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The Journal of the Acoustical Society... Nov 2008A survey of papers using auditory evoked potentials (AEPs) published over the last 10 years (Table I) demonstrates that most AEP studies in animals have used subjective...
A survey of papers using auditory evoked potentials (AEPs) published over the last 10 years (Table I) demonstrates that most AEP studies in animals have used subjective methods for auditory threshold determination. Subjective methods greatly reduce the value of statistical hypothesis testing and jeopardize tests of hypothetical experimental group differences in hearing sensitivity. Correspondingly, many attempts have been made to develop objective threshold determination methods, but these have not been used widely. Further, they seldom include an appreciation of the effects of residual noise in the AEP. In this study, AEPs evoked by tonal and noise stimuli in goldfish (Carassius auratus) were recorded and the residual background noise was measured and analyzed in detail. High variability was found in residual noise, but can be effectively controlled with a simple modification of averaging routines. Considerable interobserver disagreements were found using subjective threshold estimation. An objective method of threshold determination was developed based on comparison between AEP amplitude and controlled residual noise, using a signal detection theory approach to set specific threshold criteria. The usefulness of AEP in hypothesis testing for auditory function requires more control over residual background noise amplitudes and the use of objective threshold determination techniques.
Topics: Acoustic Stimulation; Animals; Audiometry, Pure-Tone; Auditory Threshold; Evoked Potentials, Auditory; Goldfish; Hearing; Noise; Sensitivity and Specificity
PubMed: 19045791
DOI: 10.1121/1.2982366 -
Acta Otorhinolaryngologica Italica :... Aug 2018Hearing threshold identification in very young children is always problematic and challenging. Electrophysiological testing such as auditory brainstem responses (ABR) is...
Hearing threshold identification in very young children is always problematic and challenging. Electrophysiological testing such as auditory brainstem responses (ABR) is still considered the most reliable technique for defining the hearing threshold. However, over recent years there has been increasing evidence to support the role of auditory steady-state response (ASSR). Retrospective study. Forty-two children, age range 3-189 months, were evaluated for a total of 83 ears. All patients were affected by sensorineural hearing loss (thresholds ≥ 40 dB HL according to a click-ABR assessment). All patients underwent ABRs, ASSR and pure tone audiometry (PTA), with the latter performed according to the child's mental and physical development. Subjects were divided into two groups: A and B. The latter performed all hearing investigations at the same time as they were older than subjects in group A, and it was then possible to achieve electrophysiological and PTA tests in close temporal sequence. There was no significant difference between the threshold levels identified at the frequencies tested (0.25, 0.5, 1, 2 and 4 kHz), by PTA, ABR and ASSR between the two groups (Mann Whitney U test, p < 0.05). Moreover, for group A, there was no significant difference between the ASSR and ABR thresholds when the children were very young and the PTA thresholds subsequently identified at a later stage. Our results show that ASSR can be considered an effective procedure and a reliable test, particularly when predicting hearing threshold in very young children at lower frequencies (including 0.5 kHz).
Topics: Adolescent; Audiometry; Auditory Threshold; Child; Child, Preschool; Female; Hearing Loss, Sensorineural; Humans; Infant; Male; Retrospective Studies
PubMed: 30197427
DOI: 10.14639/0392-100X-1463 -
Brazilian Journal of Otorhinolaryngology 2022Noise-induced hearing loss is one of the most common forms of sensorineural hearing loss. Nevertheless, the mechanisms of noise-induced hearing loss are still not fully...
INTRODUCTION
Noise-induced hearing loss is one of the most common forms of sensorineural hearing loss. Nevertheless, the mechanisms of noise-induced hearing loss are still not fully understood.
OBJECTIVE
To investigate the dynamics of inflammatory responses in the mammalian cochlea following noise trauma at two different times, once during the light cycle and once during the dark.
METHODS
We challenged C57BL/6J mice with moderate, continuous noise trauma at either 9 a.m. or 9 p.m. Auditory function, histological changes in hair cells, and modifications in gene expression levels of inflammatory mediators were assessed at specific time points. Shifts in auditory brainstem response thresholds were measured at 1, 3, 7 and 14 days after noise exposure to measure potential noise-induced hearing loss. Cochlear basilar-membrane immunofluorescent staining was performed at 3 and 14 days after noise exposure. The mRNA levels of several inflammatory mediators were measured via quantitative real-time polymerase chain reaction before (pre) and after (0, 3, 12, 24 and 72 h) noise exposure.
RESULTS
We found that all noise-exposed mice developed a temporary threshold shift and that there were no significant differences between daytime and nighttime noise exposures in terms of inducing hearing-threshold shifts. Similarly, we did not detect significant histological changes in hair cells between these two groups. However, we discovered an interesting phenomenon in that the peak mRNA levels of IL-1β, IL-6, CCL2 and TNF-α were higher in day noise-exposed mice compared to those in night noise-exposed mice, and these mRNA levels subsided more slowly in day noise-exposed mice.
CONCLUSION
Overall, these observations suggest that the circadian timing of noise exposure has a significant effect on noise-induced inflammatory responses in the mouse cochlea and that a greater inflammatory response might occur after daytime exposure.
Topics: Mice; Animals; Hearing Loss, Noise-Induced; Auditory Threshold; Evoked Potentials, Auditory, Brain Stem; Mice, Inbred C57BL; Cochlea; Inflammation Mediators; RNA, Messenger; Mammals
PubMed: 34217678
DOI: 10.1016/j.bjorl.2021.05.010 -
Hearing Research Apr 2022There is a large amount of variability in performance in masked-speech reception tasks, as well as in psychophysical auditory temporal processing tasks, between...
There is a large amount of variability in performance in masked-speech reception tasks, as well as in psychophysical auditory temporal processing tasks, between listeners with normal or relatively normal low-frequency hearing. In this study we used a cross-sectional dataset collected on 102 listeners (34 young, 34 middle-aged, 34 older) to assess whether variance in these tasks could be explained by variance in subcortical electrophysiological measures of auditory function (auditory brainstem responses and frequency following responses), and whether variance in speech-reception performance could be explained by variance in auditory temporal processing tasks. The potential confounding effect of high-frequency sensitivity was strictly controlled for by using highpass masking noise. Because each high-level construct (masked-speech reception, auditory temporal processing, and subcortical electrophysiological function) was indexed by several variables, we used principal component analyses to reduce the dimensionality of the dataset. Multiple-regression models were then used to assess the associations between the extracted principal components while controlling for a range of possible confounders including age and audiometric thresholds. We found that masked-speech reception was credibly associated with psychophysical auditory temporal processing abilities. No credible associations were found between masked-speech reception and electrophysiological measures of subcortical auditory function, or between psychophysical measures of auditory temporal processing and electrophysiological measures of subcortical auditory function. These results suggest that either the electrophysiological measures of subcortical auditory function used were not sufficiently sensitive to the subcortical neural processes limiting performance in the speech-reception and psychophysical auditory temporal-processing tasks, or that variance in these tasks is largely unrelated to variance in subcortical neural processes in listeners with near-normal hearing.
Topics: Auditory Threshold; Cross-Sectional Studies; Hearing; Humans; Middle Aged; Perceptual Masking; Speech; Speech Perception; Time Perception
PubMed: 35149333
DOI: 10.1016/j.heares.2022.108456 -
Scientific Reports May 2023Deterrents that use acoustics to guide fish away from dangerous areas depend on the elicitation of avoidance in the target species. Acoustic deterrents select the...
Deterrents that use acoustics to guide fish away from dangerous areas depend on the elicitation of avoidance in the target species. Acoustic deterrents select the optimum frequency based on an assumption that highest avoidance is likely to occur at the greatest sensitivity. However, such an assumption may be unfounded. Using goldfish (Carassius auratus) as a suitable experimental model, this study tested this as a null hypothesis. Under laboratory conditions, the deterrence thresholds of individual goldfish exposed to 120 ms tones at six frequencies (250-2000 Hz) and four Sound Pressure Levels (SPL 115-145 dB) were quantified. The deterrence threshold defined as the SPL at which 25% of the tested population startled was calculated and compared to the hearing threshold obtained using Auditory Evoked Potential and particle acceleration threshold data. The optimum frequency to elicit a startle response was 250 Hz; different from the published hearing and particle acceleration sensitivities based on audiograms. The difference between the deterrence threshold and published hearing threshold data varied from 47.1 dB at 250 Hz to 76 dB at 600 Hz. This study demonstrates that information obtained from audiograms may poorly predict the most suitable frequencies at which avoidance behaviours are elicited in fish.
Topics: Animals; Acoustic Stimulation; Auditory Threshold; Hearing; Evoked Potentials, Auditory; Fishes; Acoustics
PubMed: 37202429
DOI: 10.1038/s41598-023-33423-5 -
CoDAS May 2017To verify the auditory processing abilities and occurrence of the suppression effect of Otoacoustic Emissions (OAE) in individuals who stutter. (Observational Study)
Observational Study
PURPOSE
To verify the auditory processing abilities and occurrence of the suppression effect of Otoacoustic Emissions (OAE) in individuals who stutter.
METHODS
The study sample comprised 15 adult individuals who stutter, aged 18-40 years, with stuttering severity ranging from mild to severe, paired according to gender, age, and schooling with individuals without speech complaint or disorder. All participants underwent conventional clinical evaluation, specific stuttering assessment, and basic (audiometry, imitanciometry, and measurement of acoustic reflexes) and specific (auditory processing evaluation and measurement of suppression effect of OAEs) audiological assessments. Data were statistically analyzed with application of the Fisher's Exact Test and the Mann-Whitney Test.
RESULTS
The group of individuals who stutter (Study Group - SG) presented higher incidence of auditory processing disorders. The auditory processing assessments used to differentiate the groups of stutterers and non-stutterers (Control Group - CG) were the Nonverbal Dichotic Test and the Frequency Pattern Test. The SG presented higher incidence of absence of suppression effect of OAEs, indicating abnormal functioning of the efferent medial olivocochlear system.
CONCLUSION
The auditory processing abilities investigated in this study differentiate individuals who stutter from non-stutterers, with greater changes in the first. Functioning of the efferent medial olivocochlear system showed a deficit in stutterers, indicating difficulties in auditory discrimination, especially in the presence of noise.
Topics: Adolescent; Adult; Auditory Perception; Auditory Threshold; Cross-Sectional Studies; Educational Status; Female; Humans; Male; Otoacoustic Emissions, Spontaneous; Stuttering; Young Adult
PubMed: 28538833
DOI: 10.1590/2317-1782/20172016230 -
PloS One 2015The objective was to evaluate the association of peripheral and central hearing abilities with cognitive function in older adults.
OBJECTIVE
The objective was to evaluate the association of peripheral and central hearing abilities with cognitive function in older adults.
METHODS
Recruited from epidemiological studies of aging and cognition at the Rush Alzheimer's Disease Center, participants were a community-dwelling cohort of older adults (range 63-98 years) without diagnosis of dementia. The cohort contained roughly equal numbers of Black (n=61) and White (n=63) subjects with groups similar in terms of age, gender, and years of education. Auditory abilities were measured with pure-tone audiometry, speech-in-noise perception, and discrimination thresholds for both static and dynamic spectral patterns. Cognitive performance was evaluated with a 12-test battery assessing episodic, semantic, and working memory, perceptual speed, and visuospatial abilities.
RESULTS
Among the auditory measures, only the static and dynamic spectral-pattern discrimination thresholds were associated with cognitive performance in a regression model that included the demographic covariates race, age, gender, and years of education. Subsequent analysis indicated substantial shared variance among the covariates race and both measures of spectral-pattern discrimination in accounting for cognitive performance. Among cognitive measures, working memory and visuospatial abilities showed the strongest interrelationship to spectral-pattern discrimination performance.
CONCLUSIONS
For a cohort of older adults without diagnosis of dementia, neither hearing thresholds nor speech-in-noise ability showed significant association with a summary measure of global cognition. In contrast, the two auditory metrics of spectral-pattern discrimination ability significantly contributed to a regression model prediction of cognitive performance, demonstrating association of central auditory ability to cognitive status using auditory metrics that avoided the confounding effect of speech materials.
Topics: Acoustic Stimulation; Aged; Aged, 80 and over; Aging; Audiometry, Pure-Tone; Auditory Threshold; Cognition; Female; Hearing; Humans; Male; Middle Aged; Neuropsychological Tests
PubMed: 26237423
DOI: 10.1371/journal.pone.0134330 -
Comparative Biochemistry and... Nov 2021Temperature affects various metabolic and physiological processes in ectothermic animals, including auditory systems. The current study investigates the effect of...
Temperature affects various metabolic and physiological processes in ectothermic animals, including auditory systems. The current study investigates the effect of temperature and thermal acclimation time on hearing sensitivities in a eurythermal and a stenothermal fish possessing accessory hearing structures. Using the auditory evoked potential (AEP) recording technique, we determined thresholds from 0.1 to 4 kHz and peak latencies of AEP-waveforms in response to a click stimulus. The goldfish Carassius auratus was chosen as a model for eurythermal and the Amazonian catfish Megalodoras uranoscopus as a model for stenothermal species. Both species were tested at two different temperatures (C. auratus: 15 °C and 25 °C, M. uranoscopus: 22 °C and 30 °C) and acclimation periods, within 22 h (unacclimated) or three to four weeks (acclimated) after reaching the target temperature. A frequency-dependent increase in auditory sensitivity and a decrease of peak latencies was recorded in both species at higher temperatures, independent of acclimation time. The change in hearing thresholds per degree Celsius was more pronounced in the stenothermal catfish. The data indicate that higher temperatures improved hearing (lower thresholds, shorter latencies), whereas acclimation had no effect on hearing in either species. The latter data contradict previous findings in the eurythermal channel catfish Ictalurus punctatus in which acclimation slightly improved hearing when raising the temperatures. A comparison of changes in hearing sensitivity per degree Celsius of all seven species tested so far revealed no differences between eurythermal and stenothermal species.
Topics: Adaptation, Physiological; Animals; Auditory Threshold; Fishes; Hearing; Reaction Time; Temperature
PubMed: 34375742
DOI: 10.1016/j.cbpa.2021.111053 -
Journal of the Association For Research... Aug 2022We describe a scalp-recorded measure of tonotopic selectivity, the "cortical onset response" (COR) and compare the results between humans and cats. The COR results, in...
We describe a scalp-recorded measure of tonotopic selectivity, the "cortical onset response" (COR) and compare the results between humans and cats. The COR results, in turn, were compared with psychophysical masked-detection thresholds obtained using similar stimuli and obtained from both species. The COR consisted of averaged responses elicited by 50-ms tone-burst probes presented at 1-s intervals against a continuous noise masker. The noise masker had a bandwidth of 1 or 1/8th octave, geometrically centred on 4000 Hz for humans and on 8000 Hz for cats. The probe frequency was either - 0.5, - 0.25, 0, 0.25 or 0.5 octaves re the masker centre frequency. The COR was larger for probe frequencies more distant from the centre frequency of the masker, and this effect was greater for the 1/8th-octave than for the 1-octave masker. This pattern broadly reflected the masked excitation patterns obtained psychophysically with similar stimuli in both species. However, the positive signal-to-noise ratio used to obtain reliable COR measures meant that some aspects of the data differed from those obtained psychophysically, in a way that could be partly explained by the upward spread of the probe's excitation pattern. Our psychophysical measurements also showed that the auditory filter width obtained at 8000 Hz using notched-noise maskers was slightly wider in cat than previous measures from humans. We argue that although conclusions from COR measures differ in some ways from conclusions based on psychophysics, the COR measures provide an objective, noninvasive, valid measure of tonotopic selectivity that does not require training and that may be applied to acoustic and cochlear-implant experiments in humans and laboratory animals.
Topics: Animals; Auditory Threshold; Cats; Electrophysiology; Humans; Noise; Perceptual Masking; Psychophysics
PubMed: 35697952
DOI: 10.1007/s10162-022-00851-5 -
Brain Stimulation 2023Transcranial ultrasound stimulation (TUS) is a promising noninvasive neuromodulation modality. The inadvertent and unpredictable activation of the auditory system in...
BACKGROUND
Transcranial ultrasound stimulation (TUS) is a promising noninvasive neuromodulation modality. The inadvertent and unpredictable activation of the auditory system in response to TUS obfuscates the interpretation of non-auditory neuromodulatory responses.
OBJECTIVE
The objective was to develop and validate a computational metric to quantify the susceptibility to unintended auditory brainstem response (ABR) in mice premised on time frequency analyses of TUS signals and auditory sensitivity.
METHODS
Ultrasound pulses with varying amplitudes, pulse repetition frequencies (PRFs), envelope smoothing profiles, and sinusoidal modulation frequencies were selected. Each pulse's time-varying frequency spectrum was differentiated across time, weighted by the mouse hearing sensitivity, then summed across frequencies. The resulting time-varying function, computationally predicting the ABR, was validated against experimental ABR in mice during TUS with the corresponding pulse.
RESULTS
There was a significant correlation between experimental ABRs and the computational predictions for 19 TUS signals (R = 0.97).
CONCLUSIONS
To reduce ABR in mice during in vivo TUS studies, 1) reduce the amplitude of a rectangular continuous wave envelope, 2) increase the rise/fall times of a smoothed continuous wave envelope, and/or 3) change the PRF and/or duty cycle of a rectangular or sinusoidal pulsed wave to reduce the gap between pulses and increase the rise/fall time of the overall envelope. This metric can aid researchers performing in vivo mouse studies in selecting TUS signal parameters that minimize unintended ABR. The methods for developing this metric can be adapted to other animal models.
Topics: Mice; Animals; Evoked Potentials, Auditory, Brain Stem; Auditory Threshold; Hearing; Acoustic Stimulation
PubMed: 37690602
DOI: 10.1016/j.brs.2023.09.004