Your nerves run at 400 km/h

When you decide to move a finger, or when you snatch it away from a flame, the signal races along your nerves at an astonishing speed: the fastest fibres carry the impulse at up to 120 metres per second, that is, more than 400 kilometres per hour.

That speed is possible thanks to myelin, an insulating sheath that wraps many nerve fibres and lets the signal leap from segment to segment instead of crawling through each one.

Thanks to this, you react to danger almost before you are aware of it: your hand has already left the fire by the time the pain is only beginning to register in your mind.

Source: Scientific American