From Jamie Cahill
The inner ear contains three fluid-filled tubes called semicircular canals. They work a bit like a biological spirit level. Fluid sloshes around the canals when you move, brushing past tiny hairs. As the hairs bend, they send messages to the brain telling it which way you are tilting. When you spin, the movement of the fluid catches up with the movement of your head and the hairs relax. When you stop spinning, the fluid keeps moving and the hairs bend in the opposite direction. This makes it feel like you’re spinning backwards, but your eyes tell your brain that you aren’t, and that’s what makes you feel dizzy.
Answered by Laura Mears for Brain Dump, How It Works issue 109
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