Horinouchi Takayuki, Ishida Haruki, Yang Kangjing, Li Jingnan, Morishita Takuya, Watanabe Tatsunori, Kirimoto Hikari
Department of Sensorimotor Neuroscience, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.
Japan Society for the Promotion of Science, Tokyo, Japan.
Front Hum Neurosci. 2024 Oct 2;18:1463220. doi: 10.3389/fnhum.2024.1463220. eCollection 2024.
In traffic rule, green/blue means go, and red means stop. It has been shown that this prior knowledge about traffic signal colors can affect reaction times (RTs). For example, RTs are longer when responding to a red "Go" signal and withholding the response to a blue "No-go" signal (Red Go/Blue No-go task) than when responding to a blue "Go" signal and withholding the response to a red "No-go" signal (Blue Go/Red No-go task), when responses are provided by button press. However, it remains unknown whether this holds in different actions. The aim of this study was to investigate the effect of prior knowledge of color on gait initiation in a Go/No-go task.
Seventeen participants performed Green Go/Red No-go and Red Go/Green No-go tasks, in which they stepped forward from a force plate in response to a green or red signal and withhold the response to red or green signal, respectively. We recorded the center of pressure (COP) and electromyogram (EMG) from the bilateral tibialis anterior muscles during gait initiation.
The onset of COP movement and toe-off time as well as COP displacements did not differ between the Go/No-go tasks. The EMG onset for the stance leg was delayed in the Red Go/Green No-go than Green Go/Red No-go task.
These findings suggest that the conflict between prior knowledge of color related to traffic rule and the meaning of the stimulus color affects muscle activity but not COP characteristics during gait initiation, highlighting two distinct motor control mechanisms, where the initial phase is influenced by cognitive load while the subsequent phase remains unaffected. This dissociation suggests that the later phase of gait initiation relies on robust spinal loops and central pattern generators, which are less influenced by cognitive factors such as prior knowledge.
在交通规则中，绿色/蓝色表示通行，红色表示停止。研究表明，这种关于交通信号颜色的先验知识会影响反应时间（RTs）。例如，当对红色“通行”信号做出反应并抑制对蓝色“禁止通行”信号的反应（红通/蓝禁任务）时，与对蓝色“通行”信号做出反应并抑制对红色“禁止通行”信号的反应（蓝通/红禁任务）相比，通过按键做出反应时，反应时间更长。然而，在不同的动作中这是否成立仍不清楚。本研究的目的是调查颜色先验知识对“通行/禁止通行”任务中步态起始的影响。
17名参与者执行绿色通行/红色禁止通行和红色通行/绿色禁止通行任务，在任务中他们分别根据绿色或红色信号从测力板向前迈步，并分别抑制对红色或绿色信号的反应。我们记录了步态起始期间双侧胫前肌的压力中心（COP）和肌电图（EMG）。
“通行/禁止通行”任务之间，COP移动的起始、离地时间以及COP位移没有差异。与绿色通行/红色禁止通行任务相比，红色通行/绿色禁止通行任务中支撑腿的EMG起始延迟。
这些发现表明，与交通规则相关的颜色先验知识和刺激颜色的含义之间的冲突会影响步态起始期间的肌肉活动，但不会影响COP特征，这突出了两种不同的运动控制机制，其中初始阶段受认知负荷影响，而后续阶段不受影响。这种分离表明，步态起始的后期阶段依赖于强大的脊髓回路和中枢模式发生器，它们受诸如先验知识等认知因素的影响较小。
