Suppressibility of the 2 f1- f2 stimulated acoustic emissions in gerbil and man

doi:10.1016/0378-5955(84)90092-3

Hearing Research

Volume 13, Issue 1, January 1984, Pages 29-37

https://doi.org/10.1016/0378-5955(84)90092-3 Get rights and content

Abstract

The suppression tuning properties of the oto-acoustic distortion product emission, 2f₁- f₂ have been measured in the ear canal of gerbil and man. The results show the acoustic response to be suppressible in a similar, frequency-dependent manner in both species. Frequencies near to those of the stimulating tones are most effective in suppressing the response. Derived iso-suppression tuning curves have Q_10dB values of between 1 and 6. Suppressor tones having frequencies near to f₂ (the higher frequency stimulus) make a contribution to the tuning curve which is largely independent of the stimulus intensity and the frequency ratio between the two primary tones. Suppressors having f₁-associated frequencies produce a variable amount of suppression depending on the stimulus parameters chosen. No specific suppression feature could be associated with suppressors near to 2f₁- f₂.

The frequency selectivity of the acoustic DP generation mechanism shown by this study indicates a close association with the transduction mechanism. The demonstration of comparable signals in gerbil and man facilitates the direct transfer of laboratory results to the study of human ears.

References (19)

M.A. Cheatham et al.
Two tone interactions in the cochlear microphonic
Hearing Res.
(1982)
D.T. Kemp
Towards a model for the origin of cochlear echoes
Hearing Res.
(1980)
D.T. Kemp et al.
Ear canal acoustic and round window electrical correlates of 2f₁-f₂ generation in the cochlea
Hearing Res.
(1984)
P.M. Sellick et al.
Two tone suppression in cochlear hair cells
Hearing Res.
(1979)
E. Zwicker et al.
Acoustical responses and suppression period patterns in guinea pigs
Hearing Res.
(1981)
A.M. Brown et al.
Oto-acoustic emissions: the suppression tuning properties of the distortion product 2f₁-f₂ in gerbil and man
Br. J. Audiol.
(1983)
G.L. Gibian et al.
Cochlear microphonic evidence for mechanical propagation of distortion products (f₂ -f₁) and (2f₁-f₂)
Hearing Res.
(1983)
D.T. Kemp
Stimulated acoustic emissions from within the human auditory system
J. Acoust. Soc. Am.
(1978)
D.T. Kemp
Evidence of nonlinearity and frequency selective wave amplification in the cochlea
Arch. Oto-Rhino-Laryngol.
(1979)

There are more references available in the full text version of this article.

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The DPOAE levels are typically noted with respect to the primary-tone frequencies rather than the DPOAE frequency. This standard representation is because research indicates that the 2f1-f2 DPOAE is generated in the basilar membrane region of the cochlea that maximally responds to the primary tones, i.e., at the place where the two tones optimally overlap (Brown and Kemp, 1984; Martin et al., 1987). Thus, DPOAEs best reflect the status of OHC function in this frequency region, and the reference frequency commonly used is that of f2.
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One could ask why it is possible to model the behaviour of low-frequency biased DPOAEs with one single, saturating non-linearity. After all, aside from the generation of DPOAEs at the characteristic frequency place of f2, where the excitations evoked by the primary tones overlap based on a MET transfer function (Brown and Kemp, 1984; Martin et al., 1987), the cochlea has numerous potential sources of non-linearity in both mechanisms and locations. A recent study by Verpy et al. (2008) showed that non-linear properties of the cochlea are absent in stereocilin-null mutant mice lacking horizontal top connectors of outer hair cells.
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Here, we compare the properties of low-frequency (30 Hz, 80–120 dB SPL) modulated CDPOAE and QDPOAEs evoked with f₂ = 2 and 5 kHz in human subjects with normal hearing. The modulation depth was quantified with the modulation index (MI), a measure which considers both amplitude and phase.
Modulated CDPOAEs evoked with f₂ = 2 kHz have amplitude maxima at the zero crossings and amplitude minima at the extremes of the biasing tone (BT) which correlate positively with the BT level. CDPOAEs evoked with f₂ = 5 kHz were recorded during biasing in exactly the same way as described before. At the highest BT levels used (120 dB SPL), very little modulation could be detected. Not only the depth, but also the shape of the QDPOAE modulation pattern is correlated with the BT level. At moderate BT levels (about 90–100 dB SPL) QDPOAEs evoked with f₂ = 5 kHz show one amplitude notch around the zero crossing of the positive going flank of the BT (a single modulation pattern). At and above a BT level of about 105 dB SPL, the pattern reverses and shows a double modulation pattern. At the highest BT level used (120 dB SPL), quadratic MIs exceed cubic MIs (2.0 ± 0.5 and 0.97 ± 0.06, respectively).
Patterns of low-frequency modulated QDPOAEs in humans are similar to the modulation seen in animal studies and as predicted by mathematical models. Human low-frequency modulated QDPOAEs are ideally suited to estimate cochlear OP shifts because of their high sensitivity to the OP shift.
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EOAEs are emissions elicited by sound stimuli, and encompass transient evoked OAEs (TEOAEs), stimulus frequency OAEs, and distortion product OAEs (DPOAEs). DPOAEs were first reported by Brown and Kemp [4], and are particularly beneficial in auditory research and in clinical use because of their frequency specificity, broad bandwidth, and wider dynamic range compared to other OAEs [5]. DPOAEs are now widely accepted as a non-invasive tool for the objective screening of hearing loss; however, there have been only a few reports on the predictive value of DPOAEs in the hearing prognosis of ISSNHL.
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Seventy-eight consecutive patients with ISSNHL were enrolled. DPOAEs were measured at the first hospital visit. Two primary pure tones with a frequency ratio (f2/f1) of 1.2 were used at non-equal sound pressure levels (L1/L2 = 80/70 dB SPL). The DPOAE amplitude was measured at the 11 frequencies of 2f1–f2 with f2 varying from 593 to 6031 Hz. All the patients received steroid administration in combination with hyperbaric oxygen (HBO) therapy. Hearing recovery was evaluated by the improvement in hearing compared to the unaffected contralateral ear. Correlations between the hearing improvement rate and five potential prognostic factors (the DPOAE amplitude, patient's age, days from onset to the start of treatment, initial hearing level, and presence of vertigo) were examined by simple and multiple regression analyses.
The net DPOAE amplitude in patients with hearing improvement rate ≥50% was significantly larger than that with hearing improvement rate <50% at f2 frequencies of 3031 and 4812 Hz (unpaired Student's t-test, p < 0.05). A simple regression analysis showed that the hearing improvement rate significantly correlated with the net DPOAE amplitude at f2 frequencies of 3031 and 4812 Hz, but not with that at the other f2 frequencies tested. The correlation coefficients were 0.528 and 0.522 for 3031 and 4812 Hz, respectively, with p values <1 × 10⁻⁶. In a multiple regression analysis, the partial correlation coefficients of the net DPOAE amplitude were 0.308 and 0.246 with p values of 0.008 and 0.036 for 3031 and 4812 Hz, respectively.
The significant correlation between hearing recovery and DPOAEs measured before treatment indicates that DPOAEs are a potentially useful means of predicting hearing prognosis in ISSNHL.
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Suppressibility of the 2 f1- f2 stimulated acoustic emissions in gerbil and man

Abstract

Hearing Res.

Hearing Res.

Hearing Res.

Hearing Res.

Hearing Res.

Oto-acoustic emissions: the suppression tuning properties of the distortion product 2f1-f2 in gerbil and man

Br. J. Audiol.

Cochlear microphonic evidence for mechanical propagation of distortion products (f2 -f1) and (2f1-f2)

Hearing Res.

Stimulated acoustic emissions from within the human auditory system

J. Acoust. Soc. Am.

Evidence of nonlinearity and frequency selective wave amplification in the cochlea

Arch. Oto-Rhino-Laryngol.

Suppressibility of the 2 f₁- f₂ stimulated acoustic emissions in gerbil and man

Oto-acoustic emissions: the suppression tuning properties of the distortion product 2f₁-f₂ in gerbil and man

Cochlear microphonic evidence for mechanical propagation of distortion products (f₂ -f₁) and (2f₁-f₂)