UNLABELLED Exposure to noise has a harmful effect on the auditory health of workers. AIM The main goal of this paper was to establish the role of pure-tone audiometry and evoked transient otoacoustic emissions in the detection of small temporary auditory changes after exposure to high sound pressure levels. STUDY DESIGN A cross-sectional cohort study. MATERIAL AND METHODS 30 otologically ...

Otoacoustic emissions were evoked in the same ears with single tone bursts at 1, 2 and 3 kHz and with a complex stimulus consisting of a digital addition of the three tone bursts. Stimuli were presented at 75, 59 and 37 dB SPL to 28 ears of human subjects with normal hearing. The purpose was to determine if comparisons of responses to the complex stimulus with a posthoc addition of responses fr...

INTRODUCTION Noise is one of the harmful agents to health that is present in the various branches of economic activity. Hearing loss and tinnitus are among the most frequently reported complaints by workers exposed to occupational noise. OBJECTIVE To analyze the hearing and tinnitus in normal-hearing workers exposed to occupational noise. METHODS This is a cross-sectional analytical trial i...

Activation of the medial olivocochlear (MOC) efferents attenuates cochlear gain and reduces the amplitudes of mechanical, electrical, and neural cochlear outputs. The functional roles of the MOC efferents are not fully understood, especially in humans, despite postulations that they are involved in protection against acoustic trauma, facilitation of transient-sound perception, etc. Delineating ...

This study measured distortion product otoacoustic emissions (DPOAEs) and DPOAE input/output (I/O) curves to assess the effects of smoking on cochlear function. Twenty-four healthy adults, 12 smokers and 12 nonsmokers in the 20-30 years age range were selected based on self-reported histories of five to eight years of smoking or no smoking, respectively. All subjects received tympanometric scre...

In transmission-line models of cochlear mechanics, predictions about otoacoustic-emission delays depend on the place- or wave-fixed nature of the emission generation mechanism. In this work, transient evoked otoacoustic emissions (TEOAEs), recorded at different stimulus levels in 10 young subjects, were analyzed using wavelet-based time-frequency analysis to determine the latency of each freque...

UNLABELLED A pon stimulation by contralateral, ipsilateral or bilateral noise, the medial olivocochlear efferent tract changes the amplitude of otoacoustic emissions relative to the tested ear, reducing or removing it; this resulted in a reduction/suppression effect of otoacoustic emissions. Differences in patterns of elimination/reduction of otoacoustic emissions between ears have been documen...

We develop an objective, noninvasive method for determining the frequency selectivity of cochlear tuning at low and moderate sound levels. Applicable in humans at frequencies of 1 kHz and above, the method is based on the measurement of stimulus-frequency otoacoustic emissions and, unlike previous noninvasive physiological methods, does not depend on the frequency selectivity of masking or supp...

We characterized the 2F1-F2 distortion product reflected in the human frequency-following response (FFR). In the first experiment, we evaluated the input-output growth functions of the distortion product at 2F1-F2 (FFR-DP) for three primary pairs. In the second experiment, we tested the effect of primary tone level variation on the FFR-DP. The results for all three stimulus pairs showed that wh...

Distortion-product otoacoustic emissions (DPOAEs) in tympanal organs of insects are vulnerable to manipulations that interfere with the animal's physiological state. Starting at a medium temperature, we raised and lowered the locust's body temperature within the range of 12 to 35°C by changing the temperature of the surrounding air, while recording DPOAEs. These experimental manipulations resul...