Department of Psychology, School of Education, Soochow University, Suzhou, Jiangsu, China.
Hum Brain Mapp. 2020 Aug 1;41(11):3009-3018. doi: 10.1002/hbm.24993. Epub 2020 Mar 23.
Two identical visual disks moving toward each other on a two-dimensional (2D) display are more likely to be perceived as "streaming through" than "bouncing off" each other after their coincidence. However, either a brief auditory tone or visual flash presented at the coincident moment of the disks can strikingly increase the incidence of the bouncing percept. Despite the neural substrates underlying the sound-induced bouncing effect have been widely investigated, little is known about the neural mechanisms underlying the flash-induced bouncing effect. The present study used event-related potential recordings to explore the temporal dynamics of the flash-induced bouncing effect. The results showed that the amplitude of the postcoincidence parietooccipital P2 component (190-230 ms after coincidence) elicited by the visual motion was significantly smaller on bouncing relative to streaming trials only when the flash was presented but not when absent. In addition, the parietal P3 component (330-430 ms) was found to be larger on bouncing than streaming trials when the flash was presented, but the opposite was true when no flash was presented. These electrophysiological findings suggest that the flash-induced bouncing effect may occur at both perceptual and postperceptual stages of processing.
当两个相同的视觉圆盘在二维（2D）显示器上相向移动，在它们重合后，相比于彼此弹开，人们更倾向于将它们感知为“穿过”彼此。然而，无论是在圆盘重合的瞬间呈现一个短暂的听觉音或视觉闪光，都可以显著增加弹开感知的发生率。尽管声音引起的弹开效应的神经基础已经被广泛研究，但对于闪光引起的弹开效应的神经机制知之甚少。本研究使用事件相关电位记录来探索闪光引起的弹开效应的时间动态。结果表明，当闪光呈现时，相对于流型试验，视觉运动引起的后重合顶枕部 P2 成分（重合后 190-230 毫秒）的振幅显著减小，但当没有闪光呈现时则没有这种减小。此外，当闪光呈现时，顶叶 P3 成分（330-430 毫秒）在弹开试验中比流型试验更大，但当没有闪光呈现时则相反。这些电生理发现表明，闪光引起的弹开效应可能发生在知觉和知觉后处理阶段。
