The area on the retina without photoreceptors that respond to light. An image that falls on this region is not seen. The optic nerve exits the retina at this location on its way to the brain.Related resources: Eric H. Chudler, Ph.D., of the University of Washington, offers two dramatic experiments which demonstrate the presence and effect of the blind spot. An explanation by Serendip, of Bryn Mawr. Another cross-section of the human eye. Also see afterimage, colorblindness, cross-section, gestalt, night blindness or nyctalopia, Op Art, optical, optical illusion, optical mixing, perception, peripheral vision, sight, stereoscopic vision, subliminal message or subliminal advertising, and visual qualities.