objects as they move through the visual field. Once these processes of recognition and localization have been carried out, the brain must produce an appropriate motor response oriented in the correct direction at the correct distance, and the response must occur within a time period short enough to insure prey capture. In these experiments, the sensory feedback systems associated with prey capture will be characterized by (1) describing the anatomy of sensory receptors and their central projections using neuronal tracing and immunohistochemical staining; (2) determining the pattern of sensory activity during normal feeding using extracellular recording from dorsal roots and peripheral nerves; (3) elucidating how sensory input modulates motor output using deafferentation and afferent stimulation experiments. Feeding motor patterns will be studied using high-speed videography, electromyography and extracellular recording from peripheral nerves. This study will contribute to an understanding of the neural basis of adaptive responses and sensory-motor integration.