Tóth Tibor I, Daun Silvia
Department of Biology, Faculty of Mathematical and Natural Sciences, Heisenberg Research Group of Computational Neuroscience - Modeling Neuronal Network Function, University of Cologne, Koeln, Germany.
Jülich Research Center, Institute of Neuroscience and Medicine, INM-3, Koeln, Germany.
Physiol Rep. 2019 Apr;7(8):e14080. doi: 10.14814/phy2.14080.
Animal, and insect walking (locomotion) in particular, have attracted much attention from scientists over many years up to now. The investigations included behavioral, electrophysiological experiments, as well as modeling studies. Despite the large amount of material collected, there are left many unanswered questions as to how walking and related activities are generated, maintained, and controlled. It is obvious that for them to take place, precise coordination within muscle groups of one leg and between the legs is required: intra- and interleg coordination. The nature, the details, and the interactions of these coordination mechanisms are not entirely clear. To help uncover them, we made use of modeling techniques, and succeeded in developing a six-leg model of stick-insect walking. Our main goal was to prove that the same model can mimic a variety of walking-related behavioral modes, as well as the most common coordination patterns of walking just by changing the values of a few input or internal variables. As a result, the model can reproduce the basic coordination patterns of walking: tetrapod and tripod and the transition between them. It can also mimic stop and restart, change from forward-to-backward walking and back. Finally, it can exhibit so-called search movements of the front legs both while walking or standing still. The mechanisms of the model that enable it to produce the aforementioned behavioral modes can hint at and prove helpful in uncovering further details of the biological mechanisms underlying walking.
多年来直至如今，动物，尤其是昆虫的行走（运动）一直吸引着科学家们的广泛关注。这些研究包括行为学、电生理学实验以及建模研究。尽管收集了大量资料，但关于行走及相关活动是如何产生、维持和控制的，仍有许多问题尚未得到解答。显然，要实现这些活动，单条腿的肌肉群之间以及双腿之间需要精确协调：即腿内和腿间协调。这些协调机制的本质、细节及其相互作用尚不完全清楚。为了帮助揭示这些机制，我们运用了建模技术，并成功构建了一个竹节虫行走的六足模型。我们的主要目标是证明，只需改变几个输入或内部变量的值，同一个模型就能模拟多种与行走相关的行为模式以及最常见的行走协调模式。结果，该模型能够重现行走的基本协调模式：四足和三足模式以及它们之间的转换。它还能模拟停止和重新启动、从向前行走变为向后行走再变回来。最后，它能够在行走或静止时展现出前腿所谓的搜索动作。该模型产生上述行为模式的机制可以为揭示行走背后生物机制的更多细节提供线索并有所帮助。
