Multifrequency Narrowband Chirp Evoked Cervical Vestibular Myogenic Potentials: Evaluation of Responses in Normal-Hearing Young Adults

Abstract

Purpose: The study aimed to explore the various parameters of multifrequency narrowband Claus Elberling chirp (NB CE-chirp) evoked cervical vestibular evoked myogenic potentials (cVEMPs) in normal-hearing healthy young adults. The study also attempted to define the optimal frequency tuning characteristic of NB CE-chirp evoked cVEMPs. Method: cVEMP was performed on 26 young healthy adults using four different NB CE-chirps centered at 500, 1000, 2000, and 4000 Hz. The neck torsion method was applied for electrode placement. To have the acute recording, visual feedback of sternocleidomastoid muscle contraction was provided, and electromyography (EMG) scaling was done. Results: cVEMPs were present for 100% across all frequencies except at 4000 Hz. Amplitudes between each pair of frequencies were significantly different for EMG scaled and unscaled conditions. Frequency tuning was observed at 500 Hz regardless of scaling done. Positive peak 1 of cVEMP (P1) latencies showed no differences between frequencies while both negative peak 1 of cVEMP and the complex of positive peak 1 and negative peak 1 of cVEMP (P1N1) interpeak latency values decreased with increasing frequency. Interaural amplitude asymmetry ratio showed no difference between scaled and unscaled amplitudes. Intraclass correlation revealed a range of test–retest reliability across frequencies. EMG unscaled amplitude were having relatively lower test–retest reliability consistently across frequencies Conclusions: Differences in amplitudes between frequencies with a maximum at 500 Hz can be attributed to the low frequency centered saccular response. No differences in P1 were observed. Yet, N1 latency and P1N1 interpeak latency difference gradually shortened with the decrement in the stimulus duration as the stimulation frequency increased. The lower reliability of EMG unscaled amplitude across frequencies supports the need to use EMG scaling to avoid confounding variables related to muscle contraction.

Comparison of Multifrequency Narrow-Band CE-Chirp and Tone Burst Evoked Cervical Vestibular Evoked Myogenic Potentials

“…Although earlier studies have compared P1N1 amplitudes of the cVEMPs across single or two frequencies, 8,14,15 the present study is the initial one to compare cVEMPs over four octaves as often suggested in the literature. 16,17,18 Though the findings of the present study were consistent with the study by Özgür et al 26 and Ocal et al 8 it rejected the claim by some other studies. 14,15,24 Wang et al 24 published the first report of CE-chirp eliciting a significantly greater amplitude than 500 Hz tone bursts.…”

“…12,13 In meantime, these chirp stimuli have been effective in eliciting VEMP responses as well. 8,14,15,16 In the study by Ocal et al 8 NB CE-chirps and tone bursts at 500Hz were found to elicit no significant variations in P1N1 amplitude, however, the latency was significantly shortened with NB CE-chirp. On contrary, Reddy et al 15 revealed significantly larger cVEMP amplitude responses for 500 Hz NB CE-chirps than broadband chirps, clicks, and 500Hz tone bursts.…”

“…14 However, a greater number of frequency-centered stimuli has often been suggested in the literature to compare and define the tuning of VEMP responses. 16,17,18 Furthermore, a broader age range of participants might have had a negative effect on the results of the study 14 as it is well-established that aging results in declined response rates and amplitudes of VEMPs. 17,19 Thus, the need for comparing multi-frequency tone bursts and NB CE-chirps evoked cVEMP responses in the homogenous age group is evident.…”

Exploring the Relationship between Masseter and Cervical Vestibular-Evoked Myogenic Potentials in Young Adults with Hearing Thresholds Less Than or Equal to 15 dB HL

“…and cVEMPs (Lodha & Neupane 20 ; Sandhu et al 25 ) elicited using 500 Hz tone bursts. The responses of the otolith organs are known to exhibit greater prominence at lower mechanical resonance frequencies, which may explain present reflexes for all participants (Sandhu et al 25 ;…”

“…The electrode montage for cVEMP involved placing an inverting electrode at the sternocleidomastoid muscle, i.e., one-third region of the muscle, a non-inverting electrode at the sternoclavicular junction, and a common ground electrode on the lower forehead as given in Fig. 1 (Lodha & Neupane 20 ). Cervical VEMP was elicited using a 500Hz tone burst with a rise/fall and plateau time of one millisecond.…”