How is balance controlled by the body?

That's a complex question, but we manage to balance partly because of those receptors in the ear. We sense how your head moves. We also manage to keep our balance right by our eyes. So when we actually open our eyes, our balance usually improves. But also, we receive lots of information from the sensors in our body, which are called proprioceptors, a difficult word, just to say the information that tells how your legs are positioned with respect to each other, with respect to the floor, with respect to the body. So those three senses, so to speak, eyes, ears and body, come together in the brain, and the brain sort of weighs in the different information and produces an answer. That answer can be, my balance is good or my balance is not good, and then, sort of, you'd have to know where the problem comes from.