Graduate School of Social and Cultural Sciences, Kumamoto University, 2-40-1 Kurokami, Kumamoto, 860-8555, Japan.
Graduate School of Humanities and Social Sciences, Kumamoto University, 2-40-1 Kurokami, Kumamoto, 860-8555, Japan.
Exp Brain Res. 2021 Jan;239(1):257-265. doi: 10.1007/s00221-020-05966-w. Epub 2020 Nov 4.
Peripersonal space (PPS), which refers to space immediately around an individual's body, plays an important role in interacting with external objects and avoiding unsafe situations. Studies suggest that, during self-motion perception, PPS expands in the direction in which a person perceives himself/herself to be traveling. In the present study, we built on this by investigating, using visually induced self-motion (vection), how visual self-motion information modulates PPS representation. In our experiment, large-field visual motion was presented through a head-mounted display that caused observers to perceive themselves as moving forward in a tunnel (LF condition). To clarify the effects of self-motion information, we compared the findings for this condition with those of another condition, in which small-field visual motion was presented; here, only the central visual field represented motion, which caused the observers to perceive relatively little self-motion (SF condition). Two speeds were tested for both conditions: 1.5 m/s and 6.0 m/s. For measurement, we used a visuotactile-interaction task in which participants, while observing a visual probe object approaching from various distances, were instructed to press a response key as soon as they detected tactile stimuli delivered to their chest. We measured the distance at which the visual approaching probe object facilitated tactile detection (visual-facilitation effect); this was determined through comparisons with trials when no probe was presented. The results showed that the visual facilitation effects were observed for larger distance in the LF than SF conditions, irrespective of tested speeds. These results suggest that visual self-motion information can modulate PPS representation. This finding fits well with the view that PPS representation contributes to protecting the body from potential threats in the environment.
个体周围空间（PPS）是指个体身体周围的空间，它在与外部物体交互和避免不安全情况方面起着重要作用。研究表明，在自我运动感知过程中，PPS 在人感知自身运动的方向上扩展。在本研究中，我们通过使用视觉诱导的自我运动（视动）来研究视觉自我运动信息如何调节 PPS 表示，在此基础上进行了进一步的研究。在我们的实验中，通过头戴式显示器呈现大视野视觉运动，使观察者感觉到自己在隧道中向前移动（LF 条件）。为了阐明自我运动信息的影响，我们将该条件下的结果与另一种条件下的结果进行了比较，在另一种条件下，小视野视觉运动被呈现；在这里，只有中央视野代表运动，这导致观察者感觉到相对较少的自我运动（SF 条件）。对于两种条件，我们测试了两种速度：1.5 m/s 和 6.0 m/s。对于测量，我们使用了一种视触互动任务，在该任务中，参与者在观察视觉探测物体从不同距离接近时，被指示在感觉到触觉刺激传递到他们的胸部时按下响应键。我们测量了视觉接近探测物体促进触觉检测的距离（视觉促进效应）；这是通过与没有探测物体呈现的试验进行比较来确定的。结果表明，在 LF 条件下，无论测试速度如何，较大距离的视觉促进效应都比 SF 条件明显。这些结果表明，视觉自我运动信息可以调节 PPS 表示。这一发现与 PPS 表示有助于保护身体免受环境中潜在威胁的观点非常吻合。
