II. Standardization of the Eye-Tracking Test

Abstract

Standardization of the eye-tracking test, especially of the target velocity, is required for the purpose of comparing abnormalities of eye-tracking patterns recorded in different clinics. In consideration of the results of several good reports on target velocities, we have the following remarks: 1) The maximum velocity of a target which normal subjects can follow without delay of the eye movement is about 20°/sec. 2) When pursuit eye movements of normal subjects are registered with the aid of an electronystagmograph, the eye-tracking patterns will remain normal at target velocities of up to 45°/sec. 3) In order to detect abnormalities of pursuit eye movement with the aid of an electronystagmograph, the target velocity should be as fast as possible, but not exceeding 45°/sec. As an instrument for the examination of pursuit eye movements, for reasons outlined in the text, the Umeda circular eye-tracking test apparatus (amplitude 40°, frequency 0.33 Hz, and target velocity 42°/sec) is ideal. The target amplitude and technical problems in making the apparatus also are discussed.