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The Secret Life of the Brain
History of the Brain 3-D Brain Anatomy Mind Illusions Scanning the Brain The Episodes:

Mind Illusions
Movement Color Angles Form
Angles Study

In Zollner's illusion of direction, parallel lines appear crooked when lines at 45 degrees intersect them. The illusion vanishes when held far enough away from the eye to distinguish the short crossing lines.
Scientists are still confounded by the wonder of geometric illusions.



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