A positive afterimage occurs when you look at a bright object for a period and then shift your gaze to a neutral background. Instead of fading away, the afterimage retains the same colors and brightness as the original object. This phenomenon happens because the photoreceptors in your eyes continue to send signals to your brain even after the stimulus is removed. This effect is different from a negative afterimage, where the colors are inverted. Positive afterimages can be seen with various objects, such as a bright light or a colorful painting. They are a result of the way our visual system processes and adapts to light stimuli.