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Acta Otorrinolaringologica Espanola 2015Given the relevance of possible hearing losses due to sound overloads and the short list of references of objective procedures for their study, we provide a technique...
INTRODUCTION AND OBJECTIVES
Given the relevance of possible hearing losses due to sound overloads and the short list of references of objective procedures for their study, we provide a technique that gives precise data about the audiometric profile and recruitment factor. Our objectives were to determine peripheral fatigue, through the cochlear microphonic response to sound pressure overload stimuli, as well as to measure recovery time, establishing parameters for differentiation with regard to current psychoacoustic and clinical studies.
MATERIAL AND METHOD
We used specific instruments for the study of cochlear microphonic response, plus a function generator that provided us with stimuli of different intensities and harmonic components. In Wistar rats, we first measured the normal microphonic response and then the effect of auditory fatigue on it.
RESULTS
Using a 60dB pure tone acoustic stimulation, we obtained a microphonic response at 20dB. We then caused fatigue with 100dB of the same frequency, reaching a loss of approximately 11dB after 15minutes; after that, the deterioration slowed and did not exceed 15dB. By means of complex random tone maskers or white noise, no fatigue was caused to the sensory receptors, not even at levels of 100dB and over an hour of overstimulation.
CONCLUSIONS
No fatigue was observed in terms of sensory receptors. Deterioration of peripheral perception through intense overstimulation may be due to biochemical changes of desensitisation due to exhaustion. Auditory fatigue in subjective clinical trials presumably affects supracochlear sections. The auditory fatigue tests found are not in line with those obtained subjectively in clinical and psychoacoustic trials.
Topics: Acoustic Stimulation; Animals; Audiometry, Pure-Tone; Auditory Fatigue; Cochlear Microphonic Potentials; Equipment Design; Hair Cells, Auditory, Outer; Noise; Rats; Rats, Wistar
PubMed: 25109540
DOI: 10.1016/j.otorri.2014.05.004 -
Hearing Research Apr 1985A model is introduced for auditory adaptation based on the stochastic models that are widely documented for birth and death processes and used as a vehicle to review... (Review)
Review
A model is introduced for auditory adaptation based on the stochastic models that are widely documented for birth and death processes and used as a vehicle to review single unit and compound action potential studies as well as various models for adaptation and forward masking. It appears that such a model inherently incorporates a relation between the perstimulatory adaptation time constant, the poststimulatory recovery time constant and the ratio between adapted firing rate and onset firing rate. The knowledge of any two of these parameters allows the prediction of the third one. The model takes into account postsynaptic membrane properties. The model based on Markov assumptions is a linear one. Although onset firing rates depend on a nonlinear way upon stimulus level, the above mentioned time constants and the adapted rate to onset rate ratio are intensity independent. The idea is put forward and tested that a comparable situation exists for the depression effects produced by mild auditory fatigue. The apparent findings that time constants tend to be intensity dependent for auditory fatigue is explained on basis of an interaction effect of dependent exponential processes.
Topics: Action Potentials; Adaptation, Physiological; Animals; Auditory Fatigue; Auditory Threshold; Goldfish; Guinea Pigs; Hair Cells, Auditory; Hearing; Mathematics; Membrane Potentials; Models, Neurological; Perceptual Masking; Stochastic Processes; Synapses; Synaptic Transmission; Vestibulocochlear Nerve
PubMed: 2993220
DOI: 10.1016/0378-5955(85)90110-8 -
The Journal of the Acoustical Society... Mar 2024Auditory brainstem responses (ABRs) were measured at 57 kHz in two dolphins warned of an impending intense tone at 40 kHz. Over the course of testing, the duration of...
Auditory brainstem responses (ABRs) were measured at 57 kHz in two dolphins warned of an impending intense tone at 40 kHz. Over the course of testing, the duration of the intense tone was increased from 0.5 to 16 s to determine if changes in ABRs observed after cessation of the intense sound were the result of post-stimulatory auditory fatigue or conditioned hearing attenuation. One dolphin exhibited conditioned hearing attenuation after the warning sound preceding the intense sound, but little evidence of post-stimulatory fatigue after the intense sound. The second dolphin showed no conditioned attenuation before the intense sound, but auditory fatigue afterwards. The fatigue was observed within a few seconds after cessation of the intense tone: i.e., at time scales much shorter than those in previous studies of marine mammal noise-induced threshold shifts, which feature measurements on the order of a few minutes after exposure. The differences observed between the two individuals (less auditory fatigue in the dolphin that exhibited the conditioned attenuation) support the hypothesis that conditioned attenuation is a form of "self-mitigation."
Topics: Animals; Auditory Fatigue; Dolphins; Hearing; Sound
PubMed: 38535629
DOI: 10.1121/10.0025387 -
International Journal of Occupational... Jan 2018To determine whether call center dispatchers wearing headsets are subject to auditory fatigue at the end of a work shift.
OBJECTIVES
To determine whether call center dispatchers wearing headsets are subject to auditory fatigue at the end of a work shift.
MATERIAL AND METHODS
Data was gathered at times when call centers were busiest. All call operators wore a headset for up to 12 h. Acoustic environment and noise exposure under the headset were continuously recorded during the entire work shift. Variations in auditory parameters were assessed using pure-tone air-conduction audiometry and an objective test based on distortion product otoacoustic emissions - contralateral suppression of distortion product otoacoustic emission (DPOAE) amplitudes (EchoScan test). Thirty-nine operators and 16 controls, all volunteers, were selected from 3 call centers (sales, assistance, and emergency) where all cognitive tasks were accomplished by phone and on computers.
RESULTS
No acoustic shock was detected during the investigation. The highest normalized noise exposure (daily noise exposure level - L) measured was 75.5 dBA. No significant variation in auditory performances was detected with either pure-tone air-conduction audiometry or the EchoScan test. Nevertheless, dispatchers expressed a feeling of tiredness.
CONCLUSIONS
For an equivalent diffuse field noise exposure, the use of a headset does not seem to worsen auditory fatigue for call center operators. The dispatcher's fatigue was probably due to the duration of the work shift or to the tasks they performed rather than to the noise exposure under a headset. Int J Occup Med Environ Health 2018;31(2):217-226.
Topics: Adult; Audiometry, Pure-Tone; Auditory Fatigue; Computers; Fatigue; France; Hearing Loss, Noise-Induced; Hotlines; Humans; Middle Aged; Noise; Noise, Occupational; Otoacoustic Emissions, Spontaneous; Telephone
PubMed: 29072709
DOI: 10.13075/ijomeh.1896.01131 -
Acta Oto-laryngologica 1985Neuroactive polypeptides such as substance P and enkephalin have recently been demonstrated in the neuronal elements of the inner ear. It has been suggested that the... (Review)
Review
Neuroactive polypeptides such as substance P and enkephalin have recently been demonstrated in the neuronal elements of the inner ear. It has been suggested that the same neuropeptides have a transmitter role in various sensory systems. Transmitter roles for the neuropeptides in the cochlear processes could provide new explanations for many physiological phenomena of hearing. The neuropeptides are particularly well suited to explain such a noise-induced auditory overloading condition as temporary threshold shift.
Topics: Animals; Auditory Fatigue; Axonal Transport; Biophysical Phenomena; Biophysics; Cochlea; Enkephalins; Guinea Pigs; Hair Cells, Auditory; Hair Cells, Auditory, Inner; Humans; Nerve Tissue Proteins; Neurons, Afferent; Neurons, Efferent; Rabbits; Substance P; Synapses; Synaptic Transmission; Vestibulocochlear Nerve
PubMed: 2409739
DOI: 10.3109/00016488509108923 -
The Journal of Speech and Hearing... Dec 1958
Topics: Auditory Fatigue; Hearing; Hearing Tests
PubMed: 13599150
DOI: 10.1044/jshr.0104.299 -
Computational and Mathematical Methods... 2015Noise induced hearing loss (NIHL) remains as a severe health problem worldwide. Existing noise metrics and modeling for evaluation of NIHL are limited on prediction of...
Noise induced hearing loss (NIHL) remains as a severe health problem worldwide. Existing noise metrics and modeling for evaluation of NIHL are limited on prediction of gradually developing NIHL (GDHL) caused by high-level occupational noise. In this study, we proposed two auditory fatigue based models, including equal velocity level (EVL) and complex velocity level (CVL), which combine the high-cycle fatigue theory with the mammalian auditory model, to predict GDHL. The mammalian auditory model is introduced by combining the transfer function of the external-middle ear and the triple-path nonlinear (TRNL) filter to obtain velocities of basilar membrane (BM) in cochlea. The high-cycle fatigue theory is based on the assumption that GDHL can be considered as a process of long-cycle mechanical fatigue failure of organ of Corti. Furthermore, a series of chinchilla experimental data are used to validate the effectiveness of the proposed fatigue models. The regression analysis results show that both proposed fatigue models have high corrections with four hearing loss indices. It indicates that the proposed models can accurately predict hearing loss in chinchilla. Results suggest that the CVL model is more accurate compared to the EVL model on prediction of the auditory risk of exposure to hazardous occupational noise.
Topics: Animals; Auditory Fatigue; Basilar Membrane; Biomechanical Phenomena; Chinchilla; Computational Biology; Disease Models, Animal; Evoked Potentials, Auditory; Hearing Loss, Noise-Induced; Humans; Models, Biological; Noise; Nonlinear Dynamics; Occupational Exposure
PubMed: 26691685
DOI: 10.1155/2015/753864 -
Acta Oto-laryngologica 1951
Topics: Adaptation, Physiological; Auditory Fatigue; Hearing; Hearing Tests
PubMed: 14914517
DOI: 10.3109/00016485109138913 -
Acta Oto-rhino-laryngologica Belgica 1952
Topics: Auditory Fatigue; Hearing; Hearing Tests
PubMed: 14952274
DOI: No ID Found -
The Laryngoscope Mar 1958
Topics: Auditory Fatigue; Hearing Loss, Noise-Induced; Noise; Occupational Diseases
PubMed: 13551111
DOI: 10.1002/lary.5540680349