CRCNS US-German Research Proposal: Central Pattern Generators and Reflexive Feedback in Insect Locomotion: A Cross-Species Study

动物运动开始于中枢神经系统，并导致可量化的机械活动;因此，它为神经计算提供了一个很好的窗口，可以创建有意的行为并对环境条件做出反应。运动起源于中央模式发生器：脊椎动物脊柱和昆虫胸神经节中产生有节奏运动的神经网络。一些准备（如七鳃鳗，小龙虾）可以产生稳定的，接近周期性的节奏在隔离，其他人要么需要感官反馈，以产生功能步态或显着稳定。蟑螂和竹节虫这两个极端。它们具有相同的基本神经和生物力学结构，但前者在粗糙的地面上快速奔跑，而后者则适合在树枝和树叶上缓慢行走，具有不同的重力方向。利用现有的信息和收集新的数据，该项目将比较这些物种并解决以下问题：（1）前馈运动协调的功能组织是什么：驱动单个腿和关节的神经回路如何耦合以实现肢体间协调？(2)感觉输入在协调中的作用是什么：反馈如何影响运动模式，运动如何调节传入的感觉信息？(3)当动物改变速度、面对意想不到的扰动、以及在复杂地形上机动时，模式发生器和感觉反馈系统是如何被调节以产生适当的动作的？综合数学和计算模型的发展是回答这些问题的核心。新的数据将改进现有的模型，新的模型将被创建，以跨越从竹节虫到蟑螂的形态和行为范围，使我们能够阐明它们对不同环境的适应策略。这项研究将加深我们对动物和人类运动的产生和控制的理解。该项目的美国部分由数学科学部的数学生物学项目和综合有机系统部的神经系统集群共同资助。德国部分由德国教育和研究部（BMBF）资助。

Animal locomotion begins in the central nervous system and results in quantifiable mechanical activity; it therefore provides an excellent window into the neural computations that create intentional behaviors and respond to environmental conditions. Locomotion originates in central pattern generators: neural networks in the spines of vertebrates and thoracic ganglia of insects that produce rhythmic movements. Some preparations (e.g. lamprey, crayfish) can produce stable, near-periodic rhythms in isolation, others either require sensory feedback to produce functional gaits or are significantly stabilized by it. Cockroaches and stick insects exemplify these two extremes. They share the same basic neural and biomechanical architecture, but the former run rapidly over rough ground, while the latter are adapted for slow walking on twigs and leaves with varied orientations to gravity. Using existing information and collecting new data, this project will compare these species and address questions such as:(1) What is the functional organization of feedforward motor coordination: How are neural circuits that drive individual legs and joints coupled to achieve inter-limb coordination?(2) What is the role of sensory input in coordination: How does feedback affect motor patterns, and how does locomotion modulate incoming sensory information?(3) How are pattern generators and sensory feedback systems modulated to create appropriate actions as animals change speed, face unexpected perturbations, and maneuver to negotiate complex terrain?The development of integrated mathematical and computational models is central to answering such questions. New data will improve existing models, and new models will be created to span the morphological and behavioral ranges from stick insects to cockroaches, allowing us to illuminate their adaptive strategies to different environments. This research will deepen our understanding of the generation and control of locomotion, with general relevance to animals and humans.The US component of this project is jointly funded by the Mathematical Biology program in the Division of Mathematical Sciences and the Neural Systems Cluster in the Division of Integrative Organismal Systems. The German component is funded by the German Ministry of Education and Research (BMBF).