Flash-Lag Effect

The flash-lag effect, also called the flash-lag illusion, is a visual illusion in which a brief flash and a moving object that appear at the same location are perceived as displaced from one another. A moving object traveling along a continuous path tends to be seen as further along its trajectory than a flash presented at the same physical position and moment. The effect is generally explained by the delays inherent in neural visual processing, which cause the stationary flash to appear to lag behind the moving object even though the two occupied the same position when the flash occurred.