Balance is the biomechanical ability to maintain the center of gravity of a body within the base of support with minimal postural sway. Keeping balance requires integration of inputs from multiple senses with the motor system responsible for muscle actions. The senses must detect the change of the body position and the information relayed to the muscular system, which make appropriate corrections when the limit of stability is reached.
How it works
Our sense of balance has a very important role in the lives of humans and animals. This sense takes place in an area that most people don't know, and that’s the ear. The sense of balance is two different senses: the Static equilibrium, and the Dynamic equilibrium. This is all apart of the vestibular system.
The Static equilibrium detects the movement of your head whether it be up, down, or side to side your body can tell what direction you are leaning based on the fluid in the semicircular canals. There are little microscopic hairs in each canal that senses the change, All are on a bulbed end in the canals. When you turn your head any direction you are then able to recognize the way you are turning because the fluid moves the top portion of the micro hairs that are installed in a jelly-like cupula.
The Dynamic equilibrium detects the linear or straight acceleration are detected by the organs called the utricle and saccule. They work similar to the way it is sensed with the first. The hair cells of the Otolithic organs are coated with a jelly-like liquid, but also have tiny calcium stones called Otoconia. When your body turns any direction other than straight, the tiny balls move over the hairs, causing them to bend. When you get dizzy by being spun around and then are stopped, you get the feeling that you are still spinning, that’s because the inertia of fluid is still moving in your ear. The equilibrium tells your cerebellum that you are spinning.
Your vision and skeletal system also have a lot to do with balance. When we are infants our bodies are being put to the test with our balance. Visual signals are sent to the brain about the body's position in relation to its surroundings. The vestibular system works with the visual system so that you can focus on objects while the head is turning.  
Balance disorders occur whenever there is a disruption in any of the vestibular, visual, proprioceptive or cognitive systems. All of which are described as a sensation of dizziness or vertigo, falling or a feeling of falling, lightheadedness or feeling woozy. Problems reading and difficulty seeing. Or disorientation. Some disorders are related to the ear while others are related to the brain. In relation to the ear a common reason of dizziness is due to a misplaced otoconia, which would give you the feeling of vertigo. Most commonly called BPPV (Benign Paroxysmal Positional Vertigo). The roaming otoconia can change the sense of movement, causing a difference between actual head movement and the message being sent to the brain by the inner ear. When trauma to the brain or ear occur they could lead to diseases or malfunctions in the balance system. Fluid in your ear might get released after head trauma which result in dizziness. Infections in the vestibular nerve and cochlear nerve can cause deafness and vertigo.
In some cases injections called Gentamicin are given in the ear canal. It affects the hair cells of the cochlea. In cases that do not respond to medical management, surgery may be indicated. Most cases can be cured using Vestibular rehabilitation to help make up for a loss or imbalance within the vestibular system. Its an exercise program designed by specially trained therapists that have an understanding of the vestibular system and its relationship with other systems in the body. Some cases are to sever and require surgery.  
How to improve balance
As you age, balance is slowly lost due to damaged sensory hairs. They are constantly being worn down by the noises of everyday life. Those hairs sense the direction your head is turning, and how fast you are going. Simple exercises everyday can help give more stability. Balance training repairs damaged pathways to the brain, strengthens weakened stabilizing muscles. yoga exercises on a BOSU or balance board test and pushes your body. You mind remembers this consistent training that is then transferred into everyday life. Balance not only helps you physically, but it has been proven that daily balancing exercises help increase energy and learning skills. Some schools allow for physical education class use balancing boards when studying.
- Los Angeles Times Health
- [The Human Body pg270-271 Dr.Jay L.]
- How Are Balance Disorders Treated?