INTRODUCTION Tinnitus is a perception of sound without external source. The exact etiology of tinnitus is not fully understood, although some researchers believe that the condition usually starts in the cochlea. The aim of this study was to determine the potential contribution of outer hair cell dysfunction to chronic tinnitus, by application of Distortion-Product Evoked Otoacoustic Emission (D...

OBJECTIVE A cisplatin ototoxicity monitoring protocol was recently proposed using distortion-product otoacoustic emissions (DPOAEs) measured in 1/48th octave steps over the highest obtainable quarter octave ( Dille et al, 2010 ). This protocol can take up to 40 minutes to complete in both ears among seriously ill patients in a potentially noisy test environment. The goal of the current study wa...

Distortion-product otoacoustic emissions (DPOAEs) arise in the cochlea in response to two tones with frequencies f1 and f2 and mainly consist of two components, a nonlinear-distortion and a coherent-reflection component. Wave interference between these components limits the accuracy of DPOAEs when evaluating the function of the cochlea with conventional continuous stimulus tones. Here, DPOAE co...

The medial olivocochlear reflex (MOCR) modulates cochlear amplifier gain and is thought to facilitate the detection of signals in noise. High-resolution distortion product otoacoustic emissions (DPOAEs) were recorded in teens, young, middle-aged, and elderly adults at moderate levels using primary tones swept from 0.5 to 4 kHz with and without a contralateral acoustic stimulus (CAS) to elicit m...

microscopy (SEM) and Distortion Product Otoacoustic Emission (DPOAE). Materials and Methods: In this study, eight adult albino guinea pigs were used as the study group (n = 4) and control group (n = 4). DPOAE measurements of both groups were performed before the procedure. 2 hours before administration of the noise, 0.9% NaCl solution was intraperitoneally injected to control group and vitamin ...

The present data were collected in humans to characterize the effects of monaural and binaural stimulation and contralateral noise on the 2f1-f2 distortion-product otoacoustic emission (DPOAE) adaptation response. DPOAE levels (f2/f1=1.21, L1=70 dB SPL, L2=65 dB SPL) were measured in both ears for a range of f2 frequencies (1.2 to 10.0 kHz). The f2 frequency producing the largest amplitude DPOA...

UNLABELLED BACKGROUND Whole body vibration (WBV) is a potentially harmful consequence resulting from the dissipation of energy by industrial machineries. The result of WBV exposure on the auditory system remains unknown. The objective of the present research was to evaluate the influence of WBV on cochlear function, in particular outer hair cell function. It is hypothesized that WBV impairs ...

The distortion product otoacoustic emission (DPOAE) fine structure is revealed, when measuring DPOAE with a very fine frequency resolution. It is characterized by consistent maxima and minima with notches of up to 20 dB depth. The fine structure is known also from absolute hearing thresholds, and has recently been demonstrated to exist in low level equal-loudness contours. The character of the ...

UNLABELLED Different studies have been carried out in order to correlate audiometric thresholds and distortion product otoacoustic emissions measurements (DPOAE). However, high variability and external interferences make hearing thresholds estimates by means of the DPOAE very little sensitive. The aim of this study was to check the correspondence between the pure tone thresholds and the cochlea...

BACKGROUND The aim of this study was to investigate the effects of sub-clinical alterations on the amplitudes and slopes of the DPOAE input-output responses from subjects with previous history of middle ear dysfunction. MATERIAL/METHODS The study included 15 subjects with and 15 subjects without a history of otitis media in the last 10 years. All participants were assessed with acoustic immit...