Electronystagmograms of the eye tracking test, that is, eye tracking patterns were quantitatively assessed in 63 subjects. Abnormal findings consisted in remarkable irregularities of eye speed. These irregularities appeared in the form of spikes on electronystagmograms at the time constant of 0.03 sec. We measured the height of the spike by taking 40°/sec as a unit, and summed up the units of spikes appearing for 9 seconds to obtain the total index. The total indices ranged from zero (normal) to the forties (markedly abnormal). These numerals showed the level of abnormality of the eye tracking pattern more accurately than visual analysis, the method of determination in current use.
