Collaborative Research: Neural and mechanical bases of motor primitives in voluntary frog behavior

最后修改日期：08/01/08最后修改人：Kenneth C.Wang摘要运动的组织是一个复杂而困难的问题，部分原因是运动控制中的“自由度问题”。动物运动可能性的丰富性使其运动控制的选择变得复杂。然而，与目前的机器人不同，动物可以有效地处理它们的自由度。一只刚出生的角马幼崽在出生后几个小时内就和牛群一起走了。一只青蛙或一只乌龟，只用它的脊髓，就可以控制复杂的目标导向轨迹。如果受到干扰，脊髓也可以迅速纠正这种运动。有人争辩说，这些非凡的能力是模块化的，由一小组原语或运动积木构成。这些原语是如何产生和使用的，这是本项目的重点。模块化和运动基元的概念为脊柱运动系统的组织提供了有用的描述。模块化组织已被证明支持脊椎行为，并可能有助于“引导”运动学习。尽管如此，模块化在很多层面上都是有争议的。为了执行复杂的、自愿的行为，脊椎原始体可能需要被取代或增强。这个项目解决了青蛙猎物攻击行为中的这个问题，这是一个对动物至关重要的系统中的一种自愿和适应行为，并且在以前的模块化研究中也得到了很好的表征。从多学科的角度对猎物攻击的神经力学进行了研究。模块化组织在神经科学和行为中的重要性远远超出了生物运动控制，并在进化和认知心理学中产生了影响。生物战略和解决方案也与未来的技术和机器人技术高度相关。将使用一种基于Cosserat链元素的新方法来开发一个猎物打击的计算机模型。该模型将由一个由四名研究人员组成的团队开发：德雷克塞尔大学的Simon Giszter(神经生理学)和Jonathan Nissanov(解剖学、成像)，不列颠哥伦比亚大学的Dinesh Pai(计算机科学、生物力学建模)，以及北亚利桑那大学的Kiisa Nishikawa(神经力学)。冷冻显微镜将被用来详细重建牛蛙的感觉运动解剖结构。这些结构将使用基于链的方法进行建模，以纳入这一细节。利用这些数据对猎物打击的实验和模型分析将相互告知，以确定固定或自适应模块化机制的优点和局限性，以及在青蛙中使用的生物实施。

Last Modified Date: 08/01/08 Last Modified By: Kenneth C. Whang Abstract The organization of movement is a complex and difficult problem, in part because of a "degrees of freedom problem" in motor control. The richness of an animal's movement possibilities makes its choice of movement controls complex. However, unlike current robots, animals cope efficiently with their degrees of freedom. A newborn wildebeest calf walks with the herd within a few hours of birth. A frog or a turtle, using just its spinal cord, can control complex goal-directed trajectories. The spinal cord can also rapidly correct such movements if they are perturbed. It has been argued that these remarkable capacities are modular, constructed with small sets of primitives or motor building blocks. How such primitives arise and are used is the focus of this project. The concepts of modularity and motor primitives have provided useful descriptions of the organization of spinal motor systems. Modular organization has been shown to support spinal behaviors, and may help to "bootstrap" motor learning. Nonetheless, modularity is controversial at many levels. Spinal primitives might need to be supplanted or augmented in order to perform complex, voluntary behaviors. This project attacks this problem in frog prey strike behaviors, a voluntary and adapted behavior in a system that is fundamentally important to the animal, and has also been well characterized in previous studies of modularity. The neuromechanics of prey strike is examined from a multi-disciplinary perspective. The importance of modular organization in neuroscience and behavior extends well beyond biological motor control, with ramifications in evolutionary and cognitive psychology. Biological strategies and solutions are also highly relevant to future technologies and robotics. A computer model of prey strike will be developed using a novel approach based on Cosserat strand-elements. The model will be developed by a team of four investigators: Simon Giszter (neurophysiology) and Jonathan Nissanov (anatomy, imaging) at Drexel University, Dinesh Pai (computer science, biomechanical modeling) at the University of British Columbia, and Kiisa Nishikawa (neuromechanics) at Northern Arizona University. Cryoplane microscopy will be used to reconstruct bullfrog sensorimotor anatomy in detail. These structures will be modeled using a strand-based approach to incorporate this detail. Experimental and model analyses of prey strike using these data will inform one another to establish the benefits and limits of fixed or adaptive modular mechanisms, and the biological implementation used in frogs.