Appliance Of Science: Why do we feel dizzy when we spin around?

We’ve all had that feeling at some stage as we step off fast amusement park ride, or simply spin around for fun; that feeling of dizziness and disorientation and finding it difficult to stay upright. But why do we feel dizzy when we spin?

It’s all in the ears

Surprising as it might seem, the answer to our dizziness can be found inside our ears. The inner ear contains a sensory system called the vestibular system, a set of three semi-circular canals, each at 90 degree angles to each other.

The vestibular system helps orientate us in space.

The semi-circular canals are filled with a thick fluid called endolymph and a gel filled structure called the cupula. The cupula contains a layer of tiny hairs.

How you move

As we move around, the fluids inside the semi-circular canals move too.

This flow of movement makes the tiny hairs inside the cupula move.

The direction that the hairs move depends on what way the fluids are moving, which of course depends on what direction our head is moving.

The tiny hairs are attached to nerve endings so when they move, these nerves send signals to our brains telling it what direction we are moving.

Add in the eyes

Our eyes also respond to rapid spinning movement. When our head starts to move in one direction our eyes automatically move in the opposite direction, to allow us keep our focus.

However, when we spin, our eyes have reached their limit of rotation before our head has completed a full 360-degree spin. T

o counteract this, our eyes tend to flick back to a new starting position mid-spin, and this happens repeatedly as we keep spinning.

This repetitive eye movement, called nystagmus, can also contribute to the dizzying sensation.

Can we avoid getting dizzy when we spin?

For most of us, there is little we can do about the dizziness caused by an occasional spin, except to let it pass, which it usually does very quickly. For others — such as figure skaters, certain athletes, and dancers like ballerinas — spinning is part of their training or profession.

When spinning is an occupational regularity, there are a few tricks that can be practiced to help reduce the dizzy side-effects.

Ballerinas can use a technique called spotting, whereby they hold their gaze on a fixed point, keeping their head in place while the rest of their body spins. They then spin their head at the last possible second, bringing it around to complete the spin with the rest of the body before starting the process again.

This technique reduces the amount of overall spinning of the head and eye movement, thereby reducing the overall dizzying effects.

Other athletes find that they can reduce dizziness by maintaining a steady speed. The effects are felt most when speeding up or slowing down, so keeping these speed changes to a minimum can help.

A final technique that is practiced by figure skaters in particular is something called optokinetic nystagmus. This is effectively the opposite of nystagmus.

It involves training the eyes to move slowly to track a moving object and then rapidly reposition to a different point on the object, returning to the continued slow tracking again.

This reduces the rapid back-and-forth movement of the eyes, and gives the body a sense of stability in movement.