Hsieh P-J, Caplovitz G P, Tse P U
Department of Psychological and Brain Sciences, Moore Hall, H.B. 6207, Dartmouth College, Hanover, NH 03755, USA.
Neuroimage. 2006 Aug 15;32(2):728-39. doi: 10.1016/j.neuroimage.2006.03.047. Epub 2006 May 15.
The neural correlates of a recently discovered visual illusion that we call 'illusory rebound motion' (IRM) are described. This illusion is remarkable because motion is perceived in the absence of any net motion energy in the stimulus. When viewing bars alternating between white and black on a gray background, the percept alternates between one of flashing bars (veridical) and the IRM illusion, where the bars appear to shoot back and forth rather like the opening and closing of a zipper. The event-related functional magnetic resonance imaging (fMRI) data reported here reveal that (1) the blood-oxygen-level-dependent (BOLD) signal in the human analog of macaque motion processing area MT (hMT+) increases when there is a perceptual change from "no-IRM" to "see-IRM" and decreases when there is a perceptual change from "see-IRM" to "no-IRM," although the stimulus remains constant; and (2) the BOLD signal in early retinotopic areas (V1, V2, and V3d) shows switch-related activation whenever there is a perceptual change, regardless whether from IRM to no-IRM or vice versa. We conclude that hMT+ is a neural correlate of this novel illusory motion percept because BOLD signal in hMT+ modulates with the perception of IRM.
本文描述了一种最近发现的视觉错觉——“虚幻反弹运动”(IRM)的神经关联。这种错觉很显著,因为在刺激中没有任何净运动能量的情况下仍能感知到运动。当在灰色背景上观看黑白交替的条纹时,感知会在闪烁条纹(如实感知)和IRM错觉之间交替,在IRM错觉中,条纹似乎来回快速移动,就像拉链的开合。本文报告的事件相关功能磁共振成像(fMRI)数据显示:(1)尽管刺激保持不变,但当感知从“无IRM”变为“看到IRM”时,人类猕猴运动处理区域MT(hMT+)类似物中的血氧水平依赖(BOLD)信号增加,而当感知从“看到IRM”变为“无IRM”时,该信号减少;(2)每当有感知变化时,早期视网膜区域(V1、V2和V3d)中的BOLD信号都会显示出与转换相关的激活,无论这种变化是从IRM到无IRM还是相反。我们得出结论,hMT+是这种新型虚幻运动感知的神经关联,因为hMT+中的BOLD信号会随着IRM感知而调节。