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Why Do You Feel Dizzy After Spinning Around?

Have you ever spun around and felt like the room kept spinning after you stopped?

That dizzy feeling starts inside your ear, in a system called the vestibular system.

Deep inside each ear are three tiny tubes filled with liquid, called semicircular canals.

When you spin, the liquid moves and pushes against tiny hair cells inside the tubes.

Those hair cells send your brain a signal about how you are moving.

When you suddenly stop, though, the liquid keeps moving for a few seconds.

It is like water that keeps swirling in a cup after you stop stirring it.

Your ear tells your brain, "You are still turning," but your eyes say, "You have stopped."

Your brain gets two different messages at once, and that confusion feels like dizziness.

Here is the surprising part: your ear only notices a change in speed.

A speed that never changes sends almost no signal, even if it is very fast.

That is why speeding up and slowing down make you dizzier than steady spinning.

Ballet dancers use this fact with a trick called "spotting."

They fix their eyes on one point, then snap their head around to find it again quickly.

This keeps their eyes still for longer, giving their brain a calmer signal.

Figure skaters use a different trick: they train their eyes to cancel the spinning feeling.

They also keep their spinning speed even, because a steady speed sends almost no signal.