Nystagmus is an involuntary movement of the eyes - usually from side to side, but sometimes the eyes oscillate up and down or even in a circular motion. Most people with nystagmus have vision which is much worse than average - well below what is considered to be short sighted.
Many people can register as partially sighted and a small number can register as blind.
Nystagmus which appears in the first six months of life is called 'early onset nystagmus', or 'congenital' or 'infantile nystagmus'. The condition may also develop later in life when the term 'acquired nystagmus' is used. Nystagmus in early childhood may be caused by a defect in the eye or the visual pathway from the eye to the brain. It occurs in a wide range of eye disorders of childhood such as cataract, glaucoma, some disorders of the retina and albinism. It may also be found in children who have multiple disabilities such as Down's Syndrome.