Multifrequency Narrowband Chirp Evoked Masseter Vestibular-Evoked Myogenic Potential in Healthy Young Adults

Abstract

The masseter vestibular evoked myogenic potential (mVEMP) is a relatively new assessment tool utilized to examine the vestibulo-masseteric reflex. Recently, studies have been increasing to understand the significance of mVEMP better. However, there is still little information available on the normative of mVEMP. The study aimed to characterize the latency of p11 and n21 peaks, and the amplitude of the p11-n21 peak complex of narrow band chirp evoked masseter VEMP in healthy young adults. The study involved a group of 30 individuals whose ages ranged between 18 and 30 years. Each participant underwent masseter VEMP testing using narrowband chirp stimuli of 500, 1000, 2000, and 4000 Hz at 125 dB SPL. The results showed that the response rate was higher for 500 and 1000 Hz with a 100% response rate, whereas the response rate was reduced for 2000 Hz (95%) and 4000 Hz (80%) narrow band chirp stimuli. There were significant differences in the p11 and n21 latencies of the responses across frequencies. The latency of the p11 and the n21 peaks were shortest for the 500 Hz stimulus, followed by the 1000 Hz, 2000 Hz and 4000 Hz stimuli. This indicates that as the frequency of the stimulus increases, the latency of the response also increases. The amplitude measures of the p11-n21 peak complex showed significant differences across frequencies except between the 500 and 1000 Hz responses. The 500 Hz response had the largest amplitude, followed by the 1000 Hz, 2000 Hz and 4000 Hz. This indicates that as the frequency of the stimulus increases, the amplitude of the p11-n21 peak complex decreases. This study suggests that when narrowband chirp stimuli of different frequencies, such as 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz are used, different normative should be used for analyzing the response of each frequency. The study's results indicate that 500 Hz and 1000 Hz chirps are the best stimuli for recoding mVEMP.