Final answer:
Negative afterimages are caused by neuronal adaptation and are explained by the opponent-process theory. The central nervous system's regulation of retinal ganglion cell activity influences how quickly these images fade, revealing insights into sensory perception and visual function.
Step-by-step explanation:
Negative afterimages are induced by the mechanism of neuronal adaptation, where prolonged staring at a particular color fatigues the retina's receptors and causes heightened activity in the oppositely responsive cells. When the gaze is shifted to a blank surface, an afterimage appears in the complementary color due to the overstimulation of specific retinal ganglion cells.
The opponent-process theory explains this phenomenon by suggesting that certain colors are linked within the visual system. For example, cells that are excited by green are inhibited by red, and vice versa. When green-receptive cells fatigue and their activity decreases upon looking away from the green dot, the red-receptive cells temporarily dominate, creating the perception of a red afterimage.
Central regulation plays a role in how quickly these afterimages decay. The nervous system is involved in returning the overstimulated cells to their baseline state. The faster the central nervous system can modulate this activity, the quicker the afterimage will fade. Understanding afterimages and the processes involved can shed light on broader aspects of sensory perception and visual function.