Quantitative measurement of smooth pursuit using a continuously changing sinusoidal wave in normal subjects.

In order to examine the frequency of a target wave and induced eye movements we designed and developed a new target wave (continuously changing sinusoidal wave). This target wave consisted of 20 sinusoidal waves from 0.1 to 2.0 Hz with 10 degrees amplitude (peak-to-peak amplitude is 20 degrees). Several parameters were calculated quantitatively with a microcomputer in normal subjects, and the following conclusions were obtained: The amplitude gain (peak-to-peak amplitude of eye movements/peak-to-peak amplitude of the target wave) and the retinal error velocity were appropriate parameters for representing the input and output of smooth pursuit. The limit of smooth pursuit was 1.2 Hz.