Types of Objective Electrical Vestibulograms

Abstract

Objective electrical vestibulograms, which are plots of objectively determined absolute thresholds against stimulus frequency for a lateral swaying response in standing, blindfolded Ss to sinusoidal electrical stimuli of various frequencies passed between Ss' mastoid processes, were determined for 32 Ss, 19 in the present experiment, and a total of 13 from two earlier experiments. The vestibulograms of individual Ss could be visually separated into six types, with four of them accounting for 28 or 87.5% of the 32 Ss. The shapes of the first four types were supported by the results of a factor analysis. The visual separation criteria were individual vestibulograms having: (1) a maximum at 4.0 cps, (2) peaks at 0.50 and 4.0 cps, (3) peaks at 0.50 and 2.0 cps, (4) a maximum at 1.0 cps, (5) a maximum at 0.20 cps, and (6) a maximum at 2.0 cps. A test showed that these six types were not related to differences in modes of swaying of Ss in response to the different stimulus frequencies.