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Involuntary oscillatory movement of the eyeballs.



an involuntary, rapid rhythmic oscillation of the eyeballs. The bilateral form of nystagmus is much more common than the unilateral form. Nystagmus can be lateral, rotatory, vertical, or diagonal, depending on the direction of the oscillations of the eyeball. The condition need not be pathological. For example, rotatory nystagmus can be induced in healthy persons who are revolving in a swivel chair, optokinetic nystagmus can result from fixing the eyes on moving objects, and caloric nystagmus can result when cold or warm water is poured into the ear.

Nystagmus is pathological when it results from a morbid condition in the vestibulocochlear nerve, in the vestibular nuclei of the brainstem, or in the labyrinth of the vestibular apparatus. Nystagmus can also result from a morbid process in the cerebellum, an inflammation of the inner ear, cerebrocranial traumas, infections and toxicoses of the brain, or neoplasms in the brain. In rarer cases, nystagmus is caused by eye diseases. Miner’s nystagmus is an occupational disease in miners who work with a pick under poorly illuminated and poorly ventilated conditions. Because these workers are constantly looking up or to the side, certain eye muscles become strained.

Nystagmus is treated by eliminating the underlying cause. In cases of miner’s nystagmus, the worker is transferred to jobs above the ground.


Tsimmerman, G. S. Klinicheskaia otonevrologiia. Moscow, 1952.


References in periodicals archive ?
Through the use of the two magnetic fields, a null point can be created which serves as a prime location for a pivot point, allowing the pig to move through bends in the pipeline.
This device starts at a null balance point and as a load is applied, the current required to drive the transducer coil back to that null point can be measured very precisely resulting in a weight sensor having usable resolution and display capability of 1:120,000.
It is our belief that the cellular infrastructure market is currently at the null point between the mass 3G spending by the world's carriers in the most developed countries, and the lower but still strong spending which is starting to occur by carriers in the developing countries.
Then, despite all our expectations, there was the ignominy of only two paltry votes for our 2018 World Cup bid and the annual embarrassment of being a null point nation in the Eurovision Song Contest.