Journeys: Brain. Stop 6

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Let's test how fast your brain works. When the cup turns red, tap the hand quickly!

Too soon! Wait until the cup turns red.

The eyes saw it, the brain decided, a nerve passed the order to the hand, and all in less than a second!

And when something is very hot, the spinal cord pulls your hand away by itself, before you even think. That's a reflex.