Why do humans have better equilibrium when steadily staring at an inert object/surface?


Why do humans have better equilibrium when steadily staring at an inert object/surface?

In: Biology

Balance is primarily controlled by the the inner ear however, vision is also used heavily to confirm what the ear is detecting. Closing your eyes for example, takes this confirmation away and makes it harder to maintain balance. If you are focusing on a moving object, your confusing your brain, your ear is saying “We’re not moving” while your eyes say “We’re moving”.

It’s similar to why some people get motion sickness, a disconnection between what the ear detects and what the eyes see make the brain think it was possibly poisoned. In the case of balance, the brain has difficulty figuring out which one to listen to (the ears or the eyes), which makes it hard to maintain proper balance. Focusing on a stationary object/surface helps keep your ears and eyes in agreement and makes balancing easier.

Genetics may play a role in an individuals ability to keep their balance in the absence of a fixed point of reference.

Take any person and have them walk across a gap, over a thin beam that is 6 inches off the ground, and most people will have little trouble with balance while doing so.

If you were to raise that beam up 100 feet off the ground, you would find that some people perform the same as they did on the ground and have no trouble keeping their balance, but other people would inexplicably start getting dizzy and losing their balance, even though at ground level they had no trouble walking on the beam.

It has to do with the balance systems in the brain taking input from your inner ear and merging/meshing them with cues from your eyes vision of the things around you. When you raise people off the ground, you remove the fixed points of reference that the brain needs in order to give context to the balance signals from the inner ear. When they are close to the ground, they can easily see the ground itself, and the horizon is closer. But the higher up you go, the farther out the horizon is, and you no longer have the ground as an easy and close reference. So the brain must rely more on the signals from the inner ear than on the visual system.

Some people are less affected by the loss of vision than others, and some people are highly dependent upon visual references. It has to do with your genetics.