Effects of increased stimulus rate on brainstem electric response (BER) audiometry as a function of age.

The purpose of this investigation was to describe the effects of rate of stimulus presentation on the brainstem electric response in groups selected as models for such brainstem disorders as demyelinating diseases and focal lesions. Two groups, infants and geriatric adults, were chosen as models because of their known neurological differences from a normal young adult population. Three groups of eight subjects each; infants, geriatric adults, and young adults were tested using routine brainstem electric response techniques with four rates of click presentations. Using the wave V latency at the slow rate (13/sec) as base line, three latency shift scores were obtained for each of the three fast rates (33/sec), 50/sec, 67/sec). Analysis of the data revealed greater shifts for infants and geriatric adults than were present for the young adults. The experimenters concluded that the imposition of a fast rate of click presentation offers a promise as a clinical tool for the discovery of brainstem differences.