University of Georgia, Athens, GA.
Bard College at Simon's Rock, Great Barrington, MA.
Nonlinear Dynamics Psychol Life Sci. 2022 Jan;26(1):21-43.
We describe the locomotion of Caenorhabditis elegans (C. elegans) using nonlinear dynamics. C. elegans is a commonly studied model organism based on ease of maintenance and simple neurological structure. In contrast to traditional microscopic techniques, which require constraining motion to a 2D microscope slide, dynamic diffraction allows the observation of locomotion in 3D as a time series of the intensity at a single point in the diffraction pattern. The electric field at any point in the far-field diffraction pattern is the result of a superposition of the electric fields bending around the worm. As a result, key features of the motion can be recovered by analyzing the intensity time series. One can now apply modern nonlinear techniques; embedding and recurrence plots, providing valuable insight for visualizing and comparing data sets. We found significant markers of low-dimensional chaos. Next, we implemented a minimal biomimetic simulation of the central pattern generator of C. elegans with FitzHugh-Nagumo neurons, which exhibits undulatory oscillations similar to those of the real C. elegans. Finally, we briefly describe the construction of a biomimetic version of the Izquierdo and Beer robotic worm using Keener's implementation of the Nagumo et al. circuit.
我们使用非线性动力学描述秀丽隐杆线虫（C. elegans）的运动。C. elegans 是一种常用的模式生物，易于维护且神经系统结构简单。与传统的需要将运动限制在 2D 显微镜载玻片上的微观技术不同，动态衍射允许作为衍射图案中单个点的强度时间序列来观察 3D 中的运动。远场衍射图案中任意点的电场是电场围绕蠕虫弯曲的叠加的结果。因此，可以通过分析强度时间序列来恢复运动的关键特征。现在可以应用现代非线性技术；嵌入和递归图，为可视化和比较数据集提供有价值的见解。我们发现了低维混沌的显著标记。接下来，我们使用 FitzHugh-Nagumo 神经元实现了 C. elegans 中央模式发生器的最小仿生模拟，该模拟表现出与真实 C. elegans 相似的波动振荡。最后，我们简要描述了使用 Keener 对 Nagumo 等人的电路的实现，构建 Izquierdo 和 Beer 机器人蠕虫的仿生版本。
