Mind & PerceptionNeuroscience

How Fast Are You?

Reacting to a light takes about a quarter of a second

A friend drops a dollar bill between your open fingers. You are staring right at it. So why do your fingers close on nothing?

You'll find out

  • How long your own reaction takes
  • Where those milliseconds go
  • What that delay costs on a highway

Why it matters

Your reaction time rides along whenever you drive, cross a street or grab a falling glass. It pays to know its size.

About 3 min6 interactive slides · 5 questionsLesson 118 · Zone 14

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