Why does spinning cause dizziness

Your perception has become normalized to the rotation of your head, giving you the sense that you are still, and the world is rotating around you. You have halted the rotation of your semicircular canals. But because of inertia, the endolymph keeps spinning, resisting change yet again. As the fluid continues to move, it once again deflects the cupula — this time in the direction in which you were spinning moments before — and as the oozing cupula bends those hair cells, a signal of movement is transmitted to the brain.

You sense that you are moving, but you're not. And that's dizziness. Follow Natalie Wolchover on Twitter nattyover. In fact, it would be pretty hard to do anything. Instead, it all begins inside your ears. Way past the outer area that you can see, rests three semicircular canals think elbow pasta shape.

They are each situated at 90 degree angles of each other. The canals are lined with extremely tiny strands of hair. Inside each canal where you would normally find the cheese in your elbow-shaped mac n cheese meal , is two layers of thick gelatinous fluid.

Scientists call them endolymph and cupula. As you move around, these fluids slosh inside the ear canals. That sloshing hits those itty bitty strands of hair, making them move back and forth. Those hair movements are key. The ear picks up on what direction the hair cells are moving and uses nerve cells to send a signal to the brain with all of that information.

Once you stop moving, the fluids stop sloshing and the hairs no longer pick up movement and that alert signal to the brain halts. Skaters suppress the dizziness by learning how to counteract nystagmus with another type of eye movement, called optokinetic nystagmus. Optokinetic nystagmus occurs in the opposite direction of the nystagmus and allows us to track a moving object—such as a train whizzing by—with our eyes while our head remains in place.

As the first few cars of the train move out of view, our eyes jump back to their initial position to follow the next few, and the motion repeats.

Skaters can train themselves to engage this opposing eye movement when they rotate to offset the nystagmus and keep the world from spinning. Professional athletes employ a variety of other strategies to prevent dizziness, including maintaining a uniform speed. The sensors in our vestibular system can detect only changes in speed, so they fail to sense rotation that takes place at a steady pace.

If athletes can manage their speed, they encounter dizziness only while they accelerate into and slow down out of a spin. Ballet dancers employ another technique they call spotting. They hold it in place and then quickly whip it around at the end of each turn, minimizing the time their head is rotating and limiting any nystagmus.

Learning to spot may offer ballet dancers an even broader benefit: a study suggests that the training might teach their brain how to suppress dizzy signals at their origin, the inner ear. Despite these tricks, figure skaters and dancers still lose their balance sometimes, but here, too, intense practice comes in handy. If they rehearse and master graceful movements at the end of a spin, it can afford them the chance to recover after a brief dizzy spell.

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