Vaziri-Pashkam Maryam, Cavanagh Patrick
Vision Sciences Laboratory, Department of Psychology, Harvard University, Cambridge, MA, USA; e-mail:
Iperception. 2011;2(9):1063-75. doi: 10.1068/i0435. Epub 2011 Dec 19.
When a brief flash is presented at the same location as a moving object, the flash is perceived to lag behind the moving object to an extent that increases with the speed of the object. Previous studies showed that moving objects appear faster at low luminance as a result of their longer motion trace. Here we examine whether this faster perceived motion also affects the amount of the flash lag at low luminance. We first verified that speed was overestimated at low luminance with our stimulus. We then asked subjects to align a briefly flashed dot with the moving target. Results showed that the flash-lag effect increased with physical speed at both high and low luminance, but there was no additional increase due to the perceived increase of speed at low luminance. We suggest that although motion blur contributes to perceived speed, it does not contribute to the speed information that influences its perceived position.
当一个短暂的闪光出现在与移动物体相同的位置时，闪光会被感知到在移动物体之后有一定延迟，且这种延迟程度会随着物体速度的增加而增大。先前的研究表明，由于移动物体的运动轨迹更长，在低亮度条件下它们看起来移动得更快。在此，我们研究这种更快的感知运动是否也会影响低亮度下的闪光滞后量。我们首先通过我们的刺激验证了在低亮度下速度被高估了。然后我们让受试者将一个短暂闪烁的点与移动目标对齐。结果表明，在高亮度和低亮度下，闪光滞后效应都随着物理速度的增加而增加，但在低亮度下，由于感知到的速度增加并没有额外的增加。我们认为，尽管运动模糊有助于感知速度，但它对影响其感知位置的速度信息没有贡献。
