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Mind & PerceptionVisual Illusions

The Hollow Mask

Your brain refuses to see a face as hollow

A mask turns around, and its hollow back should cave in. Instead a face pops out at you. Who decided that?

You'll find out

  • Why a hollow face looks solid
  • How shading can lie about shape
  • Where your hand beats your eyes

Why it matters

Seeing is guessing. Knowing when the brain's guesses win over the facts helps you doubt what looks obvious.

About 3 min6 interactive slides · 5 questionsLesson 249 · Zone 28

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