Seeing Without Sight

Seeing Without Sight | Psychology Today: "Neuroscientists used to think that vision is organized in a simple, hierarchical fashion. The brain's first-stop visual processing center was thought to receive an exact duplicate (in neural terms) of light patterns that fall on the retina of the eye. Then, through a series of steps involving ever-higher processing centers, the brain was thought to integrate discrete bits of information on angle, line, form, orientation, and hue until a conclusion could be drawn. For instance, the brain might receive neural signals that coded for red, round, shiny, and solid and then subsequently combine that information into recognition of an apple. In accordance with that 'bottom-up' model, the brain's first input center for visual information was aptly named V1. Higher visual processing centers were named V2, V3, and so on."