Visual System - Introduction

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 body
  • 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, while pit vipers can accurately target prey with their pit organs, which are sensitive to infrared radiation. The eye of a swordfish can generate heat to better cope with detecting their prey at depths of 2000 feet.

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