Nystagmus is the involuntary rhythmic movement of the eyes.
The common form is called jerk nystagmus which consists of two movements:
- a slow drift of the eyes
- a rapid corrective movement back to the point of fixation
The second form is called pendular nystagmus which consists of movement which occur at roughly the same velocity in both directions.
Nystagmus may be caused by:
- lesions in:
- labyrintine-vestibular system
- congenital abnormalities