Sound Sensitivity of the Saccule for Low Frequencies in Healthy Adults

Abstract

Approximately 80 years ago John Tait speculated about a possible auditory role for the otolith organs in humans those days, there was no direct evidence for that idea. This time is for us to review and research. Then, the objective of our study was to investigate saccular hearing in healthy adults. We selected twenty healthy controls and twenty-four dizzy cases. Assessment comprised of audiologic evaluations, cervical vestibular evoked myogenic potentials (cVEMPs), and recognition of spoken phonemes in white noise (Rsp in wn). In the case group (a total of 48 ears), the cVEMPs abnormalities were all unilateral (24 affected ears and 24 contralateral unaffected ears). Affected ears with decreased vestibular excitability as detected by abnormal cVEMPs had decreased Rsp in wn (mean=60.78±8.33), whereas both unaffected (mean=96.24±2.4) and control ears (mean=96.24±2.4) presented normal results. The correlation between RSP in wn and p13 latencies was significant (P<0.05, r=-0.551). The peak-to-peak amplitudes showed significant correlation to RSP in wn (P<0.05, r=0.307). The correlation between RSP in wn and the latencies of n23 was significant (P<0.05, r=-0.493). We concluded in presence of severe competing noise, saccule has a facilitating role for cochlea and can improve to detection of loud low-frequencies.