The Vestibular-Auditory Interaction for Auditory Brainstem Response to Low Frequencies

Abstract

Since saccular projection is sound sensitive, the objective is to investigate the possibility that the saccular projections may contribute to auditory brainstem response to 500 HZ tone burst (ABR500 HZ). During the case-control research, twenty healthy controls compared to forty selected case groups as having chronic and resistant BPPV were evaluated in the audiology department of Hamadan University of Medical Sciences (Hamadan, Iran). Assessment is comprised of audiologic examinations, cervical vestibular evoked myogenic potentials (cVEMPs), and ABR500 HZ. We found that forty affected ears of BPPV patients with decreased vestibular excitability as detected by abnormal cVEMPs had abnormal results in ABR500 HZ, whereas unaffected ears presented normal findings. Multiple comparisons of mean p13, n23 latencies, and peak-to-peak amplitudes between three groups (affected, unaffected, and healthy ears) were significant. In conclusion, the saccular nerves can be projective to auditory bundles and interact with auditory brainstem response to low frequencies. Combine the cVEMPs and ABR500 HZ in battery approach tests of vestibular assessment and produce valuable data for judgment on the site of lesion. Regarding vestibular cooperation for making of wave V, it is reasonable that the term of ABR500 HZ is not adequate and the new term or vestibular-auditory brainstem response to 500 HZ tone burst is more suitable.

Central Representation of Cervical Vestibular Evoked Myogenic Potentials

“…There is a significant relationship between abnormal findings of cVEMPs and abnormal findings of slow wave ABR component (decreased neural synchronization) [ 30 ] 11 Butler and Trainor [ 31 ]: There is the strong cooperation between the auditory and vestibulo-motor systems for rhythm perception and neural synchronization [ 31 ] 12 Kassow et al [ 32 ]: The SVSS contribute in acoustico-motor synchronization. The P300 wave of the evoked electrophysiological responses amplifies during non-self-voice practice and synchronised motion [ 32 ] 13 Emami and Gohary [ 33 ]: The saccular nerves fibers can be projective to auditory bundles and interact with auditory brainstem response to 500 HZ tone. There is a relationship between normal results of the cVEMPs and the amplitude wave-V ABR 500 HZ.…”

“…There is a relationship between normal results of the cVEMPs and the amplitude wave-V ABR 500 HZ. It is also obvious that the word of ABR 500 HZ is not suitable and the novel term or vestibular-auditory brainstem response to 500 HZ tone burst is more possible [ 33 ] 14 Trivelli et al [ 34 ]: The cVEMPs is obtainable in deaf people and the saccule has sound sensitivity for intense low frequencies [ 34 ] 15 Emami [ 35 ]: Auditory training and more experience of self-voice production improved neural synchronization in auditory nerve fibers, and also can increased cVEMPs amplitude in deaf people [ 35 ] 16 Emami [ 36 ]: In high-level of noisy competing situations, healthy human saccular sensation can mediate the detection of low frequencies [ 36 ] 17 Emami et al [ 37 ]: The score of phonemes recognition in white noise is higher in persons with normal cVEMPs [ 37 ] 18 Iannotti et al [ 38 ]: The highest score of speech discrimination at most comfortable level of hearing is related to the bone-conducted human voice, and causes better neural processing in the insula, cingulate cortex, and medial temporal lobe. Indeed, human hearing is multi modal [ 38 ] 19 Emami et al [ 39 ]: The people with normal cVEMPs had better word recognition scores in white noise [ 39 ] 20 Longridge et al [ 13 ]: Internal sounds are decreased by stapedius reflex, when they reach to the ear through the air and bone-conducted pathway.…”

“…The brainstem encodes the first formant of speech (the lowest frequency or the strongest harmonic of the speaker's voice), which is necessary for the perception of vowels [ 51 , 54 ]. Therefore, the acoustical information of the vestibular system that goes to the brainstem may be effective in detection beats and pitch [ 30 , 33 ].…”

Saccular Dysfunction in Low-Frequency Age-Related Sensorineural Hearing Loss

“…They reported conservational sounds (voice pitch in speaking, singing, crowd actions, vocalisations and musicalnoises) can stimulate the saccule [13]. The recent articles show that acoustical activation of the saccule in human enhanced temporal fine arrangement signals of the sound and has very important starring role in recognition of harmonic pitch data to separate the message and maskers, which are essential for audible function in noise [14]. The latest reports discuss about a novel finding, which confirms saccular projection activations make the cues in human brainstem to cortex and can possibly contribute to auditory processing [13][14][15][16].…”

“…Previous studies have focused on the possibility that saccule has auditory sensitivity in human and in the clamor environments may contribute to the hearing of low frequency high-intensity sounds. Indeed, the saccule has a compensatory role for the hearing of aloud low frequencies (90 dB spl<) and allows to phonemic selfregulation [12][13][14][15][16]. More probability of this sacculocochlear comorbidity in elderly is that reduced output from the impaired sensory systems, due in part to a-SNHL changes, decreases the value of the input to the central auditory-vestibular system and eventually the communication challenges concomitant with age related hearing loss [9], it may well be that impaired hearing statuses more necessity on consideration sharing, thus, making mobility further of a challenge.…”