Mind & PerceptionMotion Illusions

The Flash-Lag Illusion

Moving things look ahead of where they really are

A flash and a moving dot line up perfectly. So why does the dot look ahead, and why does that worry soccer referees?

You'll find out

  • What your eyes do with moving things
  • Three ideas about why it happens
  • How often referees get offside wrong

Why it matters

Catching, driving and refereeing all depend on where your brain puts moving things, which isn't always where they are.

About 3 min6 interactive slides · 5 questionsLesson 230 · Zone 26

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