Dizziness is a word that is often used to describe two different feelings. It is important to know exactly what you mean when you say “I feel dizzy,” because it can help you and your doctor narrow down the list of possible problems. Lightheadedness is a feeling that you are about to faint or “pass out.” Although you may feel dizzy, you do not feel as though you or your surroundings are moving. Lightheadedness often goes away or improves when you lie down. If lightheadedness gets worse, it can lead to a feeling of almost fainting or a fainting spell (syncope). You may sometimes feel nauseated or vomit when you are lightheaded. Vertigo is a feeling that you or your surroundings are moving when there is no actual movement. You may feel as though you are spinning, whirling, falling, or tilting. When you have severe vertigo, you may feel very nauseated or vomit. You may have trouble walking or standing, and you may lose your balance and fall. Although dizziness can occur in people of any age, it is more common among older adults. A fear of dizziness can cause older adults to limit their physical and social activities. Dizziness can also lead to falls and other injuries. Lightheadedness~It is common to feel lightheaded from time to time. Lightheadedness usually is not caused by a serious problem. It often is caused by a momentary drop in blood pressure and blood flow to your head that occurs when you get up too quickly from a seated or lying position (orthostatic hypotension). Vertigo occurs when there is conflict between the signals sent to the brain by various balance- and position-sensing systems of the body. Your brain uses input from four sensory systems to maintain your sense of balance and orientation to your surroundings. Vision gives you information about your position and motion in relationship to the rest of the world. This is an important part of the balance mechanism and often overrides information from the other balance-sensing systems. Sensory nerves in your joints allow your brain to keep track of the position of your legs, arms, and torso. Your body is then automatically able to make tiny changes in posture that help you maintain your balance (proprioception). Skin pressure sensation gives you information about your body’s position and motion in relationship to gravity.