Next stop in our tour of your sensory systems? VISION. With a little help from an optical illusion, we take a look inside your eyes to try to figure out how your sense of vision works -- and how it can be tricked.

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Chapters:
Introduction: Optical Illusions 00:00
How Does Light Work? 1:31
Structure of the Eye 2:31
Layers of the Eye: Fibrous, Vascular, and Inner Layers 3:33
The Retina 4:56
Rods and Cones 6:07
How do Optical Illusions Work? 7:15
Review 8:33
Credits 9:14

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