The purpose of the present investigation was to define for young, middle-aged, and older adults the optimal frequency (cies) to record both the cervical vestibular-evoked myogenic potential (cVEMP) and the ocular vestibular-evoked myogenic potential (oVEMP). Further, this study aimed to describe age-related changes in the tuning of these two vestibular-evoked myogenic potentials.
This was a prospective study. Participants were 39 healthy adults (mean age 46.3 ± 15.7 years; range = 22 to 78 years; 15 men) equally divided into 3 age groups of 13 participants each: young adult (18 to 39 years), middle age (40 to 59 years), and old adult (≥60 years). cVEMPs and oVEMPs were recorded using air-conduction tone bursts at stimulus frequencies of 125, 250, 500, 750, 1000, 1500, and 2000 Hz presented at 127 dB pSPL.
There was a significant main effect of age group and frequency on the amplitude of both the cVEMP and the oVEMP. Amplitudes were largest for the Young adult group for the cVEMP and for the young adult and Middle age group for the oVEMP. The largest average peak-to-peak amplitude occurred in response to a 750 Hz tone burst for both responses. No significant differences in mean amplitude of the cVEMP or oVEMP were observed for 500, 750, or 1000 Hz stimuli. There was a significant interaction of age group and frequency for the cVEMP, suggesting a loss of tuning for the old adult group. Compared with the young adult group, the tuning of the cVEMP and oVEMP for the older adjults appeared to shift to a higher frequency.
There is no sharp tuning in the saccule and utricle. Instead, there is a range of best frequencies that may be used to evoke the cVEMP and oVEMP responses. The results of the present investigation also demonstrate that the optimal stimulus frequency to elicit a VEMP may change with age. Accordingly, 500 Hz may not be the ideal frequency to elicit VEMPs for all age groups. For this reason, in cases where the VEMP response is absent at 500 Hz it is recommended that attempts be made to record the VEMP for tone-burst frequencies of 750 or 1000 Hz.
The purpose of this investigation was to define the best frequency, or frequencies, to record the cervical vestibular-evoked myogenic potential (cVEMP) and ocular (VEMP) and to describe age-related changes in VEMP tuning. Subjects demonstrated a range of best frequencies. Compared with younger subjects, older subjects demonstrated a shift to higher best frequencies. Accordingly, 500 Hz may not be the ideal frequency to elicit VEMPs for all age groups. For this reason in cases where the VEMP response is absent at 500 Hz the authors recommend that attempts be made to record the VEMP for tone-burst frequencies of 750 or 1000 Hz.
1Division of Otolaryngology-Head and Neck Surgery, Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA; 2Division of Vestibular Sciences, Department of Hearing and Speech, Sciences, Vanderbilt University Medical Center, Nashville, Tennessee, USA; and 3Department of Rehabilitation Science, University of Buffalo, Buffalo, New York, USA.
ACKNOWLEDGMENTS: This investigation was supported in part by the Vanderbilt Clinical and Translational Science Award grant UL1 RR024975-01 from National Center for Research Resources/National Institutes of Health.
This investigation was submitted in partial fulfillment of the requirements for a Ph.D. in Hearing and Speech Sciences at Vanderbilt University.
Authors G. J. and D. M. are consultants for Interacoustics. The remaining authors declare no conflicts of interest.
Address for correspondence: Erin G. Piker, Duke University Medical Center, Box 3805, Durham, NC 27710, USA. E-mail: firstname.lastname@example.org