Institute for Human Neuroscience, Boys Town National Research Hospital, 14090 Mother Teresa Lane, Boys Town, NE 68010, USA.
Structure and Motion Laboratory, Department of Comparative Biomedical Sciences, The Royal Veterinary College, University of London, Hatfield, Hertfordshire AL9 7TA, UK.
Biol Lett. 2023 Sep;19(9):20230260. doi: 10.1098/rsbl.2023.0260. Epub 2023 Sep 27.
Elephants are atypical of most quadrupeds in that they maintain the same lateral sequence footfall pattern across all locomotor speeds. It has been speculated that the preservation of the footfall patterns is necessary to maintain a statically stable support polygon. This should be a particularly important constraint in large, relatively slow animals. This suggests that elephants must rely on available sensory feedback mechanisms to actively control their massive pillar-like limbs for proper foot placement and sequencing. How the nervous system of elephants integrates the available sensory information for a stable gait is unknown. Here we explored the role that visual feedback plays in the control of the locomotor pattern in Asian elephants. Four Asian elephants ( walked with and without a blindfold as we measured their stride time intervals. Coefficient of variation was used to assess changes in the overall variability of the stride time intervals, while approximate entropy was used to measure the stride-to-stride consistency of the time intervals. We show that visual feedback plays a role in the stride-to-stride consistency of the locomotor pattern in Asian elephants. These results suggest that elephants use visual feedback to correct and maintain proper sequencing of the limbs during locomotion.
大象在大多数四足动物中是不同寻常的,因为它们在所有运动速度下都保持相同的横向顺序步态模式。有人推测,保持步态模式是维持静态稳定支撑多边形的必要条件。这在大型、相对缓慢的动物中应该是一个特别重要的限制因素。这表明大象必须依靠现有的感觉反馈机制来主动控制其巨大的柱状肢体,以实现正确的足部放置和顺序。大象的神经系统如何整合可用的感觉信息以保持稳定的步态尚不清楚。在这里,我们探讨了视觉反馈在亚洲象运动模式控制中的作用。我们让四只亚洲象(带着和不带着眼罩)行走,同时测量它们的步幅时间间隔。变异系数用于评估步幅时间间隔整体变异性的变化,而近似熵用于测量时间间隔的步幅间一致性。我们表明,视觉反馈在亚洲象的运动模式的步幅间一致性中起着作用。这些结果表明,大象在运动过程中使用视觉反馈来纠正和保持肢体的正确顺序。