Nystagmus is the medical term used to describe involuntary eye movements.
Most of the time the eyes will swing from side to side in a rapid, jerking motion that the person is unable to control. In other forms of this, the eyes actually move up and down rather than side to side.
Most people who are afflicted by this condition have had the condition from the time they were infants, and doctors say that roughly one in a thousand children will be born with involuntary eye movements.
There are 5 main types of Nystagmus:
Acquired is a type that is not actually present at birth, but rather comes on as the result of another disease.
Some diseases that have been known to bring about this include diabetic neuropathy, multiple sclerosis, and brain tumors. It can also be acquired after sudden trauma to the head or as a side effect from a certain medication used for a different purpose. Rarely, lesser reasons are the cause of sudden onset.
Flashing lights, hyperventilation, heavy vibrations, and nicotine have been recorded causes, although it doesn't happen very often at all. In fact, it's rare in general for this condition to occur after the early infant years.
Congenital is there from the time you're born. It's the most common type, and the eyes will usually swing from side to side in tandem. Sometimes this is misdiagnosed in infants as strabismus, which is simply when both eyes are unable to focus on the same thing at once.
Latent could come with any of the symptoms mentioned above, but it only happens when one eye is covered. Doctors aren't entirely sure how this comes about, but they theorize that it is because of the difference in incoming light when one of the eyes is covered up.
Manifest is the opposite of latent; it occurs at all times, whether one eye is covered or not.
Manifest-latent is a combination of the above two types. It is always present, but if you cover one eye the condition will worsen instantly.
Most of the time, nystagmus is the result of a neurological disorder early in life. As these people grow up, the condition will become less and less noticeable.
It will always be present, but the eye movements will not be as rapid or as “jerky.” These eye movements are always involuntary, leaving the person with absolutely no control over them. Adults who experience very few symptoms usually start to see a recurrence when they get tired or have a lot of stress.
Jerk nystagmus is another rarely seen type of this condition; it affects people who have problems with their inner ear. In this type, the eyes will slowly drift off towards one side and then suddenly jerk back the other way.
Most people who have this get sick and can even experience vertigo. Always go see a medical doctor if you begin to notice symptoms of this so that you can protect your eyesight as well as possible.