Olivocochlear Activity and Temporary Threshold Shift‐Susceptibility in Humans

Wagner, Wolfgang; Heppelmann, Guido; Kuehn, M; Tisch, M.; Vonthein, Reinhard; Zenner, Hans‐Peter

doi:10.1097/01.mlg.0000181463.16591.a7

Cited by 30 publications

(26 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Wagner et al (2008) calculated MOC efferent activity as (a) the mean of level changes (negative and positive values combined) for each subject upon contralateral stimulation, (b) the mean of all level changes in absolute value irrespective of whether the MOC effect was a reduction or enhancement of OAE amplitude, and (c) the difference between the highest and lowest suppression value (range of suppression) for each subject. Their results suggest good repeatability for the two DPOAE protocols, with the exception of range of suppression in protocol A, and were consistent with their previous studies using similar methods (Wagner et al, 2005;Wagner, Heppelmann, Müller, Janssen, & Zenner, 2007). Wagner et al's (2008) estimation of the MOC reflex, however, was compromised for at least two reasons.…”

supporting

confidence: 78%

“…Present results cannot be directly compared with previous studies that used DPOAEs without controlling for fine structure (Kumar et al, 2013;Wagner et al, 2005Wagner et al, , 2007Wagner et al, , 2008. Using click-evoked OAEs, de Boer and Thornton (2008) reported a mean increase in the MOC reflex of 0.63 dB on Day 4 and 0.78 dB on Day 5 when they implemented a 5-day training regimen to improve listening in adults with normal hearing.…”

Section: Comparison With Literaturecontrasting

confidence: 52%

See 1 more Smart Citation

Stability of the Medial Olivocochlear Reflex as Measured by Distortion Product Otoacoustic Emissions

Mishra

Abdala

2015

J Speech Lang Hear Res

View full text Add to dashboard Cite

Purpose: The purpose of this study was to assess the repeatability of a fine-resolution, distortion product otoacoustic emission (DPOAE)-based assay of the medial olivocochlear (MOC) reflex in normal-hearing adults. Method: Data were collected during 36 test sessions from 4 normal-hearing adults to assess short-term stability and 5 normal-hearing adults to assess long-term stability. DPOAE level and phase measurements were recorded with and without contralateral acoustic stimulation. MOC reflex indices were computed by (a) noting contralateral acoustic stimulation-induced changes in DPOAE level (both absolute and normalized) at fine-structure peaks, (b) recording the effect as a vector difference, and (c) separating DPOAE components and considering a component-specific metric.Results: Analyses indicated good repeatability of all indices of the MOC reflex in most frequency ranges. Short-and long-term repeatability were generally comparable. Indices normalized to a subject's own baseline fared best, showing strong short-and long-term stability across all frequency intervals. Conclusions: These results suggest that fine-resolution DPOAE-based measures of the MOC reflex measured at strategic frequencies are stable, and natural variance from day-to-day or week-to-week durations is small enough to detect between-group differences and possibly to monitor intervention-related success. However, this is an empirical question that must be directly tested to confirm its utility.

show abstract

supporting

confidence: 78%

Section: Comparison With Literaturecontrasting

confidence: 52%

Stability of the Medial Olivocochlear Reflex as Measured by Distortion Product Otoacoustic Emissions

Mishra

Abdala

2015

J Speech Lang Hear Res

View full text Add to dashboard Cite

show abstract

“…There are also several other papers that show individual MOCR effects across subjects from which MOCR strength distributions might be calculated (Micheyl et al 1995;Micheyl and Collet 1996;Kumar and Vanaja 2004;Muller et al 2005;Wagner et al 2005Wagner et al , 2007. A major drawback of the De Ceulaer et al distribution is that no information was provided on the amount of measurement error in the data.…”

Section: Comparison With Prior Workmentioning

confidence: 99%

“…Although there are considerable data showing that there is a medial olivocochlear reflex (MOCR) in humans, most studies show averages and only a few show MOCR effects across individual subjects (Micheyl et al 1995;Micheyl and Collet 1996;De Ceulaer et al 2001;Wagner et al 2005). De Ceulaer et al (2001) presented the first measured distribution of MOCR strengths across individuals using otoacoustic emissions (OAEs).…”

Section: Introductionmentioning

confidence: 99%

Measurement of the Distribution of Medial Olivocochlear Acoustic Reflex Strengths Across Normal-Hearing Individuals via Otoacoustic Emissions

Backus

Guinan

2007

JARO

View full text Add to dashboard Cite

A clinical test for the strength of the medial olivocochlear reflex (MOCR) might be valuable as a predictor of individuals at risk for acoustic trauma or for explaining why some people have trouble understanding speech in noise. A first step in developing a clinical test for MOCR strength is to determine the range and variation of MOCR strength in a research setting. A measure of MOCR strength near 1 kHz was made across a normalhearing population (N=25) by monitoring stimulusfrequency otoacoustic emissions (SFOAEs) while activating the MOCR with 60 dB SPL wideband contralateral noise. Statistically significant MOCR effects were measured in all 25 subjects; but not all SFOAE frequencies tested produced significant effects within the time allotted. To get a metric of MOCR strength, MOCR-induced changes in SFOAEs were normalized by the SFOAE amplitude obtained by two-tone suppression. We found this Bnormalized MOCR effect^varied across frequency and time within the same subject, sometimes with significant differences between measurements made as little as 40 Hz apart or as little as a few minutes apart. Averaging several single-frequency measures spanning 200 Hz in each subject reduced the frequency-and time-dependent variations enough to produce correlated measures indicative of the true MOCR strength near 1 kHz for each subject. The distribution of MOCR strengths, in terms of SFOAE suppression near 1 kHz, across our normal-hearing subject pool was reasonably approximated by a normal distribution with mean suppression of approximately 35% and standard deviation of approximately 12%. The range of MOCR strengths spanned a factor of 4, suggesting that whatever function the MOCR plays in hearing (e.g., enhancing signal detection in noise, reducing acoustic trauma), different people will have corresponding differences in their abilities to perform that function.

show abstract

“…Since 1930, a considerable number of studies were unsuccessful in reaching that goal. Among the audiological methods used were discrimination of loudness, temporal sound integration ability, speech discrimination in background noise, and stapedial reflex (SR) measurement [overview in Wagner et al, 2005]. A breakthrough in our understanding of individual noise vulnerability emerged in the 1980s when studies demonstrated in different mammal species that the neural activity of the medial olivocochlear efferents (MOC) can exert a noise-protective role on the cochlea [Rajan and Johnstone, 1983].…”

Section: Introductionmentioning

confidence: 99%

Assessment of the Noise-Protective Action of the Olivocochlear Efferents in Humans

Wolpert

Heyd²,

Wagner³

2013

Audiol Neurotol

View full text Add to dashboard Cite

It has been demonstrated in different mammals that the medial olivocochlear efferents (MOC) exert a noise-protective effect on the cochlea. In humans such an effect has not unambiguously been shown as of yet. The objective of this study was to assess the relationship between MOC activity and susceptibility of the cochlea to noise-induced hearing loss in humans. In 40 normally hearing human subjects, we measured the following: (1) magnitude of temporary threshold shift (TTS) after exposure to 60 min broadband noise of 94 dB SPL and (2) contralateral suppression (CS) of distortion product otoacoustic emissions (which reflects MOC activity) using two different measurement paradigms. CS was measured in duplicate on 2 measurement days. The relationship between TTS and CS was assessed. Individual TTS in the most affected frequencies (4 > 3 > 8 kHz) ranged from 9 to 28 dB HL, with an average maximum TTS of 18.4 dB HL. The amount of CS ranged between 0.3 and 3 dB. The repeatability of CS, evaluated by Cronbach's α value, ranged from 0.76 (acceptable repeatability) to 0.86 (good repeatability). One of the two different measurement paradigms showed a statistically significant inverse correlation between CS magnitude and amount of TTS, which was hypothesized. This is the first study on the relationship between TTS and CS in humans employing TTS induced under controlled laboratory conditions and two different MOC paradigms. The findings are compatible with the hypothesis that MOC activity is noise protective in humans. Future perspectives include modified CS paradigms, longitudinal cohort studies or efforts to also monitor lateral efferent effects in humans.

show abstract

Olivocochlear Activity and Temporary Threshold Shift‐Susceptibility in Humans

Cited by 30 publications

References 29 publications

Stability of the Medial Olivocochlear Reflex as Measured by Distortion Product Otoacoustic Emissions

Stability of the Medial Olivocochlear Reflex as Measured by Distortion Product Otoacoustic Emissions

Measurement of the Distribution of Medial Olivocochlear Acoustic Reflex Strengths Across Normal-Hearing Individuals via Otoacoustic Emissions

Assessment of the Noise-Protective Action of the Olivocochlear Efferents in Humans

Contact Info

Product

Resources

About