CRCNS: An Integrated Locomotion Model for Lamprey Swimming

描述(申请人提供)：运动是神经输出作用于肌肉的产物，在不可预测的环境中驱动机械复杂的身体。七鳃鳗是一种简单、研究充分、相对容易驯化的脊椎动物模型，可以用来探索这种神经机械系统。我们假设，在可预测的环境中，稳定的运动只需要中央模式发生器(CPG)，而不需要其他输入。我们还假设，在一个不可预测的环境中，感觉反馈和强烈的节段间耦合是必要的。为了研究这些假说，我们将与伦敦的Thelma Williams以及普林斯顿大学的研究人员菲利普·霍姆斯和亚历山大·史密茨一起开发一个综合的七鳃鳗游泳LAMPREYCOMP模型。该模型涵盖了CPG、感觉反馈、肌肉力学、身体力学和流体力学，是脊椎动物复杂行为的完整模型，尽管很简单。科恩和他的同事将对CPG及其对来自脊椎机械感受器、皮肤和侧线的感觉反馈的反应进行实验研究，并将开发LAMPREYCOMP组件，将感觉输入映射到运动神经输出。肌肉和身体力学方面的工作将由福尔摩斯和威廉姆斯完成。史密斯和霍姆斯将从实验和理论上研究游泳动物的流体力学。实验工作将包括开发一种名为P-Ray的机械模拟装置，它的运动将被调整，以重现活体动物的运动，从而能够测量流体运动和沿身体的压力变化。理论工作将包括与C.Peskin、L.Fuci和同事协商，开发LAMPREYCOMP的流体动力学组件。将对LAMPREYCOMP进行测试，以确保它重现整个动物游泳、各种减量准备和P-Ray的行为。然后，它将被用来研究操作的效果，比如从脊椎机械感受器中移除感觉反馈，这在实验上是不可能的。我们还证明了协议的所有组件都是可能的。因为七鳗鱼是所有脊椎动物运动的模型系统，我们的假设和模型将对更高级的生物体产生广泛的影响，在这些生物体中，目前还不可能有这样完整的方法。

DESCRIPTION (provided by applicant): Locomotion is the product of neural output acting on muscles driving a mechanically complex body in an unpredictable environment. The lamprey is a simple, well-studied and relatively tractable vertebrate model with which to probe this neuromechanical system. We hypothesize that steady locomotion in a predictable environment requires only the central pattern generator (CPG) without the necessity of other input. We also hypothesize that in an unpredictable environment sensory feedback combined with strong intersegmental coupling is necessary. To investigate these hypotheses we will develop an integrated model, of lamprey swimming LAMPREYCOMP with Thelma Williams, from London, and researchers Philip Holmes and Alexander Smits from Princeton University. The model spans CPG, sensory feedback, muscle mechanics, body mechanics, and fluid mechanics, and is a full model of a complex behavior in a vertebrate, albeit a simple one. Cohen and colleagues will perform experimental studies of the CPG and its response to sensory feedback from spinal mechanoreceptors, skin and lateral line and will develop the component of LAMPREYCOMP that maps sensory input to motor nerve output. Work on muscle and body mechanics will be done by Holmes and Williams. Smits and Holmes will study the fluid mechanics of the swimming animals both experimentally and theoretically. The experimental work will include developing a mechanical analog, P-RAY, whose motion will be adjusted to reproduce that of live animals, allowing measurements of fluid motion and pressure variations along the body. The theoretical work will include developing the fluid dynamical component of LAMPREYCOMP, in consultation with C. Peskin, L. Fauci and colleagues. LAMPREYCOMP will be tested to insure that it reproduces the behavior of whole animal swimming, various reduced preparations and P-RAY. It will then be used to investigate the effect of manipulations, such as removing sensory feedback from spinal mechanoreceptors that are not experimentally possible. We also show that all components of the protocol are possible. Because the lamprey is a model system for all of vertebrate locomotion, our hypotheses and models will have broad implications for more advanced organisms in which such a complete approach is not presently feasible.