Visual system

The visual system is the part of the nervous system which allows organisms to see. It interprets the information from visible light to build a representation of the world surrounding the body. The visual system has the complex task of (re)constructing a three dimensional world from a two dimensional projection of that world. The psychological manifestation of visual information is known as visual perception.

The human eye
The image projected onto the retina is inverted due to the optics of the eye.

The visual system includes the eyes, the connecting pathways through to the visual cortex and other parts of the brain. The illustration shows the mammalian system.

Introduction

This article mostly describes the visual system of mammals, although other "higher" animals have similar visual systems. In this case, the visual system consists of:

• The eye, especially the retina
• The optic nerve
• The optic chiasma
• The optic tract
• The lateral geniculate nucleus
• The optic tectum (superior colliculus)
• The optic radiation
• The visual cortex
• The visual association cortex

Different species are able to see different parts of the light spectrum; for example, bees can see into the ultraviolet,^[1] while pit vipers can accurately target prey with their infrared imaging sensors.^[2]