Visual Perception

Receptive cells which transduce light (generally considered to range from longwave infrared radiation to shortwave ultraviolet radiation) are widespread in animals. In higher animals light receptive cells are usually concentrated in a light receptive surface, the retina, and light is focussed on the retinal surface by a lens or lenses. The processing of light information is complex and involves filtering and enhancement of the image in several stages, beginning at the level of individual receptor cells and proceeding next to interactions among adjacent receptors. Image formation and pattern recognition are functions of the central nervous system.

Structure of visual receptors

Monochromatic versus Color vision. We often assume that animals see the world the same way we do. Nothing could be more wrong. One of the basic ways in which most animals differ from humans is in how their visual receptors respond to "color". What is color?

Under low levels of light, humans see in black and white, using receptors called rods. Cones

Edge effects and other interactions among receptors

Perception of polarization of light

Flicker fusion

Image formation and pattern recognition