The objective of this cross-sectional study is to compare bone-conducted low-frequency hearing thresholds (BClf) to cervical vestibular evoked myogenic potentials (cVEMPs) findings in prelingual adult deaf patients. The fifty participants (100 ears) included twenty healthy controls and thirty other subjects selected from patients who presented with bilateral prelingual deafness to Department of Audiology of Hamadan University of Medical Sciences and Health Services (Hamadan, Iran). Assessments comprised of audiological evaluations, cVEMPs, and computerized tomography scans. Twenty deaf patients (forty affected ears) with bilateral decreased vestibular excitability as detected by abnormal cVEMPs revealed that BClf hearing thresholds were completely absent. Ten deaf patients (twenty unaffected ears) with normal cVEMPs reported a sensation of the sound at BClf hearing thresholds (the mean for and for ). Multiple comparisons of mean p 13 latencies, mean n23 latencies and peak-to-peak amplitudes between three groups were significant (P = 0.01 for all, one-way ANOVA test). Multiple Comparisons of mean BClf between three groups were significant (P = 0.00, One-way ANOVA test). Conclusion. Hypersensitivity of vestibular system to sound augments BClf hearing thresholds in deaf patients. The sensation of the sound at low frequencies may be present in patients with total deafness and normal vestibular function (predominantly saccule). This improvement disappears when saccular function is lost. 1. Introduction The mammalian inner ear contains sense organs responsible for detecting sound, gravity, and acceleration. Of these organs, the cochlea is involved in hearing, while the otolith organs (saccule and utricle) serve to detect linear acceleration [1]. Recent evidences from human show that the saccule has acoustic sensitivity to sound [2–4], which can contribute to the affective quality of loud low frequencies [4]. Saccular stimulation to air-conducted sound has a compensatory role for cochlear hearing in noisy conditions [3]. Saccule not only responds best to low frequency high-intensity air-conducted sound, but also, in clamor conditions, may contribute to the hearing of this frequency band [2]. Saccular hearing is an effective reinforcer for cochlear hearing [4]. It can cooperate to frequency and intensity discrimination [5, 6]. The otolith organs have a mechanical tuning due to their elastic and inertial properties and the band-width of their mechanical response extending to 500？Hz. The sensitivity of the human vestibular system to bone-conducted stimulation
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