Balance is maintained by the interactions in the brain of nerve impulses from the inner ear, the eye, the neck muscles, and the muscles and joints of the limbs. Balance requires the interaction between many different organs and systems in the body. Input comes from three main areas:
- Vision gives important information to the balance center of the brain regarding movement and our surroundings.
- The balance portion of the inner ear gives the brain information about movement of our head.
- Proprioception is the information coming from our feet and our joints (neck) about our postural position in our environment.
A disturbance in any of these areas may result in the sensation of dizziness or unsteadiness. General disturbances of body function (blood pressure, blood chemistry changes, brain function) may also lead to dizziness by interfering with coordination of the impulses of the brain.
It’s important to understand the terms associated with dizziness and vertigo:
Vertigo – The feeling that you or your surroundings are moving or spinning.
Imbalance – Inability to keep one’s balance especially when standing and walking. Often there is a feeling of being wobbly and unstable.
Lightheadedness – The feeling of nearly passing out, similar to the feeling you might have if you hold your breath for a long time.
Dizziness – A general term for all symptoms of balance and instability.
The terms vertigo and dizziness are often confused. Vertigo refers to when patients experience an abnormal sensation of movement, generally a spinning or rotation of the surrounding environment or of the body. Dizziness refers to a feeling of imbalance, lightheadedness, blacking out, staggering, disorientation, weakness and other sensations.
Dizziness and imbalance can be grouped into types by the portion of the entire balance system that is not working properly.
Symptoms can range from mild and brief to more severe sensations accompanied by nausea. It is helpful to characterize the symptoms clearly so an accurate diagnoses may be achieved.
Common disorders causing vertigo include benign paroxysmal positioning vertigo (BPPV), vestibular neuritis, migraine associated vertigo and Meniere’s disease. Imbalance and disequilibrium include central dizziness, persistent postural perceptual disequilibrium (PPPD), cervical dizziness and post-concussive. Many forms of balance disorders do not involve the inner ear but are able to be treated. After diagnosing the problem various treatment modalities including medical, surgical, and vestibular rehabilitation can improve overall balance function.