Graduate School of Science and Technology, Meiji University, Kanagawa, Japan.
School of Science and Technology, Meiji University, Kanagawa, Japan.
Sci Rep. 2019 Jul 11;9(1):10030. doi: 10.1038/s41598-019-46527-8.
The robot hand illusion (RoHI) is the perception of self-ownership and self-agency of a virtual (robot) hand that moves consistently with one's own. The phenomenon shows that self-attribution can be established via temporal integration of visual and movement information. Our previous study showed that participants felt significantly greater RoHI (sense of self-ownership and sense of self-agency) when visuomotor temporal discrepancies were less than 200 ms. A weaker RoHI effect (sense of self-agency only) was observed when temporal discrepancies were between 300 and 500 ms. Here, we used functional near-infrared spectroscopy (fNIRS) to investigate brain activity associated with the RoHI under different visual feedback delays (100 ms, 400 ms, 700 ms). We found that the angular and supramarginal gyri exhibited significant activation in the 100-ms feedback condition. ANOVA indicated a significant difference between the 100-ms condition and the other conditions (p < 0.01). These results demonstrate that activity in the posterior parietal cortex was modulated by the delay between the motor command and the visual feedback of the virtual hand movements. Thus, we propose that the inferior parietal cortex is essential for integrating motor and visual information to distinguish one's own body from others.
机器人手错觉（RoHI）是指对与自身运动一致的虚拟（机器人）手的自我所有权和自我代理感的感知。这一现象表明，自我归因可以通过视觉和运动信息的时间整合来建立。我们之前的研究表明，当视觉运动时间差异小于 200ms 时，参与者会感到明显更强的 RoHI（自我所有权感和自我代理感）。当时间差异在 300 到 500ms 之间时，观察到较弱的 RoHI 效应（仅自我代理感）。在这里，我们使用功能近红外光谱（fNIRS）来研究在不同视觉反馈延迟（100ms、400ms、700ms）下与 RoHI 相关的大脑活动。我们发现，在 100ms 反馈条件下，角回和缘上回表现出明显的激活。方差分析表明，100ms 条件与其他条件之间存在显著差异（p<0.01）。这些结果表明，运动命令和虚拟手运动的视觉反馈之间的延迟调节了顶后皮质的活动。因此，我们提出，顶下皮质对于整合运动和视觉信息以区分自己的身体和他人的身体是必不可少的。
