Rapos Victoria, Cinelli Michael
Department of Kinesiology and Physical Education, Wilfrid Laurier University, 75 University Ave, W. Rm. 501, Waterloo, ON, Canada.
Exp Brain Res. 2020 Feb;238(2):513-523. doi: 10.1007/s00221-020-05732-y. Epub 2020 Jan 21.
Individuals constantly adapt their locomotion to navigate through complex environments. However, little known about anticipatory strategies used by children during adaptive locomotion. The purpose of this study was to compare the effects of manipulating visual and somatosensory information during a multiple obstacle crossing task between children and adults. It was hypothesized that compared to young adults, children would have difficulty with anticipatory motor planning and online control during a multiple obstacle crossing task when sensory information was manipulated. Children (N = 16, [Formula: see text] = 9 ± 1.07 years) and young adults (N = 16, [Formula: see text] = 22 ± 0.96 years) walked along a 7 m pathway towards a goal while avoiding stepping on one, or two virtual obstacles placed 5 m from the start. Visual information regarding the number of obstacles was either presented at the start of steady-state locomotion, or two steps prior to the first obstacle. Each participant completed 36 trials, 18 on flat ground and 18 on foam terrain. Results indicated that in comparison to young adults, children's foot positions were significantly closer to the first obstacle when visual information about the obstacle was delayed. On flat ground, children demonstrated similar Trail foot positions relative to the first and second obstacles, suggesting children planned for the avoidance of the obstacles separately. On foam terrain, children performed similar to young adults, such that their Trail foot position relative to the first obstacle was significantly closer to the obstacle compared to their Trial foot position relative to the second obstacle. The results suggest that children plan for the avoidance of multiple obstacles differently compared to young adults. When stability is challenged, maintaining forward progression of locomotion overrides the planning of obstacle crossing, such that children perform similar to young adults. Therefore, it appears that children have difficulties with online control and anticipatory motor strategies during a multiple obstacle crossing task.
个体不断调整其运动方式以在复杂环境中导航。然而，对于儿童在适应性运动中所采用的预期策略却知之甚少。本研究的目的是比较在多障碍物穿越任务中，操纵视觉和躯体感觉信息对儿童和成年人的影响。研究假设，与年轻成年人相比，当感觉信息被操纵时，儿童在多障碍物穿越任务中的预期运动计划和在线控制会存在困难。儿童（N = 16，[公式：见正文] = 9 ± 1.07岁）和年轻成年人（N = 16，[公式：见正文] = 22 ± 0.96岁）沿着一条7米的路径走向一个目标，同时避免踩到距离起点5米处放置的一个或两个虚拟障碍物。关于障碍物数量的视觉信息要么在稳态运动开始时呈现，要么在第一个障碍物之前两步呈现。每位参与者完成36次试验，18次在平地上，18次在泡沫地形上。结果表明，与年轻成年人相比，当关于障碍物的视觉信息延迟时，儿童的脚位置明显更靠近第一个障碍物。在平地上，儿童相对于第一个和第二个障碍物的轨迹脚位置相似，这表明儿童分别计划避开障碍物。在泡沫地形上，儿童的表现与年轻成年人相似，即他们相对于第一个障碍物的轨迹脚位置比相对于第二个障碍物的轨迹脚位置明显更靠近障碍物。结果表明，与年轻成年人相比，儿童计划避开多个障碍物的方式有所不同。当稳定性受到挑战时，保持运动的向前推进优先于穿越障碍物的计划，因此儿童的表现与年轻成年人相似。因此，在多障碍物穿越任务中，儿童在在线控制和预期运动策略方面似乎存在困难。
