What distinguishes positive afterimages from negative afterimages in visual perception?

The distinction between positive afterimages and negative afterimages is rooted in how our visual system processes overstimulation and color perception. Positive afterimages occur when you look at a bright object and then shift your gaze to a neutral area, resulting in a lingering image that retains the same color as the original stimulus. For example, if you stare at a bright red object and then look at a white surface, you may still see red.

In contrast, negative afterimages result from overstimulation of photoreceptors in the eye, particularly when you fix your gaze on a bright object for an extended period. This overstimulation leads to a temporary fatigue in those receptors, causing the visual system to generate a complementary color when the gaze shifts away from the bright object. For instance, if you look at a bright green object, the negative afterimage will appear in a shade of magenta, which is the complementary color of green.

Therefore, the option highlighting negative afterimages resulting from overstimulation and involving complementary colors accurately describes the mechanism. This understanding of how our visual system adapts and how colors interact in afterimages is crucial for grasping the concepts of visual perception and its physiological basis.