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How We See

How We See

Author: Maria Tucker

This lesson will introduce you to the anatomy and physiology of the human visual system, its connection to the brain and how this system processes light.

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Terms to Know

The light sensitive parts of the retina that processes color and day vision.

Electromagnetic Radiation

Another name for light; the human eye is only sensitive to a portion of it, known as visible light.


The number of waves passing a certain point per second, measured in hertz.

Optic Nerve

Tissue that connects the retina to the visual cortex in the back of the brain.


A thin, transparent tissue at the back of the eye that contains light sensitive receptors called rods and cones.


The long, thin light sensitive parts of the retina that processes night vision.

Visual Cortex

The part of the brain which processes visual information from the retina, communicated via a network of nerve cells.


The measure of the distance from two consecutive waves crests or troughs, common measured in nanometers.