Intentionally induced abnormalities in optokinetic pattern tests.

Abstract

Abnormalities of optokinetic nystagmus are easily detected by administering an optokinetic pattern test, in which optokinetic nystagmus responses to acceleration and deceleration of a series of optokinetic stimuli are recorded at slow paper speed, and the results are visually assessed based on the response pattern. Although optokinetic pattern tests are regarded as valuable in diagnosing lesions of the nervous system that directly or indirectly relate to the reflex route of optokinetic nystagmus, these tests can be significantly influenced by the intention of the person being tested. The present study revealed that the majority of abnormal optokinetic patterns can be induced intentionally. This indicates that optokinetic pattern tests are of limited diagnostic value, and a definite diagnosis should not be made based solely on the optokinetic pattern test result.