It is estimated that 80% of everything that is sent to the brain is sent by the eyes. The human eye is enormously complicated - a perfect and interrelated system of about 40 individual subsystems, including the retina, pupil, iris, cornea, lens and optic nerve. For instance, the retina has approximately 137 million special cells that respond to light and send messages to the brain. About 130 million of these cells look like rods and handle the black and white vision. The other seven million are cone shaped and allow us to see in color. The retina cells receive light impressions, which are translated to electric pulses and sent to the brain via the optic nerve. A special section of the brain called the visual cortex interprets the pulses to color, contrast, depth, etc., which allows us to see "pictures" of our world. Incredibly, the eye, optic nerve and visual cortex are totally separate and distinct subsystems. Yet, together, they capture, deliver and interpret up to 1.5 million pulse messages a milli-second! Nothing can relate or compare to its ingenuity.
View full topics