Changes in the vestibulo-ocular reflex: a study of elderly day hospital patients

The vestibulo-ocular reflex (VOR) of 50 elderly day hospital patients (mean age of 82 years) was studied with the head autorotation test. Amplitude gain, phase and the highest frequency band reached were determined in the five frequency bands of 1, 2, 3, 4, and 5 Hz. Of the 50 patients, 81% had abnormal results. The gain of the elderly was significantly increased to 1.06-1.24 in the frequency bands of 3, 4, and 5 Hz in comparison with that of a control group. The elderly showed constantly a phase lead of 8-19 degrees in the frequency range of 1-4 hz and in this range differed significantly from the control group. The percentage of the elderly who reached high frequencies of head movements was reduced to 55% in the frequency band of 3 Hz and to 30% in the frequency band of 4 Hz. These findings may lead to oscillopsia and explain the high prevalence of dizziness and falls among the elderly.