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Sample records for auditory threshold

  1. [Auditory threshold for white noise].

    Science.gov (United States)

    Carrat, R; Thillier, J L; Durivault, J

    1975-01-01

    The liminal auditory threshold for white noise and for coloured noise was determined from a statistical survey of a group of 21 young people with normal hearing. The normal auditory threshold for white noise with a spectrum covering the whole of the auditory field is between -- 0.57 dB +/- 8.78. The normal auditory threshold for bands of filtered white noise (coloured noise with a central frequency corresponding to the pure frequencies usually employed in tonal audiometry) describes a typical curve which, instead of being homothetic to the usual tonal curves, sinks to low frequencies and then rises. The peak of this curve is replaced by a broad plateau ranging from 750 to 6000 Hz and contained in the concavity of the liminal tonal curves. The ear is therefore less sensitive but, at limited acoustic pressure, white noise first impinges with the same discrimination upon the whole of the conversational zone of the auditory field. Discovery of the audiometric threshold for white noise constitutes a synthetic method of measuring acuteness of hearing which considerably reduces the amount of manipulation required.

  2. Regenerative capacity of auditory persistent threshold shift

    Energy Technology Data Exchange (ETDEWEB)

    Szadkowski, D.; Harries, M.; Deubel, B.

    1981-12-01

    It was the subject of the examination to find out to what extent a holiday would influence the auditory persistent threshold shift of 48 noise-exposed dockers and 20 other examined persons not exposed to noise in their professional life. For assessing the noise exposition, the equivalent permanent noise level according to 'VDI 2058' or 'TA noise' was ascertained with respect to the predominant intermittent noise character. With reference to noise intensity the 48 dockers were divided into two groups: group I (75 to 87 db(A)), group II (87 to 102 db(A)). The control collective was associated to group III. All persons to be examined were audiometrized before and after beginning of work, after a noise abstinence of at least 14 hours. Only the auditions via aerial transmission in the frequencies 1, 2, 3, 4, 6 and 8 kHz was measured. Basing on the obtained results it was ascertained that in group I as well as group II an audiometric improvement after the holiday could clearly be proved. The results justify the assumption that - contrary to previous conception in scientific literature - a so-called noise injury is still improvable after a longer holiday of approximately four weeks.

  3. Thresholding of auditory cortical representation by background noise

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    Liang, Feixue; Bai, Lin; Tao, Huizhong W.; Zhang, Li I.; Xiao, Zhongju

    2014-01-01

    It is generally thought that background noise can mask auditory information. However, how the noise specifically transforms neuronal auditory processing in a level-dependent manner remains to be carefully determined. Here, with in vivo loose-patch cell-attached recordings in layer 4 of the rat primary auditory cortex (A1), we systematically examined how continuous wideband noise of different levels affected receptive field properties of individual neurons. We found that the background noise, when above a certain critical/effective level, resulted in an elevation of intensity threshold for tone-evoked responses. This increase of threshold was linearly dependent on the noise intensity above the critical level. As such, the tonal receptive field (TRF) of individual neurons was translated upward as an entirety toward high intensities along the intensity domain. This resulted in preserved preferred characteristic frequency (CF) and the overall shape of TRF, but reduced frequency responding range and an enhanced frequency selectivity for the same stimulus intensity. Such translational effects on intensity threshold were observed in both excitatory and fast-spiking inhibitory neurons, as well as in both monotonic and nonmonotonic (intensity-tuned) A1 neurons. Our results suggest that in a noise background, fundamental auditory representations are modulated through a background level-dependent linear shifting along intensity domain, which is equivalent to reducing stimulus intensity. PMID:25426029

  4. Thresholding of auditory cortical representation by background noise.

    Science.gov (United States)

    Liang, Feixue; Bai, Lin; Tao, Huizhong W; Zhang, Li I; Xiao, Zhongju

    2014-01-01

    It is generally thought that background noise can mask auditory information. However, how the noise specifically transforms neuronal auditory processing in a level-dependent manner remains to be carefully determined. Here, with in vivo loose-patch cell-attached recordings in layer 4 of the rat primary auditory cortex (A1), we systematically examined how continuous wideband noise of different levels affected receptive field properties of individual neurons. We found that the background noise, when above a certain critical/effective level, resulted in an elevation of intensity threshold for tone-evoked responses. This increase of threshold was linearly dependent on the noise intensity above the critical level. As such, the tonal receptive field (TRF) of individual neurons was translated upward as an entirety toward high intensities along the intensity domain. This resulted in preserved preferred characteristic frequency (CF) and the overall shape of TRF, but reduced frequency responding range and an enhanced frequency selectivity for the same stimulus intensity. Such translational effects on intensity threshold were observed in both excitatory and fast-spiking inhibitory neurons, as well as in both monotonic and nonmonotonic (intensity-tuned) A1 neurons. Our results suggest that in a noise background, fundamental auditory representations are modulated through a background level-dependent linear shifting along intensity domain, which is equivalent to reducing stimulus intensity.

  5. Thresholding of Auditory Cortical Representation by Background Noise

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    Feixue eLiang

    2014-11-01

    Full Text Available It is generally thought that background noise can mask auditory information. However, how the noise specifically transforms neuronal auditory processing in a level-dependent manner remains to be carefully determined. Here, with in vivo loose-patch cell-attached recordings in layer 4 of the rat primary auditory cortex (A1, we systematically examined how continuous wideband noise of different levels affected receptive field properties of individual neurons. We found that the background noise, when above a certain critical/effective level, resulted in an elevation of intensity threshold for tone-evoked responses. This increase of threshold was linearly dependent on the noise intensity above the critical level. As such, the tonal receptive field of individual neurons was translated upward as an entirety toward high intensities along the intensity domain. This resulted in preserved preferred characteristic frequency and the overall shape of tonal receptive field, but reduced frequency responding range and an enhanced frequency selectivity for the same stimulus intensity. Such translational effects on intensity threshold were observed in both excitatory and fast-spiking inhibitory neurons, as well as in both monotonic and nonmonotonic (intensity-tuned A1 neurons. Our results suggest that in a noise background, fundamental auditory representations are modulated through a background level-dependent linear shifting along intensity domain, which is equivalent to reducing stimulus intensity.

  6. Stochastic undersampling steepens auditory threshold/duration functions: Implications for understanding auditory deafferentation and aging

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    Frederic eMarmel

    2015-05-01

    Full Text Available It has long been known that some listeners experience hearing difficulties out of proportion with their audiometric losses. Notably, some older adults as well as auditory neuropathy patients have temporal-processing and speech-in-noise intelligibility deficits not accountable for by elevated audiometric thresholds. The study of these hearing deficits has been revitalized by recent studies that show that auditory deafferentation comes with aging and can occur even in the absence of an audiometric loss. The present study builds on the stochastic undersampling principle proposed by Lopez-Poveda and Barrios (2013 to account for the perceptual effects of auditory deafferentation. Auditory threshold/duration functions were measured for broadband noises that were stochastically undersampled to various different degrees. Stimuli with and without undersampling were equated for overall energy in order to focus on the changes that undersampling elicited on the stimulus waveforms, and not on its effects on the overall stimulus energy. Stochastic undersampling impaired the detection of short sounds ( 50 ms did not change or improved, depending on the degree of undersampling. The results for short sounds show that stochastic undersampling, and hence presumably deafferentation, can account for the steeper threshold/duration functions observed in auditory neuropathy patients and older adults with (near normal audiometry. This suggests that deafferentation might be diagnosed using pure-tone audiometry with short tones. It further suggests that that the auditory system of audiometrically normal older listeners might not be ‘slower than normal’, as is commonly thought, but simply less well afferented. Finally, the results for both short and long sounds support the probabilistic theories of detectability that challenge the idea that auditory threshold occurs by integration of sound energy over time.

  7. Modeling of Auditory Neuron Response Thresholds with Cochlear Implants

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    Frederic Venail

    2015-01-01

    Full Text Available The quality of the prosthetic-neural interface is a critical point for cochlear implant efficiency. It depends not only on technical and anatomical factors such as electrode position into the cochlea (depth and scalar placement, electrode impedance, and distance between the electrode and the stimulated auditory neurons, but also on the number of functional auditory neurons. The efficiency of electrical stimulation can be assessed by the measurement of e-CAP in cochlear implant users. In the present study, we modeled the activation of auditory neurons in cochlear implant recipients (nucleus device. The electrical response, measured using auto-NRT (neural responses telemetry algorithm, has been analyzed using multivariate regression with cubic splines in order to take into account the variations of insertion depth of electrodes amongst subjects as well as the other technical and anatomical factors listed above. NRT thresholds depend on the electrode squared impedance (β = −0.11 ± 0.02, P<0.01, the scalar placement of the electrodes (β = −8.50 ± 1.97, P<0.01, and the depth of insertion calculated as the characteristic frequency of auditory neurons (CNF. Distribution of NRT residues according to CNF could provide a proxy of auditory neurons functioning in implanted cochleas.

  8. Towards a unifying basis of auditory thresholds: binaural summation.

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    Heil, Peter

    2014-04-01

    Absolute auditory threshold decreases with increasing sound duration, a phenomenon explainable by the assumptions that the sound evokes neural events whose probabilities of occurrence are proportional to the sound's amplitude raised to an exponent of about 3 and that a constant number of events are required for threshold (Heil and Neubauer, Proc Natl Acad Sci USA 100:6151-6156, 2003). Based on this probabilistic model and on the assumption of perfect binaural summation, an equation is derived here that provides an explicit expression of the binaural threshold as a function of the two monaural thresholds, irrespective of whether they are equal or unequal, and of the exponent in the model. For exponents >0, the predicted binaural advantage is largest when the two monaural thresholds are equal and decreases towards zero as the monaural threshold difference increases. This equation is tested and the exponent derived by comparing binaural thresholds with those predicted on the basis of the two monaural thresholds for different values of the exponent. The thresholds, measured in a large sample of human subjects with equal and unequal monaural thresholds and for stimuli with different temporal envelopes, are compatible only with an exponent close to 3. An exponent of 3 predicts a binaural advantage of 2 dB when the two ears are equally sensitive. Thus, listening with two (equally sensitive) ears rather than one has the same effect on absolute threshold as doubling duration. The data suggest that perfect binaural summation occurs at threshold and that peripheral neural signals are governed by an exponent close to 3. They might also shed new light on mechanisms underlying binaural summation of loudness.

  9. Positioning of earphones and variations in auditory thresholds,

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    Bettina Poggi Almeida

    2015-12-01

    Full Text Available ABSTRACT INTRODUCTION: One of the problems observed in pure-tone audiometry tonal has been the variation in test results of a same individual, particularly at frequencies of 4 kHz, 6 kHz and/or 8 kHz. Improper placement of headphones is one of the factors that can cause alterations in results. OBJECTIVE: To compare differences in auditory thresholds using earphones positioned by the examiner and by the worker. METHODS: Clinical and experimental study conducted in 2009, with 324 workers aged between 19 and 61 years, with a mean of 33.29 years and mean exposure time of 7.67 years. All subjects were familiar with audiometry procedures. Auditory thresholds were obtained at frequencies of 0.25-8 kHz, with earphones positioned by the examiners, and at frequencies of 4, 6 and 8 kHz, with earphones placed by workers in a comfortable position, following the examiner's instructions. The thresholds obtained in these two situations were compared. RESULTS: The three frequencies exhibited better responses with earphones placed by the workers themselves (p < 0.001. At a frequency of 8 kHz a greater difference was found (p < 0.001, with a mean of 13.89 dB and standard deviation of 6.07 dB. CONCLUSION: Earphone placement by the workers themselves under supervision of the examiner results in improved mean auditory thresholds at frequencies of 4, 6 and 8 kHz, the last one significantly higher than the other two.

  10. Positioning of earphones and variations in auditory thresholds.

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    Almeida, Bettina Poggi; Menezes, Pedro de Lemos; Andrade, Kelly Cristina Lira de; Teixeira, Cleide Fernandes

    2015-01-01

    One of the problems observed in pure-tone audiometry tonal has been the variation in test results of a same individual, particularly at frequencies of 4kHz, 6kHz and/or 8kHz. Improper placement of headphones is one of the factors that can cause alterations in results. To compare differences in auditory thresholds using earphones positioned by the examiner and by the worker. Clinical and experimental study conducted in 2009, with 324 workers aged between 19 and 61 years, with a mean of 33.29 years and mean exposure time of 7.67 years. All subjects were familiar with audiometry procedures. Auditory thresholds were obtained at frequencies of 0.25-8kHz, with earphones positioned by the examiners, and at frequencies of 4, 6 and 8kHz, with earphones placed by workers in a comfortable position, following the examiner's instructions. The thresholds obtained in these two situations were compared. The three frequencies exhibited better responses with earphones placed by the workers themselves (p<0.001). At a frequency of 8kHz a greater difference was found (p<0.001), with a mean of 13.89dB and standard deviation of 6.07dB. Earphone placement by the workers themselves under supervision of the examiner results in improved mean auditory thresholds at frequencies of 4, 6 and 8kHz, the last one significantly higher than the other two. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  11. The acute effects of alcohol on auditory thresholds.

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    Upile, Tahwinder; Sipaul, Fabian; Jerjes, Waseem; Singh, Sandeep; Nouraei, Seyed Ahmad Reza; El Maaytah, Mohammed; Andrews, Peter; Graham, John; Hopper, Colin; Wright, Anthony

    2007-09-18

    There is very little knowledge about alcohol-induced hearing loss. Alcohol consumption and tolerance to loud noise is a well observed phenomenon as seen in the Western world where parties get noisier by the hour as the evening matures. This leads to increase in the referrals to the "hearing aid clinic" and the diagnosis of "cocktail party deafness" which may not necessarily be only due to presbyacusis or noise-induced hearing loss. 30 healthy volunteers were recruited for this trial which took place in a controlled acoustic environment. Each of the individuals was required to consume a pre-set amount of alcohol and the hearing was tested (using full pure tone audiogram) pre- and post- alcohol consumption over a broad range of 6 frequencies. Volunteers who achieve a minimum breath alcohol threshold level of 30 u/l had to have second audiogram testing. All the volunteers underwent timed psychometric and visuo-spatial skills tests to detect the effect of alcohol on the decision-making and psychomotor co-ordination. Our results showed that there was a positive association between increasing breath alcohol concentration and the magnitude of the increase in hearing threshold for most hearing frequencies. This was calculated by using the Pearson Regression Coefficient Ratio which was up to 0.6 for hearing at 1000 Hz. Over 90% of subjects had raised auditory thresholds in three or more frequencies; this was more marked in the lower frequencies. Alcohol specifically blunts lower frequencies affecting the mostly 1000 Hz, which is the most crucial frequency for speech discrimination. In conclusion alcohol does appear to affect auditory thresholds with some frequencies being more affected than others.

  12. The acute effects of alcohol on auditory thresholds

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    El Maaytah Mohammed

    2007-09-01

    Full Text Available Abstract Background There is very little knowledge about alcohol-induced hearing loss. Alcohol consumption and tolerance to loud noise is a well observed phenomenon as seen in the Western world where parties get noisier by the hour as the evening matures. This leads to increase in the referrals to the "hearing aid clinic" and the diagnosis of "cocktail party deafness" which may not necessarily be only due to presbyacusis or noise-induced hearing loss. Methods 30 healthy volunteers were recruited for this trial which took place in a controlled acoustic environment. Each of the individuals was required to consume a pre-set amount of alcohol and the hearing was tested (using full pure tone audiogram pre- and post- alcohol consumption over a broad range of 6 frequencies. Volunteers who achieve a minimum breath alcohol threshold level of 30 u/l had to have second audiogram testing. All the volunteers underwent timed psychometric and visuo-spatial skills tests to detect the effect of alcohol on the decision-making and psychomotor co-ordination. Results Our results showed that there was a positive association between increasing breath alcohol concentration and the magnitude of the increase in hearing threshold for most hearing frequencies. This was calculated by using the Pearson Regression Coefficient Ratio which was up to 0.6 for hearing at 1000 Hz. Over 90% of subjects had raised auditory thresholds in three or more frequencies; this was more marked in the lower frequencies. Conclusion Alcohol specifically blunts lower frequencies affecting the mostly 1000 Hz, which is the most crucial frequency for speech discrimination. In conclusion alcohol does appear to affect auditory thresholds with some frequencies being more affected than others.

  13. Auditory brainstem responses predict auditory nerve fiber thresholds and frequency selectivity in hearing impaired chinchillas.

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    Henry, Kenneth S; Kale, Sushrut; Scheidt, Ryan E; Heinz, Michael G

    2011-10-01

    Noninvasive auditory brainstem responses (ABRs) are commonly used to assess cochlear pathology in both clinical and research environments. In the current study, we evaluated the relationship between ABR characteristics and more direct measures of cochlear function. We recorded ABRs and auditory nerve (AN) single-unit responses in seven chinchillas with noise-induced hearing loss. ABRs were recorded for 1-8 kHz tone burst stimuli both before and several weeks after 4 h of exposure to a 115 dB SPL, 50 Hz band of noise with a center frequency of 2 kHz. Shifts in ABR characteristics (threshold, wave I amplitude, and wave I latency) following hearing loss were compared to AN-fiber tuning curve properties (threshold and frequency selectivity) in the same animals. As expected, noise exposure generally resulted in an increase in ABR threshold and decrease in wave I amplitude at equal SPL. Wave I amplitude at equal sensation level (SL), however, was similar before and after noise exposure. In addition, noise exposure resulted in decreases in ABR wave I latency at equal SL and, to a lesser extent, at equal SPL. The shifts in ABR characteristics were significantly related to AN-fiber tuning curve properties in the same animal at the same frequency. Larger shifts in ABR thresholds and ABR wave I amplitude at equal SPL were associated with greater AN threshold elevation. Larger reductions in ABR wave I latency at equal SL, on the other hand, were associated with greater loss of AN frequency selectivity. This result is consistent with linear systems theory, which predicts shorter time delays for broader peripheral frequency tuning. Taken together with other studies, our results affirm that ABR thresholds and wave I amplitude provide useful estimates of cochlear sensitivity. Furthermore, comparisons of ABR wave I latency to normative data at the same SL may prove useful for detecting and characterizing loss of cochlear frequency selectivity. Copyright © 2011 Elsevier B.V. All

  14. Auditory spectral versus spatial temporal order judgment: Threshold distribution analysis.

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    Fostick, Leah; Babkoff, Harvey

    2017-05-01

    Some researchers suggested that one central mechanism is responsible for temporal order judgments (TOJ), within and across sensory channels. This suggestion is supported by findings of similar TOJ thresholds in same modality and cross-modality TOJ tasks. In the present study, we challenge this idea by analyzing and comparing the threshold distributions of the spectral and spatial TOJ tasks. In spectral TOJ, the tones differ in their frequency ("high" and "low") and are delivered either binaurally or monaurally. In spatial (or dichotic) TOJ, the two tones are identical but are presented asynchronously to the two ears and thus differ with respect to which ear received the first tone and which ear received the second tone ("left"/"left"). Although both tasks are regarded as measures of auditory temporal processing, a review of data published in the literature suggests that they trigger different patterns of response. The aim of the current study was to systematically examine spectral and spatial TOJ threshold distributions across a large number of studies. Data are based on 388 participants in 13 spectral TOJ experiments, and 222 participants in 9 spatial TOJ experiments. None of the spatial TOJ distributions deviated significantly from the Gaussian; while all of the spectral TOJ threshold distributions were skewed to the right, with more than half of the participants accurately judging temporal order at very short interstimulus intervals (ISI). The data do not support the hypothesis that 1 central mechanism is responsible for all temporal order judgments. We suggest that different perceptual strategies are employed when performing spectral TOJ than when performing spatial TOJ. We posit that the spectral TOJ paradigm may provide the opportunity for two-tone masking or temporal integration, which is sensitive to the order of the tones and thus provides perceptual cues that may be used to judge temporal order. This possibility should be considered when interpreting

  15. Prolonged noise exposure-induced auditory threshold shifts in rats.

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    Chen, Guang-Di; Decker, Brandon; Krishnan Muthaiah, Vijaya Prakash; Sheppard, Adam; Salvi, Richard

    2014-11-01

    Noise-induced hearing loss (NIHL) initially increases with exposure duration, but eventually reaches an asymptotic threshold shift (ATS) once the exposure duration exceeds 18-24 h. Equations for predicting the ATS have been developed for several species, but not for rats, even though this species is extensively used in noise exposure research. To fill this void, we exposed rats to narrowband noise (NBN, 16-20 kHz) for 5 weeks starting at 80 dB SPL in the first week and then increasing the level by 6 dB per week to a final level of 104 dB SPL. Auditory brainstem responses (ABR) were recorded before, during, and following the exposure to determine the amount of hearing loss. The noise induced threshold shift to continuous long-term exposure, defined as compound threshold shift (CTS), within and above 16-20 kHz increased with noise level at the rate of 1.82 dB threshold shift per dB of noise level (NL) above a critical level (C) of 77.2 dB SPL i.e. CTS = 1.82(NL-77.2). The normalized amplitude of the largest ABR peak measured at 100 dB SPL decreased at the rate of 3.1% per dB of NL above the critical level of 76.9 dB SPL, i.e., %ABR Reduction = 3.1%(NL-76.9). ABR thresholds measured >30 days post-exposure only partially recovered resulting in a permanent threshold shift of 30-40 dB along with severe hair cell loss in the basal, high-frequency region of the cochlea. In the rat, CTS increases with noise level with a slope similar to humans and chinchillas. The critical level (C) in the rat is similar to that of humans, but higher than that of chinchillas. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Auditory temporal-order thresholds show no gender differences

    NARCIS (Netherlands)

    van Kesteren, Marlieke T. R.; Wierslnca-Post, J. Esther C.

    2007-01-01

    Purpose: Several studies on auditory temporal-order processing showed gender differences. Women needed longer inter-stimulus intervals than men when indicating the temporal order of two clicks presented to the left and right ear. In this study, we examined whether we could reproduce these results in

  17. Threshold changes in auditory brainstem response (ABR) due to the administration of kanamycin in dogs.

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    Uzuka, Y; Furuta, T; Yamaoka, M; Ohnishi, T; Tsubone, H; Sugano, S

    1996-10-01

    Auditory brainstem response (ABR) is a useful method in evaluating auditory function in human. To investigate the ABR threshold is more effective than to pursue the trends in each component of ABR. In this study, tone burst sound stimuli were employed and the ABR threshold shift caused by kanamycin administration was investigated in dogs. In a series of monitoring of ABR against short-period auditory lesions, changes in the ABR waveform after intravenous administration of kanamycin were detected. These changes returned gradually and were reversible. The changes in ABR against long-period auditory function disorder were perceived by an increase in the ABR threshold. The ABR threshold shift occurred earlier in the high frequency sounds than in the lower frequency sounds. This is why amino glycoside antibiotics damage the cochlear hair cells in the basal layer and lead to the loss of hearing selectively for high frequency tones. These findings suggest that tracing of the ABR threshold by tone bursts could provide information that has a specificity for frequency in hearing tests and is a useful method in clinical veterinary medicine or/and toxicological tests.

  18. Lutein and zeaxanthin status and auditory thresholds in a sample of young healthy adults.

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    Wong, Jennifer C; Kaplan, Holly S; Hammond, Billy R

    2017-01-01

    Dietary carotenoids lutein (L) and zeaxanthin (Z) have been linked to improved visual and cognitive function. These effects are thought to be mediated by the presence of these pigments in critical regions of the retina and brain. There, it has been postulated that L and Z mediate improved performance by enhancing neural efficiency. The auditory system also relies on efficient segregating of signals and noise and LZ are also found in the auditory cortex. The purpose of the present study was to investigate the influence of LZ status (as assessed by the measuring levels in retina) on auditory thresholds in young non-smokers (N = 32, M = 20.72 ± 3.28 years). LZ status was determined by measuring macular pigment (MP) optical density using a standardized psychophysical technique (customized heterochromatic flicker photometry). Auditory thresholds were assessed with puretone thresholds and puretone auditory thresholds in white noise. MP density was related to many, but not all, of the puretone thresholds we tested: 250 Hz (F(6,32) = 4.36, P < 0.01), 500 Hz (F(6,32) = 2.25, P < 0.05), 1000 Hz (F(6,32) = 3.22, P < 0.05), and 6000 Hz (F(6,32) = 2.56, P < 0.05). The overall pattern of results is consistent with a role for L and Z in maintaining optimal auditory function.

  19. High levels of sound pressure: acoustic reflex thresholds and auditory complaints of workers with noise exposure

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    Alexandre Scalli Mathias Duarte

    2015-08-01

    Full Text Available INTRODUCTION: The clinical evaluation of subjects with occupational noise exposure has been difficult due to the discrepancy between auditory complaints and auditory test results. This study aimed to evaluate the contralateral acoustic reflex thresholds of workers exposed to high levels of noise, and to compare these results to the subjects' auditory complaints.METHODS: This clinical retrospective study evaluated 364 workers between 1998 and 2005; their contralateral acoustic reflexes were compared to auditory complaints, age, and noise exposure time by chi-squared, Fisher's, and Spearman's tests.RESULTS: The workers' age ranged from 18 to 50 years (mean = 39.6, and noise exposure time from one to 38 years (mean = 17.3. We found that 15.1% (55 of the workers had bilateral hearing loss, 38.5% (140 had bilateral tinnitus, 52.8% (192 had abnormal sensitivity to loud sounds, and 47.2% (172 had speech recognition impairment. The variables hearing loss, speech recognition impairment, tinnitus, age group, and noise exposure time did not show relationship with acoustic reflex thresholds; however, all complaints demonstrated a statistically significant relationship with Metz recruitment at 3000 and 4000 Hz bilaterally.CONCLUSION: There was no significance relationship between auditory complaints and acoustic reflexes.

  20. Auditory brainstem response latency in forward masking, a marker of sensory deficits in listeners with normal hearing thresholds

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    Mehraei, Golbarg; Paredes Gallardo, Andreu; Shinn-Cunningham, Barbara G.

    2017-01-01

    In rodent models, acoustic exposure too modest to elevate hearing thresholds can nonetheless cause auditory nerve fiber deafferentation, interfering with the coding of supra-threshold sound. Low-spontaneous rate nerve fibers, important for encoding acoustic information at supra-threshold levels...... and in noise, are more susceptible to degeneration than high-spontaneous rate fibers. The change in auditory brainstem response (ABR) wave-V latency with noise level has been shown to be associated with auditory nerve deafferentation. Here, we measured ABR in a forward masking paradigm and evaluated wave......-V latency changes with increasing masker-to-probe intervals. In the same listeners, behavioral forward masking detection thresholds were measured. We hypothesized that 1) auditory nerve fiber deafferentation increases forward masking thresholds and increases wave-V latency and 2) a preferential loss of low...

  1. Mode of recording and modulation frequency effects of auditory steady state response thresholds.

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    Jalaei, Bahram; Shaabani, Moslem; Zakaria, Mohd Normani

    The performance of auditory steady state response (ASSR) in threshold testing when recorded ipsilaterally and contralaterally, as well as at low and high modulation frequencies (MFs), has not been systematically studied. To verify the influences of mode of recording (ipsilateral vs. contralateral) and modulation frequency (40Hz vs. 90Hz) on ASSR thresholds. Fifteen female and 14 male subjects (aged 18-30 years) with normal hearing bilaterally were studied. Narrow-band CE-chirp(®) stimuli (centerd at 500, 1000, 2000, and 4000Hz) modulated at 40 and 90Hz MFs were presented to the participants' right ear. The ASSR thresholds were then recorded at each test frequency in both ipsilateral and contralateral channels. Due to pronounced interaction effects between mode of recording and MF (p<0.05 by two-way repeated measures ANOVA), mean ASSR thresholds were then compared among four conditions (ipsi-40Hz, ipsi-90Hz, contra-40Hz, and contra-90Hz) using one-way repeated measures ANOVA. At the 500 and 1000Hz test frequencies, contra-40Hz condition produced the lowest mean ASSR thresholds. In contrast, at high frequencies (2000 and 4000Hz), ipsi-90Hz condition revealed the lowest mean ASSR thresholds. At most test frequencies, contra-90Hz produced the highest mean ASSR thresholds. Based on the findings, the present study recommends two different protocols for an optimum threshold testing with ASSR, at least when testing young adults. This includes the use of contra-40Hz recording mode due to its promising performance in hearing threshold estimation. Copyright © 2016 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  2. Audiometric thresholds and auditory processing in children with early malnutrition: a retrospective cohort study

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    Patricia Aparecida Zuanetti

    Full Text Available CONTEXT AND OBJECTIVE: Malnutrition is one of the causes of changes in cell metabolism. The inner ear has few energy reserves and high metabolism. The aim of this study was to analyze whether malnutrition at an early age is related to impairment of auditory processing abilities and hearing abnormalities.DESIGN AND SETTING: Retrospective cohort study conducted in a tertiary public hospital.METHODS: 45 children participated, divided as follows: G1, children diagnosed with malnutrition in their first two years of life; G2, children without history of malnutrition but with learning difficulties; G3, children without history of malnutrition and without learning difficulties. Tympanometry, pure-tone audiometry and the Staggered Spondaic Word (SSW test (auditory processing were performed. Statistical inferences were made using the Kruskal-Wallis test (α = 5% and the test of equality of proportions between two samples (α = 1.7%.RESULTS: None of the 45 children participating in this study presented hearing deficiencies. However, at six of the eight frequencies analyzed, the children in G1 presented hearing thresholds lower than those of the other groups. In the auditory processing evaluation test, it was observed that 100% of the children in G1 presented abnormal auditory processing and that G1 and G2 had similar proportions of abnormalities (P-values: G1/G2 = 0.1; G1/G3 > 0.001; G2/G3 = 0.008.CONCLUSIONS: Malnutrition at an early age caused lowering of the hearing levels, although this impairment could not be considered to be a hearing deficiency. Every child in this group presented abnormalities in auditory processing abilities.

  3. Using a staircase procedure for the objective measurement of auditory stream integration and segregation thresholds

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    Mona Isabel Spielmann

    2013-08-01

    Full Text Available Auditory scene analysis describes the ability to segregate relevant sounds out from the environment and to integrate them into a single sound stream using the characteristics of the sounds to determine whether or not they are related. This study aims to contrast task performances in objective threshold measurements of segregation and integration using identical stimuli, manipulating two variables known to influence streaming, inter-stimulus-interval (ISI and frequency difference (Δf. For each measurement, one parameter (either ISI or Δf was held constant while the other was altered in a staircase procedure. By using this paradigm, it is possible to test within-subject across multiple conditions, covering a wide Δf and ISI range in one testing session. The objective tasks were based on across-stream temporal judgments (facilitated by integration and within-stream deviance detection (facilitated by segregation. Results show the objective integration task is well suited for combination with the staircase procedure, as it yields consistent threshold measurements for separate variations of ISI and Δf, as well as being significantly related to the subjective thresholds. The objective segregation task appears less suited to the staircase procedure. With the integration-based staircase paradigm, a comprehensive assessment of streaming thresholds can be obtained in a relatively short space of time. This permits efficient threshold measurements particularly in groups for which there is little prior knowledge on the relevant parameter space for streaming perception.

  4. In-air hearing of a diving duck: A comparison of psychoacoustic and auditory brainstem response thresholds

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    Crowell, Sara E.; Wells-Berlin, Alicia M.; Therrien, Ronald E.; Yannuzzi, Sally E.; Carr, Catherine E.

    2016-01-01

    Auditory sensitivity was measured in a species of diving duck that is not often kept in captivity, the lesser scaup. Behavioral (psychoacoustics) and electrophysiological [the auditory brainstem response (ABR)] methods were used to measure in-air auditory sensitivity, and the resulting audiograms were compared. Both approaches yielded audiograms with similar U-shapes and regions of greatest sensitivity (2000−3000 Hz). However, ABR thresholds were higher than psychoacoustic thresholds at all frequencies. This difference was least at the highest frequency tested using both methods (5700 Hz) and greatest at 1000 Hz, where the ABR threshold was 26.8 dB higher than the behavioral measure of threshold. This difference is commonly reported in studies involving many different species. These results highlight the usefulness of each method, depending on the testing conditions and availability of the animals.

  5. Effect of Sound Conditioning on Click Auditory Brainstem Response Threshold Shifts in Guinea Pigs

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    Masoud Motalebi Kashani

    2012-10-01

    Full Text Available Background and Aim: Sound conditioning is exposure to a non-traumatic, moderate level of sound which increases inner ear resistance against further severe noise. In this study, we aimed to survey the effect of sound conditioning on auditory brainstem response (ABR threshold shifts using click stimulus, and the effect of the frequency of conditioning on hearing protection.Methods: Fifteen guinea pigs were randomly divided into 3 groups. Two conditioned groups were exposed to 1 kHz, and 4 kHz octave band noise at 85 dB SPL, 6 hours per day for 5 days, respectively.On the sixth day, the animals were exposed to 4 kHz octave band noise at 105 dB SPL, for 4 hours.The control group was exposed to intense noise, 4 kHz at 105 Db SPL for 4 hours (withoutconditioning. After exposure, ABR thresholds using click were recorded an hour, and 7 days after noise exposure.Results: The results of the ABR with click stimulus showed less thresold shifts in conditioned groups than control (p≤0.001. Comparison of the results of conditioned groups, showed less threshold shift by 4 kHz conditioning, however, this difference was not statistically significant (p>0.05.Conclusion: Electrophysiological data of our study showed that sound conditioning has a protective effect against subsequent intensive noise exposure, and the frequency of conditioning does not havesignificant effect on ABR threshold shifts when using click stimulus.

  6. How does the pitch and pattern of a signal affect auditory arousal thresholds?

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    Bruck, Dorothy; Ball, Michelle; Thomas, Ian; Rouillard, Vincent

    2009-06-01

    How arousal thresholds vary with different sounds is a critical issue for emergency awakenings, especially as sleepers are dying in fires despite having a working smoke alarm. Previous research shows that the current high-pitched (3000+ Hz) smoke alarm signal is significantly less effective than an alternative signal, the 520 Hz square wave, in all populations tested. However, as the number of sounds tested has been small further research is needed. Here we measured auditory arousal thresholds (AATs) across signals with a range of characteristics to determine the most effective waking signal. Thirty-nine young adults participated over three nights. In Part A, nine signals were presented in stage 4 sleep with ascending decibel levels. Signals were short beeps in the low- to mid-frequency range with different spectral complexities: square waves, pure tones, whoops and white noise. Part B manipulated temporal patterns, inserting silences of 0, 10 and 21 s after each 12 s of beeps. It was found that the low-frequency (400 and 520 Hz) square waves yielded significantly lower AATs than the alternatives. A trend was found across the three temporal manipulations, with a 10 s intervening silence showing some advantage. These findings support earlier research indicating that the best sound for awakening from deep sleep is a low-frequency square wave. It is argued that the signal with the lowest response threshold when awake may be the same as the most arousing signal when asleep, especially where the sleeper processes the signal as meaningful.

  7. Using click-evoked auditory brainstem response thresholds in infants to estimate the corresponding pure-tone audiometry thresholds in children referred from UNHS.

    Science.gov (United States)

    Lu, Tsun-Min; Wu, Fang-Wei; Chang, Hsiuwen; Lin, Hung-Ching

    2017-04-01

    To examine whether behavioral pure-tone audiometry (PTA) thresholds in children can be accurately estimated from the corresponding infants' click-evoked auditory brainstem response (ABR) thresholds through a retrospective review of data from a universal newborn hearing screening (UNHS) program in Taiwan. According to medical records from Mackay Memorial Hospital, Taipei Hospital District, 45,450 newborns received hearing screening during January 1999-December 2011. Among these newborns, 104 (82, both ears; 22, one ear; total, 186 ears) received regular follow-up and were recruited as subjects. The relationship between infant click-evoked ABR thresholds and the corresponding child PTA thresholds was determined through Pearson correlation coefficient and linear regression analyses. The correlation coefficient between click-evoked ABR thresholds and behavioral PTA thresholds at the average of frequencies of 1-4 and 2-4 kHz was 0.76 and 0.76, respectively. Linear regression analysis showed that behavioral audiometry thresholds at the average of frequencies of 1-4 and 2-4 kHz were accurately estimated from click-evoked ABR thresholds in 57% and 58% children, respectively. Click-evoked ABR testing is a reliable tool to cautiously estimate behavioral PTA thresholds at the average of frequencies of 1-4 and 2-4 kHz. For accurately performing hearing aid fitting and auditory rehabilitation in congenitally deaf infants, a combination of frequency-specific tone-burst ABR and click-evoked ABR should be used. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Effect of antioxidant supplementation on the auditory threshold in sensorineural hearing loss: a meta-analysis.

    Science.gov (United States)

    Souza, Maria Eduarda Di Cavalcanti Alves de; Costa, Klinger Vagner Teixeira da; Vitorino, Paulo Augusto; Bueno, Nassib Bezerra; Menezes, Pedro de Lemos

    2017-08-26

    Hearing loss is conceptualized as any impairment of the ability to hear and/or detect speech or environment sounds, regardless of cause, type, or degree. It may occur at different stages of life; during pregnancy or childbirth, in childhood, adulthood or old age. It should be noted that aging is the most common cause of sensorineural hearing loss followed by noise-induced hearing loss, and both are closely related to the formation of reactive oxygen species. Dietary antioxidant supplementation has been employed as a therapeutic strategy to prevent and/or delay the risks of major human diseases. To assess randomized clinical trials to determine the effect of antioxidant supplementation on the auditory thresholds in patients of different age groups with sensorineural hearing loss. This systematic review consisted of a search in the following databases: MEDLINE, CENTRAL, ScienceDirect, Scopus, Web of Science, LILACS, SciELO and ClinicalTrials.gov. Additionally, the gray literature was also searched. The search strategy included terms related to the intervention (antioxidant supplementation), primary outcome (sensorineural hearing loss), as well as terms related to randomized clinical trials to improve search sensitivity. Based on 977 potentially relevant records identified through the search in the databases, ten full-text publications were retrieved for further evaluation. The increase in threshold at the 4kHz frequency was statistically higher in the control group (1.89 [1.01-2.78], phearing loss caused by exposure to high sound pressure levels. There was no improvement in the thresholds with vitamin E supplementation. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  9. Normative auditory brainstem response data for hearing threshold and neuro-otological diagnosis in the dog.

    Science.gov (United States)

    Shiu, J N; Munro, K J; Cox, C L

    1997-03-01

    There is growing interest in the application of auditory brainstem response (ABR) audiometry for hearing assessment in dogs. The technique is far from standardised, however, resulting in large discrepancies between studies. This study aimed to obtain normative data, under clearly defined conditions, for two breeds of significantly different size; head size being a potential factor determining ABR latency values. The subjects, 20 dalmatians and 20 Jack Russell terriers, were sedated prior to ABR testing, and subcutaneous scalp electrodes used to detect the evoked potential elicited by a click stimulus presented via insert earphones. The mean ABR thresholds for the two breeds, 0 and -5 decibels re normal hearing level (dB nHL), respectively, were very similar to those for humans. The latency values of the main ABR waves and the interval between them were statistically significantly smaller for the smaller breed, but there was no correlation with head size within either breed. The results provide a baseline to assist with confirmation of hearing impairment and neuro-otological diagnosis in the dog.

  10. Assessment of hearing threshold in adults with hearing loss using an automated system of cortical auditory evoked potential detection

    Directory of Open Access Journals (Sweden)

    Alessandra Spada Durante

    Full Text Available Abstract Introduction: The use of hearing aids by individuals with hearing loss brings a better quality of life. Access to and benefit from these devices may be compromised in patients who present difficulties or limitations in traditional behavioral audiological evaluation, such as newborns and small children, individuals with auditory neuropathy spectrum, autism, and intellectual deficits, and in adults and the elderly with dementia. These populations (or individuals are unable to undergo a behavioral assessment, and generate a growing demand for objective methods to assess hearing. Cortical auditory evoked potentials have been used for decades to estimate hearing thresholds. Current technological advances have lead to the development of equipment that allows their clinical use, with features that enable greater accuracy, sensitivity, and specificity, and the possibility of automated detection, analysis, and recording of cortical responses. Objective: To determine and correlate behavioral auditory thresholds with cortical auditory thresholds obtained from an automated response analysis technique. Methods: The study included 52 adults, divided into two groups: 21 adults with moderate to severe hearing loss (study group; and 31 adults with normal hearing (control group. An automated system of detection, analysis, and recording of cortical responses (HEARLab® was used to record the behavioral and cortical thresholds. The subjects remained awake in an acoustically treated environment. Altogether, 150 tone bursts at 500, 1000, 2000, and 4000 Hz were presented through insert earphones in descending-ascending intensity. The lowest level at which the subject detected the sound stimulus was defined as the behavioral (hearing threshold (BT. The lowest level at which a cortical response was observed was defined as the cortical electrophysiological threshold. These two responses were correlated using linear regression. Results: The cortical

  11. The Comparison of the Average Thresholds of Auditory Steady-State Response in Adult Subjective Idiopathic Tinnitus and Normal Subjects

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    Zahra Ghasem Ahmad

    2009-12-01

    Full Text Available Background and Aim: Tinnitus is a common symptom among lots of people but little is known about its origins. This study was aimed at comparing the Auditory Steady-State Response (ASSR thresholds in normal cases and patients with subjective idiopathic tinnitus (SIT in order to diagnose its real origins.Materials and Methods: This case-control study was conducted on 19 patients with tinnitus and 24 normal cases aged 18-40 yr.The patients underwent broad medical tests to roll out any background reason for their tinnitus. ASSR thresholds were estimated in both groups at 20 and 40 amplitude modulation. The patients were selected from tinnitus patients in Research Center in Hazrat Rasoul Hospital, Tehran, Iran.Results: The mean ASSR thresholds at 40HZ modulation were worse in tinnitus patients compared to normal ones (p<0.05 but no significant statistical differences was detected at 20HZ. These results were found in both situations in which we averaged both ears thresholds and when we estimated the thresholds of the ears separately.Conclusion: It seems that the origin of the responses of the modulation of 40Hz, primary auditory cortex, midbrain regions and subcortical areas, in these patients is involved or the origin of their tinnitus is related to some kind of problems in these areas, although more investigation is needed about 20Hz.

  12. Broadband spectra of seismic survey air-gun emissions, with reference to dolphin auditory thresholds.

    Science.gov (United States)

    Goold, J C; Fish, P J

    1998-04-01

    Acoustic emissions from a 2120 cubic in air-gun array were recorded through a towed hydrophone assembly during an oil industry 2-D seismic survey off the West Wales Coast of the British Isles. Recorded seismic pulses were sampled, calibrated, and analyzed post-survey to investigate power levels of the pulses in the band 200 Hz-22 kHz at 750-m, 1-km, 2.2-km, and 8-km range from source. At 750-m range from source, seismic pulse power at the 200-Hz end of the spectrum was 140 dB re: 1 microPa2/Hz, and at the 20-kHz end of the spectrum seismic pulse power was 90 dB re: 1 microPa2/Hz. Although the background noise levels of the seismic recordings were far in excess of ambient, due to the proximity of engine, propeller, and flow sources of the ship towing the hydrophone, seismic power dominated the entire recorded bandwidth of 200 Hz-22 kHz at ranges of up to 2 km from the air-gun source. Even at 8-km range seismic power was still clearly in excess of the high background noise levels up to 8 kHz. Acoustic observations of common dolphins during preceding seismic surveys suggest that these animals avoided the immediate vicinity of the air-gun array while firing was in progress, i.e., localized disturbance occurred during seismic surveying. Although a general pattern of localized disturbance is suggested, one specific observation revealed that common dolphins were able to tolerate the seismic pulses at 1-km range from the air-gun array. Given the high broadband seismic pulse power levels across the entire recorded bandwidth, and known auditory thresholds for several dolphin species, we consider such seismic emissions to be clearly audible to dolphins across a bandwidth of tens on kilohertz, and at least out to 8-km range.

  13. Multiple auditory steady-state response thresholds to bone-conduction stimuli in young infants with normal hearing.

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    Small, Susan A; Stapells, David R

    2006-06-01

    Multiple auditory steady-state responses (ASSRs) probably will be incorporated into the diagnostic test battery for estimating hearing thresholds in young infants in the near future. Limiting this, however, is the fact that there are no published bone-conduction ASSR threshold data for infants with normal or impaired hearing. The objective of this study was to investigate bone-conduction ASSR thresholds in infants from a Neonatal Intensive Care Unit (NICU) and in young infants with normal hearing and to compare these with adult ASSR thresholds. ASSR thresholds to multiple bone-conduction stimuli (carrier frequencies: 500 to 4000 Hz; 77 to 101-Hz modulation rates; amplitude/frequency modulated; single-polarity stimulus) were obtained in two infant groups [N = 29 preterm (32 to 43 wk PCA), tested in NICU; N = 14 postterm (0 to 8 mo), tested in sound booth]. All infants had passed a hearing screening test. ASSR thresholds, amplitudes, and phase delays for preterm and postterm infants were compared with previously collected adult data. Mean (+/-1 SD) ASSR thresholds were 16 (11), 16 (10), 37 (10), and 33 (13) dB HL for the preterm infants and 14 (13), 2 (7), 26 (6), and 22 (8) dB HL for the postterm infants at 500, 1000, 2000, and 4000 Hz, respectively. Both infant groups had significantly better thresholds for 500 and 1000 Hz compared with 2000 and 4000 Hz, in contrast to adults who have similar thresholds across frequency (22, 26, 18, and 18 dB HL). When 500- and 1000-Hz thresholds were pooled, pre- and postterm infants had better low-frequency thresholds than adults. When 2000- and 4000-Hz thresholds were pooled, pre- and postterm infants had poorer thresholds than adults. ASSR amplitudes were significantly larger for low frequencies compared with high frequencies for both infant groups, in contrast to adults, who show little difference across frequency. ASSR phase delays were later for lower frequencies compared with higher frequencies for infants and adults

  14. Dichotic multiple-frequency auditory steady-state responses in evaluating the hearing thresholds of occupational noise-exposed workers

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    Ruey-Fen Hsu

    2011-08-01

    Full Text Available An objective, fast, and reasonably accurate assessment test that allows for easy interpretation of the responses of the hearing thresholds at all frequencies of a conventional audiogram is needed to resolve the medicolegal aspects of an occupational hearing injury. This study evaluated the use of dichotic multiple-frequency auditory steady-state responses (Mf-ASSR to predict the hearing thresholds in workers exposed to high levels of noise. The study sample included 34 workers with noise-induced hearing impairment. Thresholds of pure-tone audiometry (PTA and Mf-ASSRs at four frequencies were assessed. The differences and correlations between the thresholds of Mf-ASSRs and PTA were determined. The results showed that, on average, Mf-ASSR curves corresponded well with the thresholds of the PTA contours averaged across subjects. The Mf-ASSRs were 20±8 dB, 16±9 dB, 12±9 dB, and 11±12 dB above the thresholds of the PTA for 500 Hz, 1,000 Hz, 2,000 Hz, and 4,000 Hz, respectively. The thresholds of the PTA and the Mf-ASSRs were significantly correlated (r=0.77–0.89. We found that the measurement of Mf-ASSRs is easy and potentially time saving, provides a response at all dichotic multiple frequencies of the conventional audiogram, reduces variability in the interpretation of the responses, and correlates well with the behavioral hearing thresholds in subjects with occupational noise-induced hearing impairment. Mf-ASSR can be a valuable aid in the adjustment of compensation cases.

  15. Effects of noise exposure on neonatal auditory brainstem response thresholds in pregnant guinea pigs at different gestational periods.

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    Morimoto, Chihiro; Nario, Kazuhiko; Nishimura, Tadashi; Shimokura, Ryota; Hosoi, Hiroshi; Kitahara, Tadashi

    2017-01-01

    Noise exposure during pregnancy has been reported to cause fetal hearing impairment. However, little is known about the effects of noise exposure during various gestational stages on postnatal hearing. In the present study, we investigated the effects of noise exposure on auditory brainstem response (ABR) at the early, mid-, and late gestational periods in newborn guinea pigs. Pregnant guinea pigs were exposed to 4-kHz pure tone at a 120-dB sound pressure level for 4 h. We divided the animals into four groups as follows: the control, early gestational exposure, mid-gestational exposure, and late gestational exposure groups. ABR thresholds and latencies in newborns were recorded using 1-, 2-, and 4-kHz tone burst on postnatal days 1, 7, 14, and 28. Changes in ABR thresholds and latencies were measured between the 4 × 4 and 4 × 3 factorial groups mentioned above (gestational periods × postnatal days, gestational periods × frequencies). The thresholds were low in the order of control group exposure group exposure group and late gestational exposure group. Noise exposure during pregnancy influenced ABR thresholds in neonatal guinea pigs. This is the first study to show that noise exposure during the early, mid-, and late gestational periods significantly elevated ABR thresholds in neonatal guinea pigs. © 2016 Japan Society of Obstetrics and Gynecology.

  16. A Comparison of Thresholds in Auditory Steady - State Response with Pure Tone Audiometry in Subjects with Normal Hearing and Those with Mild and Moderate Sensorineural Hearing los

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    Sadegh Jafarzadeh

    2008-06-01

    Full Text Available Background and Aim: Among all auditory assessment tools, auditory steady state response (ASSR is a modern test. Modulation frequency for this test is usually 80 Hz. The purpose of this study, was to examined adult subjects with 40 Hz and 80 Hz ASSR and compare the results.Materials and Methods: Thirty adult (60 ears were evaluated by ASSR and PTA test, Results were divided into three groups: normal hearing, mild and moderate sensorineural hearing loss. Results: In all groups, forty hertz ASSR thresholds were relatively closer to behavioral threshold than those of 80 Hz ASSR(p<0.05. Besides, the more severe hearing loss, the lower the difference between those two thresholds. Correlation coefficients were also higher in 40 Hz ASSR(p<0.05. Conclusion: Frequency modulation thresholds with 40 Hz are more likely to be closer to the behavioral thresholds. Moreover, it has better results than the thresholds with 80 Hz.

  17. Pressure and particle motion detection thresholds in fish: a re-examination of salient auditory cues in teleosts.

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    Radford, Craig A; Montgomery, John C; Caiger, Paul; Higgs, Dennis M

    2012-10-01

    The auditory evoked potential technique has been used for the past 30 years to evaluate the hearing ability of fish. The resulting audiograms are typically presented in terms of sound pressure (dB re. 1 μPa) with the particle motion (dB re. 1 m s(-2)) component largely ignored until recently. When audiograms have been presented in terms of particle acceleration, one of two approaches has been used for stimulus characterisation: measuring the pressure gradient between two hydrophones or using accelerometers. With rare exceptions these values are presented from experiments using a speaker as the stimulus, thus making it impossible to truly separate the contribution of direct particle motion and pressure detection in the response. Here, we compared the particle acceleration and pressure auditory thresholds of three species of fish with differing hearing specialisations, goldfish (Carassius auratus, weberian ossicles), bigeye (Pempheris adspersus, ligamentous hearing specialisation) and a third species with no swim bladder, the common triplefin (Forstergyian lappillum), using three different methods of determining particle acceleration. In terms of particle acceleration, all three fish species have similar hearing thresholds, but when expressed as pressure thresholds goldfish are the most sensitive, followed by bigeye, with triplefin the least sensitive. It is suggested here that all fish have a similar ability to detect the particle motion component of the sound field and it is their ability to transduce the pressure component of the sound field to the inner ear via ancillary hearing structures that provides the differences in hearing ability. Therefore, care is needed in stimuli presentation and measurement when determining hearing ability of fish and when interpreting comparative hearing abilities between species.

  18. Prolonged response to calling songs by the L3 auditory interneuron in female crickets (Acheta domesticus): possible roles in regulating phonotactic threshold and selectiveness for call carrier frequency.

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    Bronsert, Michael; Bingol, Hilary; Atkins, Gordon; Stout, John

    2003-03-01

    L3, an auditory interneuron in the prothoracic ganglion of female crickets (Acheta domesticus) exhibited two kinds of responses to models of the male's calling song (CS): a previously described, phasically encoded immediate response; a more tonically encoded prolonged response. The onset of the prolonged response required 3-8 sec of stimulation to reach its maximum spiking rate and 6-20 sec to decay once the calling song ceased. It did not encode the syllables of the chirp. The prolonged response was sharply selective for the 4-5 kHz carrier frequency of the male's calling songs and its threshold tuning matched the threshold tuning of phonotaxis, while the immediate response of the same neuron was broadly tuned to a wide range of carrier frequencies. The thresholds for the prolonged response covaried with the changing phonotactic thresholds of 2- and 5-day-old females. Treatment of females with juvenile hormone reduced the thresholds for both phonotaxis and the prolonged response by equivalent amounts. Of the 3 types of responses to CSs provided by the ascending L1 and L3 auditory interneurons, the threshold for L3's prolonged response, on average, best matched the same females phonotactic threshold. The prolonged response was stimulated by inputs from both ears while L3's immediate response was driven only from its axon-ipsilateral ear. The prolonged response was not selective for either the CS's syllable period or chirp rate. Copyright 2003 Wiley-Liss, Inc.

  19. Stapes Vibration in the Chinchilla Middle Ear: Relation to Behavioral and Auditory-Nerve Thresholds.

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    Robles, Luis; Temchin, Andrei N; Fan, Yun-Hui; Ruggero, Mario A

    2015-08-01

    The vibratory responses to tones of the stapes and incus were measured in the middle ears of deeply anesthetized chinchillas using a wide-band acoustic-stimulus system and a laser velocimeter coupled to a microscope. With the laser beam at an angle of about 40 ° relative to the axis of stapes piston-like motion, the sensitivity-vs.-frequency curves of vibrations at the head of the stapes and the incus lenticular process were very similar to each other but larger, in the range 15-30 kHz, than the vibrations of the incus just peripheral to the pedicle. With the laser beam aligned with the axis of piston-like stapes motion, vibrations of the incus just peripheral to its pedicle were very similar to the vibrations of the lenticular process or the stapes head measured at the 40 ° angle. Thus, the pedicle prevents transmission to the stapes of components of incus vibration not aligned with the axis of stapes piston-like motion. The mean magnitude curve of stapes velocities is fairly flat over a wide frequency range, with a mean value of about 0.19 mm(.)(s Pa(-1)), has a high-frequency cutoff of 25 kHz (measured at -3 dB re the mean value), and decreases with a slope of about -60 dB/octave at higher frequencies. According to our measurements, the chinchilla middle ear transmits acoustic signals into the cochlea at frequencies exceeding both the bandwidth of responses of auditory-nerve fibers and the upper cutoff of hearing. The phase lags of stapes velocity relative to ear-canal pressure increase approximately linearly, with slopes equivalent to pure delays of about 57-76 μs.

  20. Air and Bone Conduction Click and Tone-Burst Auditory Brainstem Thresholds Using Kalman Adaptive Processing in Nonsedated Normal-Hearing Infants.

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    Elsayed, Alaaeldin M; Hunter, Lisa L; Keefe, Douglas H; Feeney, M Patrick; Brown, David K; Meinzen-Derr, Jareen K; Baroch, Kelly; Sullivan-Mahoney, Maureen; Francis, Kara; Schaid, Leigh G

    2015-01-01

    To study normative thresholds and latencies for click and tone-burst auditory brainstem response (TB-ABR) for air and bone conduction in normal infants and those discharged from neonatal intensive care units, who passed newborn hearing screening and follow-up distortion product otoacoustic emission. An evoked potential system (Vivosonic Integrity) that incorporates Bluetooth electrical isolation and Kalman-weighted adaptive processing to improve signal to noise ratios was employed for this study. Results were compared with other published data. One hundred forty-five infants who passed two-stage hearing screening with transient-evoked otoacoustic emission or automated auditory brainstem response were assessed with clicks at 70 dB nHL and threshold TB-ABR. Tone bursts at frequencies between 500 and 4000 Hz were used for air and bone conduction auditory brainstem response testing using a specified staircase threshold search to establish threshold levels and wave V peak latencies. Median air conduction hearing thresholds using TB-ABR ranged from 0 to 20 dB nHL, depending on stimulus frequency. Median bone conduction thresholds were 10 dB nHL across all frequencies, and median air-bone gaps were 0 dB across all frequencies. There was no significant threshold difference between left and right ears and no significant relationship between thresholds and hearing loss risk factors, ethnicity, or gender. Older age was related to decreased latency for air conduction. Compared with previous studies, mean air conduction thresholds were found at slightly lower (better) levels, while bone conduction levels were better at 2000 Hz and higher at 500 Hz. Latency values were longer at 500 Hz than previous studies using other instrumentation. Sleep state did not affect air or bone conduction thresholds. This study demonstrated slightly better wave V thresholds for air conduction than previous infant studies. The differences found in the present study, while statistically significant

  1. Monitoring the Hearing Handicap and the Recognition Threshold of Sentences of a Patient with Unilateral Auditory Neuropathy Spectrum Disorder with Use of a Hearing Aid.

    Science.gov (United States)

    Lima, Aline Patrícia; Mantello, Erika Barioni; Anastasio, Adriana Ribeiro Tavares

    2016-04-01

    Introduction Treatment for auditory neuropathy spectrum disorder (ANSD) is not yet well established, including the use of hearing aids (HAs). Not all patients diagnosed with ASND have access to HAs, and in some cases HAs are even contraindicated. Objective To monitor the hearing handicap and the recognition threshold of sentences in silence and in noise in a patient with ASND using an HA. Resumed Report A 47-year-old woman reported moderate sensorineural hearing loss in the right ear and high-frequency loss of 4 kHz in the left ear, with bilateral otoacoustic emissions. Auditory brainstem response suggested changes in the functioning of the auditory pathway (up to the inferior colliculus) on the right. An HA was indicated on the right. The patient was tested within a 3-month period before the HA fitting with respect to recognition threshold of sentences in quiet and in noise and for handicap determination. After HA use, she showed a 2.1-dB improvement in the recognition threshold of sentences in silence, a 6.0-dB improvement for recognition threshold of sentences in noise, and a rapid improvement of the signal-to-noise ratio from +3.66 to -2.4 dB when compared with the same tests before the fitting of the HA. Conclusion There was a reduction of the auditory handicap, although speech perception continued to be severely limited. There was a significant improvement of the recognition threshold of sentences in silence and in noise and of the signal-to-noise ratio after 3 months of HA use.

  2. Noise exposure and auditory thresholds of German airline pilots: a cross-sectional study.

    Science.gov (United States)

    Müller, Reinhard; Schneider, Joachim

    2017-05-30

    The cockpit workplace of airline pilots is a noisy environment. This study examines the hearing thresholds of pilots with respect to ambient noise and communication sound. The hearing of 487 German pilots was analysed by audiometry in the frequency range of 125 Hz-16 kHz in varying age groups. Cockpit noise (free-field) data and communication sound (acoustic manikin) measurements were evaluated. The ambient noise levels in cockpits were found to be between 74 and 80 dB(A), and the sound pressure levels under the headset were found to be between 84 and 88 dB(A).The left-right threshold differences at 3, 4 and 6 kHz show evidence of impaired hearing at the left ear, which worsens by age.In the age groups pilot group which used mostly the left ear for communication tasks (43 of 45 are in the older age group) the mean difference at 3 kHz is 6 dB, at 4 kHz 7 dB and at 6 kHz 10 dB. The pilots who used the headset only at the right ear also show worse hearing at the left ear of 2 dB at 3 kHz, 3 dB at 4 kHz and at 6 kHz. The frequency-corrected exposure levels under the headset are 7-11 dB(A) higher than the ambient noise with an averaged signal-to-noise ratio for communication of about 10 dB(A). The left ear seems to be more susceptible to hearing loss than the right ear. Active noise reduction systems allow for a reduced sound level for the communication signal below the upper exposure action value of 85 dB(A) and allow for a more relaxed working environment for pilots. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  3. Thresholds of auditory-motor coupling measured with a simple task in musicians and non-musicians: was the sound simultaneous to the key press?

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    van Vugt, Floris T; Tillmann, Barbara

    2014-01-01

    The human brain is able to predict the sensory effects of its actions. But how precise are these predictions? The present research proposes a tool to measure thresholds between a simple action (keystroke) and a resulting sound. On each trial, participants were required to press a key. Upon each keystroke, a woodblock sound was presented. In some trials, the sound came immediately with the downward keystroke; at other times, it was delayed by a varying amount of time. Participants were asked to verbally report whether the sound came immediately or was delayed. Participants' delay detection thresholds (in msec) were measured with a staircase-like procedure. We hypothesised that musicians would have a lower threshold than non-musicians. Comparing pianists and brass players, we furthermore hypothesised that, as a result of a sharper attack of the timbre of their instrument, pianists might have lower thresholds than brass players. Our results show that non-musicians exhibited higher thresholds for delay detection (180 ± 104 ms) than the two groups of musicians (102 ±65 ms), but there were no differences between pianists and brass players. The variance in delay detection thresholds could be explained by variance i n sensorimotor synchronisation capacities as well as variance in a purely auditory temporal irregularity detection measure. This suggests that the brain's capacity to generate temporal predictions of sensory consequences can be decomposed into general temporal prediction capacities together with auditory-motor coupling. These findings indicate that the brain has a relatively large window of integration within which an action and its resulting effect are judged as simultaneous. Furthermore, musical expertise may narrow this window down, potentially due to a more refined temporal prediction. This novel paradigm provides a simple test to estimate the temporal precision of auditory-motor action-effect coupling, and the paradigm can readily be incorporated in

  4. Thresholds of auditory-motor coupling measured with a simple task in musicians and non-musicians: was the sound simultaneous to the key press?

    Directory of Open Access Journals (Sweden)

    Floris T van Vugt

    Full Text Available The human brain is able to predict the sensory effects of its actions. But how precise are these predictions? The present research proposes a tool to measure thresholds between a simple action (keystroke and a resulting sound. On each trial, participants were required to press a key. Upon each keystroke, a woodblock sound was presented. In some trials, the sound came immediately with the downward keystroke; at other times, it was delayed by a varying amount of time. Participants were asked to verbally report whether the sound came immediately or was delayed. Participants' delay detection thresholds (in msec were measured with a staircase-like procedure. We hypothesised that musicians would have a lower threshold than non-musicians. Comparing pianists and brass players, we furthermore hypothesised that, as a result of a sharper attack of the timbre of their instrument, pianists might have lower thresholds than brass players. Our results show that non-musicians exhibited higher thresholds for delay detection (180 ± 104 ms than the two groups of musicians (102 ±65 ms, but there were no differences between pianists and brass players. The variance in delay detection thresholds could be explained by variance i n sensorimotor synchronisation capacities as well as variance in a purely auditory temporal irregularity detection measure. This suggests that the brain's capacity to generate temporal predictions of sensory consequences can be decomposed into general temporal prediction capacities together with auditory-motor coupling. These findings indicate that the brain has a relatively large window of integration within which an action and its resulting effect are judged as simultaneous. Furthermore, musical expertise may narrow this window down, potentially due to a more refined temporal prediction. This novel paradigm provides a simple test to estimate the temporal precision of auditory-motor action-effect coupling, and the paradigm can readily be

  5. Hearing threshold assessment in young children with electrocochleography (EcochG) and auditory brainstem responses (ABR): experience at the University Hospital of Ferrara.

    Science.gov (United States)

    Aimoni, C; Ciorba, A; Bovo, R; Trevisi, P; Busi, M; Martini, A

    2010-10-01

    Electrophysiological evaluation is a fundamental procedure for the diagnostic assessment of hearing loss during infancy; in these cases, information concerning threshold level and auditory perception is particularly useful to establish a correct hearing rehabilitation program (hearing aids and cochlear implants). Purpose of this study is to underline the role of auditory brainstem responses (ABR) and electrocochleography (EcochG) in the definition of hearing loss in a selected group of children, referred to the Audiology Department of the University Hospital of Ferrara, for a tertiary level audiological assessment. A retrospective study of the paediatric patient database at the Audiology Department of the University Hospital of Ferrara has been performed. In a period between January 2000 and December 2007, a total of 272 paediatric cases have been identified (544 ears). An EM 12 Mercury apparatus has been used for the electrophysiological threshold identification (ABR and EcochG). Recordings were carried out under general anaesthesia, in a protected enviroment. In 19 of the 272 paediatric cases selected--38 ears (7%), the results of threshold evaluation through ABR were uncertain. The Ecochg recording resulted crucial for the final diagnosis in terms of definition of the hearing threshold level, and it was then possible to ensure the better hearing rehabilitation strategy. ABR has to be considered the first choice in hearing assessment strategy, either for screening or for diagnosis in newborns as well as in non-collaborating children; ECochG still may be considered a reliable diagnostic tool. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  6. Fast Hearing-Threshold Estimation Using Multiple Auditory Steady-State Responses with Narrow-Band Chirps and Adaptive Stimulus Patterns

    Directory of Open Access Journals (Sweden)

    Roland Mühler

    2012-01-01

    Full Text Available This paper describes the estimation of hearing thresholds in normal-hearing and hearing-impaired subjects on the basis of multiple-frequency auditory steady-state responses (ASSRs. The ASSR was measured using two new techniques: (i adaptive stimulus patterns and (ii narrow-band chirp stimuli. ASSR thresholds in 16 normal-hearing and 16 hearing-impaired adults were obtained simultaneously at both ears at 500, 1000, 2000, and 4000?Hz, using a multiple-frequency stimulus built up of four one-octave-wide narrow-band chirps with a repetition rate of 40?Hz. A statistical test in the frequency domain was used to detect the response. The recording of the steady-state responses was controlled in eight independent recording channels with an adaptive, semiautomatic algorithm. The average differences between the behavioural hearing thresholds and the ASSR threshold estimate were 10, 8, 13, and 15?dB for test frequencies of 500, 1000, 2000, and 4000?Hz, respectively. The average overall test duration of 18.6 minutes for the threshold estimations at the four frequencies and both ears demonstrates the benefit of an adaptive recording algorithm and the efficiency of optimised narrow-band chirp stimuli.

  7. Effects of N-Acetylcysteine on Auditory Brainstem Response Threshold Shift in Rabbits Exposed to Noise and Carbon Monoxide

    OpenAIRE

    Seyedbagher Mortazavi; Masoud M. Kashani; Ali Khavanin; Abdolamir Alameh; Ramezan Mirzaee; Mehdi Akbari

    2010-01-01

    Problem statement: Noise Induced Hearing Loss (NIHL) is one of the most important occupational disease in worldwide. NIHL has been found to be potentiated by simultaneous Carbon monoxide (CO) exposure. Exposure to noise plus CO is common in occupational and environmental settings. Free radicals have been implicated in cochlear damage resulting from exposure to noise and due to CO hypoxia This study examined whether N-Acetylcysteine (NAC) administration cause attenuation of Auditory Brainstem ...

  8. Measurement of implant stability and auditory pure-tone thresholds of Baha patients comparing osteosysthesis and osseointegrated systems.

    Science.gov (United States)

    Rahne, Torsten; Götze, Gerrit; Pein, M Katharina

    2015-03-01

    With bone-anchored hearing systems the implant-bone junction is critical for the transmission of mechanical vibrations to the skull. The implant stability might differ between available and widely applied implants and can be estimated by resonance frequency analysis. The implant stability and the audiological performance of ten adult long-time users where a bone-anchored hearing system was connected by an Baha osseointegrated implant (Cochlear Ltd, Mölnlycke, Sweden) were compared with the implant stability of fourteen adult patients provided with a Ti-epiplating osteosysthesis system (Medicon, Tuttlingen, Germany). The acute implant stability was compared between these two implants with one cadaveric skull. The results show higher resonance frequencies and thus higher implant stability for the osseointegrating system of both, measuring acute and after long-time use of the implants. The audiological outcomes show frequency dependent differences between both systems as determined by comparing pure-tone bone-conduction audiometry. However, measuring thresholds by a direct stimulation of the implant reveals better hearing with low frequencies for the osseointegrated system and for high frequencies with the osteosysthesis system. At all, the implant selection has an impact on the implant stability and on the pure-tone hearing. Copyright © 2014. Published by Elsevier GmbH.

  9. Sub-threshold cross-modal sensory interaction in the thalamus: lemniscal auditory response in the medial geniculate nucleus is modulated by somatosensory stimulation.

    Science.gov (United States)

    Donishi, T; Kimura, A; Imbe, H; Yokoi, I; Kaneoke, Y

    2011-02-03

    Recent studies have highlighted cross-modal sensory modulations in the primary sensory areas in the cortex, suggesting that cross-modal sensory interactions occur at early stages in the hierarchy of sensory processing. Multi-modal sensory inputs from non-lemniscal thalamic nuclei and cortical inputs from the secondary sensory and association areas are considered responsible for the modulations. On the other hand, there is little evidence of cross-sensory modal sensitivities in lemniscal thalamic nuclei. In the present study, we were interested in a possibility that somatosensory stimulation may affect auditory response in the ventral division (MGV) of the medial geniculate nucleus (MG), a lemniscal thalamic nucleus that is considered to be dedicated to auditory uni-modal processing. Experiments were performed on anesthetized rats. Transcutaneous electrical stimulation of the hindpaw, which is thought to evoke nociception and seems unrelated to auditory processing, modulated unit discharges in response to auditory stimulation (noise bursts). The modulation was observed in the MGV and non-lemniscal auditory thalamic nuclei such as the dorsal and medial divisions of the MG. The major effect of somatosensory stimulation was suppression. The most robust suppression was induced by electrical stimuli given simultaneously with noise bursts or preceding noise bursts by 10 to 20 ms. The results indicate that the lemniscal (MGV) and non-lemniscal auditory nuclei are subject to somatosensory influence. In everyday experience intense somatosensory stimuli such as pain interrupt our ongoing hearing or interfere with clear recognition of sound. The modulation of lemniscal auditory response by somatosensory stimulation may underlie such cross-modal disturbance of auditory perception as a form of cross-modal switching of attention. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Acoustic Reflexes in Normal-Hearing Adults, Typically Developing Children, and Children with Suspected Auditory Processing Disorder: Thresholds, Real-Ear Corrections, and the Role of Static Compliance on Estimates.

    Science.gov (United States)

    Saxena, Udit; Allan, Chris; Allen, Prudence

    2017-06-01

    Previous studies have suggested elevated reflex thresholds in children with auditory processing disorders (APDs). However, some aspects of the child's ear such as ear canal volume and static compliance of the middle ear could possibly affect the measurements of reflex thresholds and thus impact its interpretation. Sound levels used to elicit reflexes in a child's ear may be higher than predicted by calibration in a standard 2-cc coupler, and lower static compliance could make visualization of very small changes in impedance at threshold difficult. For this purpose, it is important to evaluate threshold data with consideration of differences between children and adults. A set of studies were conducted. The first compared reflex thresholds obtained using standard clinical procedures in children with suspected APD to that of typically developing children and adults to test the replicability of previous studies. The second study examined the impact of ear canal volume on estimates of reflex thresholds by applying real-ear corrections. Lastly, the relationship between static compliance and reflex threshold estimates was explored. The research is a set of case-control studies with a repeated measures design. The first study included data from 20 normal-hearing adults, 28 typically developing children, and 66 children suspected of having an APD. The second study included 28 normal-hearing adults and 30 typically developing children. In the first study, crossed and uncrossed reflex thresholds were measured in 5-dB step size. Reflex thresholds were analyzed using repeated measures analysis of variance (RM-ANOVA). In the second study, uncrossed reflex thresholds, real-ear correction, ear canal volume, and static compliance were measured. Reflex thresholds were measured using a 1-dB step size. The effect of real-ear correction and static compliance on reflex threshold was examined using RM-ANOVA and Pearson correlation coefficient, respectively. Study 1 replicated previous

  11. Auditory Display

    DEFF Research Database (Denmark)

    volume. The conference's topics include auditory exploration of data via sonification and audification; real time monitoring of multivariate date; sound in immersive interfaces and teleoperation; perceptual issues in auditory display; sound in generalized computer interfaces; technologies supporting...... auditory display creation; data handling for auditory display systems; applications of auditory display....

  12. Medidas operantes de limiar auditivo em crianças com surdez pré-lingual, usuárias de implante coclear Operant measures of auditory threshold in prelingually deaf children with cochlear implant

    Directory of Open Access Journals (Sweden)

    Wagner R. da Silva

    2011-01-01

    Full Text Available Limiares auditivos de crianças surdas pré-linguais usuárias de implante coclear foram avaliados com estimulação elétrica em um dos eletrodos mediais. A avaliação empregou um procedimento operante do tipo go/no go para ensinar uma discriminação simples, evidenciada por uma resposta motora, entre presença e ausência do estímulo auditivo. Estabelecida a linha de base, a manipulação na intensidade do estímulo foi implementada de acordo com o método psicofísico de escada modificado, começando por uma seqüência descendente. Os sete participantes do estudo mostraram perda da precisão no responder sob controle do estímulo quando a intensidade diminuía além de um certo valor e a precisão era recuperada quando a intensidade era novamente aumentada, o que permitiu a identificação de limiares individuais. Os resultados sugerem que o método psicofísico combinado com o procedimento operante pode ser uma alternativa viável para avaliar limiar auditivo de pessoas sem linguagem em situação clínica de regulagem do implante coclear.Auditory thresholds of prelingually deaf children who received cochlear implants were evaluated for the electrical stimulation to one of the medial electrodes. A go/no go operant procedure was used to teach a simple discrimination, indicated by a motor response, between the presence versus the absence of an auditory stimulus. Simple discrimination was used as a baseline upon which the electrical stimulus's intensity was manipulated in a decreasing sequence followed by an increasing sequence, according to a modified psychophysical staircase method. The accuracy of responding in the presence of the electrical stimulus was reduced for all seven participants when the stimulus intensity decreased bellow a certain value and was recovered when the stimulus intensity was increased to the previous level. The experimental design allowed reliable identification of individual thresholds. The results suggest that

  13. Effects of Age and Degree of Hearing Loss on the Agreement and Correlation Between Sound Field Audiometric Thresholds and Tone Burst Auditory Brainstem Response Thresholds in Infants and Young Children

    Directory of Open Access Journals (Sweden)

    Chung-Yi Lee

    2008-11-01

    Conclusion: The evoked-potentials test, properly obtained and interpreted with respect to the effects of age and degree of hearing loss, may provide a very informative hearing threshold reference to help in behavioral audiometric evaluation in infants and young children with hearing loss.

  14. Correlation between maximum phonetically balanced word recognition score and pure-tone auditory threshold in elder presbycusis patients over 80 years old.

    Science.gov (United States)

    Deng, Xin-Sheng; Ji, Fei; Yang, Shi-Ming

    2014-02-01

    The maximum phonetically balanced word recognition score (PBmax) showed poor correlation with pure-tone thresholds in presbycusis patients older than 80 years. To study the characteristics of monosyllable recognition in presbycusis patients older than 80 years of age. Thirty presbycusis patients older than 80 years were included as the test group (group 80+). Another 30 patients aged 60-80 years were selected as the control group (group 80-) . PBmax was tested by Mandarin monosyllable recognition test materials with the signal level at 30 dB above the averaged thresholds of 0.5, 1, 2, and 4 kHz (4FA) or the maximum comfortable level. The PBmax values of the test group and control group were compared with each other and the correlation between PBmax and predicted maximum speech recognition scores based on 4FA (PBmax-predict) were statistically analyzed. Under the optimal test conditions, the averaged PBmax was (77.3 ± 16.7) % for group 80- and (52.0 ± 25.4) % for group 80+ (p < 0.001). The PBmax of group 80- was significantly correlated with PBmax-predict (Spearman correlation = 0.715, p < 0.001). The score for group 80+ was less statistically correlated with PBmax-predict (Spearman correlation = 0.572, p = 0.001).

  15. Auditory agnosia.

    Science.gov (United States)

    Slevc, L Robert; Shell, Alison R

    2015-01-01

    Auditory agnosia refers to impairments in sound perception and identification despite intact hearing, cognitive functioning, and language abilities (reading, writing, and speaking). Auditory agnosia can be general, affecting all types of sound perception, or can be (relatively) specific to a particular domain. Verbal auditory agnosia (also known as (pure) word deafness) refers to deficits specific to speech processing, environmental sound agnosia refers to difficulties confined to non-speech environmental sounds, and amusia refers to deficits confined to music. These deficits can be apperceptive, affecting basic perceptual processes, or associative, affecting the relation of a perceived auditory object to its meaning. This chapter discusses what is known about the behavioral symptoms and lesion correlates of these different types of auditory agnosia (focusing especially on verbal auditory agnosia), evidence for the role of a rapid temporal processing deficit in some aspects of auditory agnosia, and the few attempts to treat the perceptual deficits associated with auditory agnosia. A clear picture of auditory agnosia has been slow to emerge, hampered by the considerable heterogeneity in behavioral deficits, associated brain damage, and variable assessments across cases. Despite this lack of clarity, these striking deficits in complex sound processing continue to inform our understanding of auditory perception and cognition. © 2015 Elsevier B.V. All rights reserved.

  16. Tactile feedback improves auditory spatial localization.

    Science.gov (United States)

    Gori, Monica; Vercillo, Tiziana; Sandini, Giulio; Burr, David

    2014-01-01

    Our recent studies suggest that congenitally blind adults have severely impaired thresholds in an auditory spatial bisection task, pointing to the importance of vision in constructing complex auditory spatial maps (Gori et al., 2014). To explore strategies that may improve the auditory spatial sense in visually impaired people, we investigated the impact of tactile feedback on spatial auditory localization in 48 blindfolded sighted subjects. We measured auditory spatial bisection thresholds before and after training, either with tactile feedback, verbal feedback, or no feedback. Audio thresholds were first measured with a spatial bisection task: subjects judged whether the second sound of a three sound sequence was spatially closer to the first or the third sound. The tactile feedback group underwent two audio-tactile feedback sessions of 100 trials, where each auditory trial was followed by the same spatial sequence played on the subject's forearm; auditory spatial bisection thresholds were evaluated after each session. In the verbal feedback condition, the positions of the sounds were verbally reported to the subject after each feedback trial. The no feedback group did the same sequence of trials, with no feedback. Performance improved significantly only after audio-tactile feedback. The results suggest that direct tactile feedback interacts with the auditory spatial localization system, possibly by a process of cross-sensory recalibration. Control tests with the subject rotated suggested that this effect occurs only when the tactile and acoustic sequences are spatially congruent. Our results suggest that the tactile system can be used to recalibrate the auditory sense of space. These results encourage the possibility of designing rehabilitation programs to help blind persons establish a robust auditory sense of space, through training with the tactile modality.

  17. Auditory Impairment in Young Type 1 Diabetics.

    Science.gov (United States)

    Hou, Yanlian; Xiao, Xiaoyan; Ren, Jianmin; Wang, Yajuan; Zhao, Faming

    2015-10-01

    More attention has recently been focused on auditory impairment of young type 1 diabetics. This study aimed to evaluate auditory function of young type 1 diabetics and the correlation between clinical indexes and hearing impairment. We evaluated the auditory function of 50 type 1 diabetics and 50 healthy subjects. Clinical indexes were measured along with analyzing their relation of auditory function. Type 1 diabetic patients demonstrated a deficit with elevated thresholds at right ear and left ear when compared to healthy controls (p p V and interwave I-V) and left ear (wave III, V and interwave I-III, I-V) in diabetic group significantly increased compared to those in control subjects (p p p p p <0.01). Type 1 diabetics exerted higher auditory threshold, slower auditory conduction time and cochlear impairment. HDL-cholesterol, diabetes duration, systemic blood pressure, microalbuminuria, GHbA1C, triglyceride, and age may affect the auditory function of type 1 diabetics. Copyright © 2015 IMSS. Published by Elsevier Inc. All rights reserved.

  18. Sensitivity and specificity of auditory steady-state response testing

    Directory of Open Access Journals (Sweden)

    Camila Maia Rabelo

    2011-01-01

    Full Text Available INTRODUCTION: The ASSR test is an electrophysiological test that evaluates, among other aspects, neural synchrony, based on the frequency or amplitude modulation of tones. OBJECTIVE: The aim of this study was to determine the sensitivity and specificity of auditory steady-state response testing in detecting lesions and dysfunctions of the central auditory nervous system. METHODS: Seventy volunteers were divided into three groups: those with normal hearing; those with mesial temporal sclerosis; and those with central auditory processing disorder. All subjects underwent auditory steady-state response testing of both ears at 500 Hz and 2000 Hz (frequency modulation, 46 Hz. The difference between auditory steady-state response-estimated thresholds and behavioral thresholds (audiometric evaluation was calculated. RESULTS: Estimated thresholds were significantly higher in the mesial temporal sclerosis group than in the normal and central auditory processing disorder groups. In addition, the difference between auditory steady-state response-estimated and behavioral thresholds was greatest in the mesial temporal sclerosis group when compared to the normal group than in the central auditory processing disorder group compared to the normal group. DISCUSSION: Research focusing on central auditory nervous system (CANS lesions has shown that individuals with CANS lesions present a greater difference between ASSR-estimated thresholds and actual behavioral thresholds; ASSR-estimated thresholds being significantly worse than behavioral thresholds in subjects with CANS insults. This is most likely because the disorder prevents the transmission of the sound stimulus from being in phase with the received stimulus, resulting in asynchronous transmitter release. Another possible cause of the greater difference between the ASSR-estimated thresholds and the behavioral thresholds is impaired temporal resolution. CONCLUSIONS: The overall sensitivity of auditory steady

  19. [Auditory fatigue].

    Science.gov (United States)

    Sanjuán Juaristi, Julio; Sanjuán Martínez-Conde, Mar

    2015-01-01

    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. 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. 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. 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. Copyright © 2013 Elsevier España, S.L.U. y Sociedad Española de Otorrinolaringología y Patología Cérvico-Facial. All rights reserved.

  20. Estimating auditory filter bandwidth using distortion product otoacoustic emissions

    DEFF Research Database (Denmark)

    Rukjær, Andreas Harbo; Hauen, Sigurd van; Ordoñez Pizarro, Rodrigo Eduardo

    2017-01-01

    The basic frequency selectivity in the listener’s hearing is often characterized by auditory filters. These filters are determined through listening tests, which estimate the masking threshold as a function of frequency of the tone and the bandwidth of the masking sound. The auditory filters have...... at 1, 2, and 4 kHz for 10 young normal-hearing subjects....

  1. Early Visual Deprivation Severely Compromises the Auditory Sense of Space in Congenitally Blind Children

    Science.gov (United States)

    Vercillo, Tiziana; Burr, David; Gori, Monica

    2016-01-01

    A recent study has shown that congenitally blind adults, who have never had visual experience, are impaired on an auditory spatial bisection task (Gori, Sandini, Martinoli, & Burr, 2014). In this study we investigated how thresholds for auditory spatial bisection and auditory discrimination develop with age in sighted and congenitally blind…

  2. Auditory Hallucination

    Directory of Open Access Journals (Sweden)

    MohammadReza Rajabi

    2003-09-01

    Full Text Available Auditory Hallucination or Paracusia is a form of hallucination that involves perceiving sounds without auditory stimulus. A common is hearing one or more talking voices which is associated with psychotic disorders such as schizophrenia or mania. Hallucination, itself, is the most common feature of perceiving the wrong stimulus or to the better word perception of the absence stimulus. Here we will discuss four definitions of hallucinations:1.Perceiving of a stimulus without the presence of any subject; 2. hallucination proper which are the wrong perceptions that are not the falsification of real perception, Although manifest as a new subject and happen along with and synchronously with a real perception;3. hallucination is an out-of-body perception which has no accordance with a real subjectIn a stricter sense, hallucinations are defined as perceptions in a conscious and awake state in the absence of external stimuli which have qualities of real perception, in that they are vivid, substantial, and located in external objective space. We are going to discuss it in details here.

  3. Facilitated auditory detection for speech sounds

    Directory of Open Access Journals (Sweden)

    Carine eSignoret

    2011-07-01

    Full Text Available If it is well known that knowledge facilitates higher cognitive functions, such as visual and auditory word recognition, little is known about the influence of knowledge on detection, particularly in the auditory modality. Our study tested the influence of phonological and lexical knowledge on auditory detection. Words, pseudo words and complex non phonological sounds, energetically matched as closely as possible, were presented at a range of presentation levels from sub threshold to clearly audible. The participants performed a detection task (Experiments 1 and 2 that was followed by a two alternative forced choice recognition task in Experiment 2. The results of this second task in Experiment 2 suggest a correct recognition of words in the absence of detection with a subjective threshold approach. In the detection task of both experiments, phonological stimuli (words and pseudo words were better detected than non phonological stimuli (complex sounds, presented close to the auditory threshold. This finding suggests an advantage of speech for signal detection. An additional advantage of words over pseudo words was observed in Experiment 2, suggesting that lexical knowledge could also improve auditory detection when listeners had to recognize the stimulus in a subsequent task. Two simulations of detection performance performed on the sound signals confirmed that the advantage of speech over non speech processing could not be attributed to energetic differences in the stimuli.

  4. Presbycusis and auditory brainstem responses: a review

    Directory of Open Access Journals (Sweden)

    Shilpa Khullar

    2011-06-01

    Full Text Available Age-related hearing loss or presbycusis is a complex phenomenon consisting of elevation of hearing levels as well as changes in the auditory processing. It is commonly classified into four categories depending on the cause. Auditory brainstem responses (ABRs are a type of early evoked potentials recorded within the first 10 ms of stimulation. They represent the synchronized activity of the auditory nerve and the brainstem. Some of the changes that occur in the aging auditory system may significantly influence the interpretation of the ABRs in comparison with the ABRs of the young adults. The waves of ABRs are described in terms of amplitude, latencies and interpeak latency of the different waves. There is a tendency of the amplitude to decrease and the absolute latencies to increase with advancing age but these trends are not always clear due to increase in threshold with advancing age that act a major confounding factor in the interpretation of ABRs.

  5. Across frequency processes involved in auditory detection of coloration

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Kerketsos, P

    2008-01-01

    filterbank was designed to approximate auditory filter-shapes measured by Oxenham and Shera [JARO, 2003, 541-554], derived from forward masking data. The results of the present study demonstrate that a “purely” spectrum-based model approach can successfully describe auditory coloration detection even at high...... detection are investigated. Coloration detection thresholds were therefore measured as a function of reflection delay and stimulus bandwidth. In order to investigate the involved auditory mechanisms, an auditory model was employed that was conceptually similar to the peripheral weighting model [Yost, JASA...

  6. Enhanced auditory temporal gap detection in listeners with musical training.

    Science.gov (United States)

    Mishra, Srikanta K; Panda, Manas R; Herbert, Carolyn

    2014-08-01

    Many features of auditory perception are positively altered in musicians. Traditionally auditory mechanisms in musicians are investigated using the Western-classical musician model. The objective of the present study was to adopt an alternative model-Indian-classical music-to further investigate auditory temporal processing in musicians. This study presents that musicians have significantly lower across-channel gap detection thresholds compared to nonmusicians. Use of the South Indian musician model provides an increased external validity for the prediction, from studies on Western-classical musicians, that auditory temporal coding is enhanced in musicians.

  7. Auditory capture of visual motion: effects on perception and discrimination.

    Science.gov (United States)

    McCourt, Mark E; Leone, Lynnette M

    2016-09-28

    We asked whether the perceived direction of visual motion and contrast thresholds for motion discrimination are influenced by the concurrent motion of an auditory sound source. Visual motion stimuli were counterphasing Gabor patches, whose net motion energy was manipulated by adjusting the contrast of the leftward-moving and rightward-moving components. The presentation of these visual stimuli was paired with the simultaneous presentation of auditory stimuli, whose apparent motion in 3D auditory space (rightward, leftward, static, no sound) was manipulated using interaural time and intensity differences, and Doppler cues. In experiment 1, observers judged whether the Gabor visual stimulus appeared to move rightward or leftward. In experiment 2, contrast discrimination thresholds for detecting the interval containing unequal (rightward or leftward) visual motion energy were obtained under the same auditory conditions. Experiment 1 showed that the perceived direction of ambiguous visual motion is powerfully influenced by concurrent auditory motion, such that auditory motion 'captured' ambiguous visual motion. Experiment 2 showed that this interaction occurs at a sensory stage of processing as visual contrast discrimination thresholds (a criterion-free measure of sensitivity) were significantly elevated when paired with congruent auditory motion. These results suggest that auditory and visual motion signals are integrated and combined into a supramodal (audiovisual) representation of motion.

  8. Upper limits of auditory rotational motion perception.

    Science.gov (United States)

    Féron, François-Xavier; Frissen, Ilja; Boissinot, Julien; Guastavino, Catherine

    2010-12-01

    Three experiments are reported, which investigated the auditory velocity thresholds beyond which listeners are no longer able to perceptually resolve a smooth circular trajectory. These thresholds were measured for band-limited noises, white noise, and harmonic sounds (HS), and in different acoustical environments. Experiments 1 and 2 were conducted in an acoustically dry laboratory. Observed thresholds varied as a function of stimulus type and spectral content. Thresholds for band-limited noises were unaffected by center frequency and equal to that of white noise. For HS, however, thresholds decreased as the fundamental frequency of the stimulus increased. The third experiment was a replication of the second in a reverberant concert hall, which produced qualitatively similar results except that thresholds were significantly higher than in the acoustically dry laboratory.

  9. [Verbal auditory agnosia: SPECT study of the brain].

    Science.gov (United States)

    Carmona, C; Casado, I; Fernández-Rojas, J; Garín, J; Rayo, J I

    1995-01-01

    Verbal auditory agnosia are rare in clinical practice. Clinically, it characterized by impairment of comprehension and repetition of speech but reading, writing, and spontaneous speech are preserved. So it is distinguished from generalized auditory agnosia by the preserved ability to recognize non verbal sounds. We present the clinical picture of a forty-years-old, right handed woman who developed verbal auditory agnosic after an bilateral temporal ischemic infarcts due to atrial fibrillation by dilated cardiomyopathie. Neurophysiological studies by pure tone threshold audiometry: brainstem auditory evoked potentials and cortical auditory evoked potentials showed sparing of peripheral hearing and intact auditory pathway in brainstem but impaired cortical responses. Cranial CT-SCAN revealed two large hypodenses area involving both cortico-subcortical temporal lobes. Cerebral SPECT using 99mTc-HMPAO as radiotracer showed hypoperfusion just posterior in both frontal lobes nect to Roland's fissure and at level of bitemporal lobes just anterior to Sylvian's fissure.

  10. Cigarette smoking as a risk factor for auditory problems.

    Science.gov (United States)

    Paschoal, Carolina Pamplona; Azevedo, Marisa Frasson de

    2009-01-01

    Smoking is a public health concern and we are still unsure of its relation with auditory problems. To study the effects of cigarette smoking in auditory thresholds, in otoacoustic emissions and in their inhibition by the efferent olivocochlear medial system. 144 adults from both genders, between 20 and 31 years of age, smoking and non-smoking individuals were submitted to conventional and high-frequency audiometry, transient stimuli otoacoustic emissions and suppression effect investigation. smokers presented worse auditory thresholds in the frequencies of 12.500Hz in the right ear and 14,000 kHz in both ears. Regarding the otoacoustic emissions, smokers group presented a lower response level in the frequencies of 1,000Hz in both ears and 4,000Hz in the left ear. Among smokers there were more cases of cochlear dysfunction and tinnitus. Our results suggest that cigarette smoking has an adverse effect on the auditory system.

  11. Neurophysiological investigation of idiopathic acquired auditory-visual synesthesia.

    Science.gov (United States)

    Afra, Pegah; Anderson, Jeffrey; Funke, Michael; Johnson, Michael; Matsuo, Fumisuke; Constantino, Tawnya; Warner, Judith

    2012-01-01

    We present a case of acquired auditory-visual synesthesia and its neurophysiological investigation in a healthy 42-year-old woman. She started experiencing persistent positive and intermittent negative visual phenomena at age 37 followed by auditory-visual synesthesia. Her neurophysiological investigation included video-EEG, fMRI, and MEG. Auditory stimuli (700 Hz, 50 ms duration, 0.5 s ISI) were presented binaurally at 60 db above the hearing threshold in a dark room. The patient had bilateral symmetrical auditory-evoked neuromagnetic responses followed by an occipital-evoked field 16.3 ms later. The activation of occipital cortex following auditory stimuli may represent recruitment of existing cross-modal sensory pathways.

  12. Auditory and cognitive performance in elderly musicians and nonmusicians.

    Directory of Open Access Journals (Sweden)

    Massimo Grassi

    Full Text Available Musicians represent a model for examining brain and behavioral plasticity in terms of cognitive and auditory profile, but few studies have investigated whether elderly musicians have better auditory and cognitive abilities than nonmusicians. The aim of the present study was to examine whether being a professional musician attenuates the normal age-related changes in hearing and cognition. Elderly musicians still active in their profession were compared with nonmusicians on auditory performance (absolute threshold, frequency intensity, duration and spectral shape discrimination, gap and sinusoidal amplitude-modulation detection, and on simple (short-term memory and more complex and higher-order (working memory [WM] and visuospatial abilities cognitive tasks. The sample consisted of adults at least 65 years of age. The results showed that older musicians had similar absolute thresholds but better supra-threshold discrimination abilities than nonmusicians in four of the six auditory tasks administered. They also had a better WM performance, and stronger visuospatial abilities than nonmusicians. No differences were found between the two groups' short-term memory. Frequency discrimination and gap detection for the auditory measures, and WM complex span tasks and one of the visuospatial tasks for the cognitive ones proved to be very good classifiers of the musicians. These findings suggest that life-long music training may be associated with enhanced auditory and cognitive performance, including complex cognitive skills, in advanced age. However, whether this music training represents a protective factor or not needs further investigation.

  13. Auditory and cognitive performance in elderly musicians and nonmusicians.

    Science.gov (United States)

    Grassi, Massimo; Meneghetti, Chiara; Toffalini, Enrico; Borella, Erika

    2017-01-01

    Musicians represent a model for examining brain and behavioral plasticity in terms of cognitive and auditory profile, but few studies have investigated whether elderly musicians have better auditory and cognitive abilities than nonmusicians. The aim of the present study was to examine whether being a professional musician attenuates the normal age-related changes in hearing and cognition. Elderly musicians still active in their profession were compared with nonmusicians on auditory performance (absolute threshold, frequency intensity, duration and spectral shape discrimination, gap and sinusoidal amplitude-modulation detection), and on simple (short-term memory) and more complex and higher-order (working memory [WM] and visuospatial abilities) cognitive tasks. The sample consisted of adults at least 65 years of age. The results showed that older musicians had similar absolute thresholds but better supra-threshold discrimination abilities than nonmusicians in four of the six auditory tasks administered. They also had a better WM performance, and stronger visuospatial abilities than nonmusicians. No differences were found between the two groups' short-term memory. Frequency discrimination and gap detection for the auditory measures, and WM complex span tasks and one of the visuospatial tasks for the cognitive ones proved to be very good classifiers of the musicians. These findings suggest that life-long music training may be associated with enhanced auditory and cognitive performance, including complex cognitive skills, in advanced age. However, whether this music training represents a protective factor or not needs further investigation.

  14. A Time-Frequency Auditory Model Using Wavelet Packets

    DEFF Research Database (Denmark)

    Agerkvist, Finn

    1996-01-01

    A time-frequency auditory model is presented. The model uses the wavelet packet analysis as the preprocessor. The auditory filters are modelled by the rounded exponential filters, and the excitation is smoothed by a window function. By comparing time-frequency excitation patterns it is shown...... that the change in the time-frequency excitation pattern introduced when a test tone at masked threshold is added to the masker is approximately equal to 7 dB for all types of maskers. The classic detection ratio therefore overrates the detection efficiency of the auditory system....

  15. Effect of conductive hearing loss on central auditory function

    Directory of Open Access Journals (Sweden)

    Arash Bayat

    Full Text Available Abstract Introduction: It has been demonstrated that long-term Conductive Hearing Loss (CHL may influence the precise detection of the temporal features of acoustic signals or Auditory Temporal Processing (ATP. It can be argued that ATP may be the underlying component of many central auditory processing capabilities such as speech comprehension or sound localization. Little is known about the consequences of CHL on temporal aspects of central auditory processing. Objective: This study was designed to assess auditory temporal processing ability in individuals with chronic CHL. Methods: During this analytical cross-sectional study, 52 patients with mild to moderate chronic CHL and 52 normal-hearing listeners (control, aged between 18 and 45 year-old, were recruited. In order to evaluate auditory temporal processing, the Gaps-in-Noise (GIN test was used. The results obtained for each ear were analyzed based on the gap perception threshold and the percentage of correct responses. Results: The average of GIN thresholds was significantly smaller for the control group than for the CHL group for both ears (right: p = 0.004; left: p 0.05. Conclusion: The results suggest reduced auditory temporal processing ability in adults with CHL compared to normal hearing subjects. Therefore, developing a clinical protocol to evaluate auditory temporal processing in this population is recommended.

  16. BAER - brainstem auditory evoked response

    Science.gov (United States)

    ... auditory potentials; Brainstem auditory evoked potentials; Evoked response audiometry; Auditory brainstem response; ABR; BAEP ... Normal results vary. Results will depend on the person and the instruments used to perform the test.

  17. Auditory Processing Disorder (For Parents)

    Science.gov (United States)

    ... role. Auditory cohesion problems: This is when higher-level listening tasks are difficult. Auditory cohesion skills — drawing inferences from conversations, understanding riddles, or comprehending verbal math problems — require heightened auditory processing and language levels. ...

  18. The effects of speech motor preparation on auditory perception

    Science.gov (United States)

    Myers, John

    Perception and action are coupled via bidirectional relationships between sensory and motor systems. Motor systems influence sensory areas by imparting a feedforward influence on sensory processing termed "motor efference copy" (MEC). MEC is suggested to occur in humans because speech preparation and production modulate neural measures of auditory cortical activity. However, it is not known if MEC can affect auditory perception. We tested the hypothesis that during speech preparation auditory thresholds will increase relative to a control condition, and that the increase would be most evident for frequencies that match the upcoming vocal response. Participants performed trials in a speech condition that contained a visual cue indicating a vocal response to prepare (one of two frequencies), followed by a go signal to speak. To determine threshold shifts, voice-matched or -mismatched pure tones were presented at one of three time points between the cue and target. The control condition was the same except the visual cues did not specify a response and subjects did not speak. For each participant, we measured f0 thresholds in isolation from the task in order to establish baselines. Results indicated that auditory thresholds were highest during speech preparation, relative to baselines and a non-speech control condition, especially at suprathreshold levels. Thresholds for tones that matched the frequency of planned responses gradually increased over time, but sharply declined for the mismatched tones shortly before targets. Findings support the hypothesis that MEC influences auditory perception by modulating thresholds during speech preparation, with some specificity relative to the planned response. The threshold increase in tasks vs. baseline may reflect attentional demands of the tasks.

  19. Resizing Auditory Communities

    DEFF Research Database (Denmark)

    Kreutzfeldt, Jacob

    2012-01-01

    Heard through the ears of the Canadian composer and music teacher R. Murray Schafer the ideal auditory community had the shape of a village. Schafer’s work with the World Soundscape Project in the 70s represent an attempt to interpret contemporary environments through musical and auditory...

  20. Methodology and apparatus for determining psychoacoustical threshold curves

    DEFF Research Database (Denmark)

    2016-01-01

    at a second and opposite side of the a priori estimated psychoacoustical threshold curve. A series of auditory stimulus signals in accordance with the respective parameter pairs are presented to the listener through a sound reproduction device and the listener's detection of a predetermined attribute....../feature of the auditory stimulus signals is recorded such that a stimuli path through the predetermined two- dimensional response space is traversed. The psychoacoustical threshold curve is computed based on at least a subset of the recorded parameter pairs....

  1. Auditory-motor learning influences auditory memory for music.

    Science.gov (United States)

    Brown, Rachel M; Palmer, Caroline

    2012-05-01

    In two experiments, we investigated how auditory-motor learning influences performers' memory for music. Skilled pianists learned novel melodies in four conditions: auditory only (listening), motor only (performing without sound), strongly coupled auditory-motor (normal performance), and weakly coupled auditory-motor (performing along with auditory recordings). Pianists' recognition of the learned melodies was better following auditory-only or auditory-motor (weakly coupled and strongly coupled) learning than following motor-only learning, and better following strongly coupled auditory-motor learning than following auditory-only learning. Auditory and motor imagery abilities modulated the learning effects: Pianists with high auditory imagery scores had better recognition following motor-only learning, suggesting that auditory imagery compensated for missing auditory feedback at the learning stage. Experiment 2 replicated the findings of Experiment 1 with melodies that contained greater variation in acoustic features. Melodies that were slower and less variable in tempo and intensity were remembered better following weakly coupled auditory-motor learning. These findings suggest that motor learning can aid performers' auditory recognition of music beyond auditory learning alone, and that motor learning is influenced by individual abilities in mental imagery and by variation in acoustic features.

  2. Effects of moderate-level sound exposure on behavioral thresholds in chinchillas

    OpenAIRE

    Carbajal de Nava, Maria Sandra

    2015-01-01

    Normal audiometric thresholds following noise exposure have generally been considered as an indication of a recovered cochlea and intact peripheral auditory system, yet recent animal work has challenged this classic assumption. Moderately noise-exposed animals have been shown to have permanent loss of synapses on inner hair cells (IHCs) and permanent damage to auditory nerve fibers (ANFs), specifically the low-spontaneous rate fibers (low-SR), despite normal electrophysiological thresholds. L...

  3. Auditory Processing Testing: In the Booth versus Outside the Booth.

    Science.gov (United States)

    Lucker, Jay R

    2017-09-01

    Many audiologists believe that auditory processing testing must be carried out in a soundproof booth. This expectation is especially a problem in places such as elementary schools. Research comparing pure-tone thresholds obtained in sound booths compared to quiet test environments outside of these booths does not support that belief. Auditory processing testing is generally carried out at above threshold levels, and therefore may be even less likely to require a soundproof booth. The present study was carried out to compare test results in soundproof booths versus quiet rooms. The purpose of this study was to determine whether auditory processing tests can be administered in a quiet test room rather than in the soundproof test suite. The outcomes would identify that audiologists can provide auditory processing testing for children under various test conditions including quiet rooms at their school. A battery of auditory processing tests was administered at a test level equivalent to 50 dB HL through headphones. The same equipment was used for testing in both locations. Twenty participants identified with normal hearing were included in this study, ten having no auditory processing concerns and ten exhibiting auditory processing problems. All participants underwent a battery of tests, both inside the test booth and outside the booth in a quiet room. Order of testing (inside versus outside) was counterbalanced. Participants were first determined to have normal hearing thresholds for tones and speech. Auditory processing tests were recorded and presented from an HP EliteBook laptop computer with noise-canceling headphones attached to a y-cord that not only presented the test stimuli to the participants but also allowed monitor headphones to be worn by the evaluator. The same equipment was used inside as well as outside the booth. No differences were found for each auditory processing measure as a function of the test setting or the order in which testing was done

  4. [Auditory processing in specific language disorder].

    Science.gov (United States)

    Idiazábal-Aletxa, M A; Saperas-Rodríguez, M

    2008-01-01

    Specific language impairment (SLI) is diagnosed when a child has difficulty in producing or understanding spoken language for no apparent reason. The diagnosis in made when language development is out of keeping with other aspects of development, and possible explanatory causes have been excluded. During the last years neurosciences have approached to the study of SLI. The ability to process two or more rapidly presented, successive, auditory stimuli is believed to underlie successful language acquisition. It has been proposed that SLI is the consequence of low-level abnormalities in auditory perception. Too, children with SLI show a specific deficit in automatic discrimination of syllables. Electrophysiological methods may reveal underlying immaturity or other abnormality of auditory processing even when behavioural thresholds look normal. There is much controversy about the role of such deficits in causing their language problems, and it has been difficult to establish solid, replicable findings in this area because of the heterogeneity in the population and because insufficient attention has been paid to maturational aspects of auditory processing.

  5. Auditory Integration Training

    Directory of Open Access Journals (Sweden)

    Zahra Jafari

    2002-07-01

    Full Text Available Auditory integration training (AIT is a hearing enhancement training process for sensory input anomalies found in individuals with autism, attention deficit hyperactive disorder, dyslexia, hyperactivity, learning disability, language impairments, pervasive developmental disorder, central auditory processing disorder, attention deficit disorder, depressin, and hyperacute hearing. AIT, recently introduced in the United States, and has received much notice of late following the release of The Sound of a Moracle, by Annabel Stehli. In her book, Mrs. Stehli describes before and after auditory integration training experiences with her daughter, who was diagnosed at age four as having autism.

  6. Review: Auditory Integration Training

    Directory of Open Access Journals (Sweden)

    Zahra Ja'fari

    2003-01-01

    Full Text Available Auditory integration training (AIT is a hearing enhancement training process for sensory input anomalies found in individuals with autism, attention deficit hyperactive disorder, dyslexia, hyperactivity, learning disability, language impairments, pervasive developmental disorder, central auditory processing disorder, attention deficit disorder, depression, and hyper acute hearing. AIT, recently introduced in the United States, and has received much notice of late following the release of the sound of a miracle, by Annabel Stehli. In her book, Mrs. Stehli describes before and after auditory integration training experiences with her daughter, who was diagnosed at age four as having autism.

  7. Plasticity of peripheral auditory frequency sensitivity in Emei music frog.

    Science.gov (United States)

    Zhang, Dian; Cui, Jianguo; Tang, Yezhong

    2012-01-01

    In anurans reproductive behavior is strongly seasonal. During the spring, frogs emerge from hibernation and males vocalize for mating or advertising territories. Female frogs have the ability to evaluate the quality of the males' resources on the basis of these vocalizations. Although studies revealed that central single torus semicircularis neurons in frogs exhibit season plasticity, the plasticity of peripheral auditory sensitivity in frog is unknown. In this study the seasonally plasticity of peripheral auditory sensitivity was test in the Emei music frog Babina daunchina, by comparing thresholds and latencies of auditory brainstem responses (ABRs) evoked by tone pips and clicks in the reproductive and non-reproductive seasons. The results show that both ABR thresholds and latency differ significantly between the reproductive and non-reproductive seasons. The thresholds of tone pip evoked ABRs in the non-reproductive season increased significantly about 10 dB than those in the reproductive season for frequencies from 1 KHz to 6 KHz. ABR latencies to waveform valley values for tone pips for the same frequencies using appropriate threshold stimulus levels are longer than those in the reproductive season for frequencies from 1.5 to 6 KHz range, although from 0.2 to 1.5 KHz range it is shorter in the non-reproductive season. These results demonstrated that peripheral auditory frequency sensitivity exhibits seasonal plasticity changes which may be adaptive to seasonal reproductive behavior in frogs.

  8. Plasticity of peripheral auditory frequency sensitivity in Emei music frog.

    Directory of Open Access Journals (Sweden)

    Dian Zhang

    Full Text Available In anurans reproductive behavior is strongly seasonal. During the spring, frogs emerge from hibernation and males vocalize for mating or advertising territories. Female frogs have the ability to evaluate the quality of the males' resources on the basis of these vocalizations. Although studies revealed that central single torus semicircularis neurons in frogs exhibit season plasticity, the plasticity of peripheral auditory sensitivity in frog is unknown. In this study the seasonally plasticity of peripheral auditory sensitivity was test in the Emei music frog Babina daunchina, by comparing thresholds and latencies of auditory brainstem responses (ABRs evoked by tone pips and clicks in the reproductive and non-reproductive seasons. The results show that both ABR thresholds and latency differ significantly between the reproductive and non-reproductive seasons. The thresholds of tone pip evoked ABRs in the non-reproductive season increased significantly about 10 dB than those in the reproductive season for frequencies from 1 KHz to 6 KHz. ABR latencies to waveform valley values for tone pips for the same frequencies using appropriate threshold stimulus levels are longer than those in the reproductive season for frequencies from 1.5 to 6 KHz range, although from 0.2 to 1.5 KHz range it is shorter in the non-reproductive season. These results demonstrated that peripheral auditory frequency sensitivity exhibits seasonal plasticity changes which may be adaptive to seasonal reproductive behavior in frogs.

  9. Testing auditory sensitivity in the great cormorant (Phalacrocorax carbo sinensis)

    DEFF Research Database (Denmark)

    Maxwell, Alyssa; Hansen, Kirstin Anderson; Larsen, Ole Næsbye

    2016-01-01

    Psychoacoustic and electrophysiological methods were used to measure the in-air hearing sensitivity of the great cormorant (Phalacrocorax carbo sinensis). One individual was used to determine the behavioral thresholds, which was then compared to previously collected data on the auditory brainstem...

  10. Octave-Band Thresholds for Modeled Reverberant Fields

    Science.gov (United States)

    Begault, Durand R.; Wenzel, Elizabeth M.; Tran, Laura L.; Anderson, Mark R.; Trejo, Leonard J. (Technical Monitor)

    1998-01-01

    Auditory thresholds for 10 subjects were obtained for speech stimuli reverberation. The reverberation was produced and manipulated by 3-D audio modeling based on an actual room. The independent variables were octave-band-filtering (bypassed, 0.25 - 2.0 kHz Fc) and reverberation time (0.2- 1.1 sec). An ANOVA revealed significant effects (threshold range: -19 to -35 dB re 60 dB SRL).

  11. Development of visuo-auditory integration in space and time

    Directory of Open Access Journals (Sweden)

    Monica eGori

    2012-09-01

    Full Text Available Adults integrate multisensory information optimally (e.g. Ernst & Banks, 2002 while children are not able to integrate multisensory visual haptic cues until 8-10 years of age (e.g. Gori, Del Viva, Sandini, & Burr, 2008. Before that age strong unisensory dominance is present for size and orientation visual-haptic judgments maybe reflecting a process of cross-sensory calibration between modalities. It is widely recognized that audition dominates time perception, while vision dominates space perception. If the cross sensory calibration process is necessary for development, then the auditory modality should calibrate vision in a bimodal temporal task, and the visual modality should calibrate audition in a bimodal spatial task. Here we measured visual-auditory integration in both the temporal and the spatial domains reproducing for the spatial task a child-friendly version of the ventriloquist stimuli used by Alais and Burr (2004 and for the temporal task a child-friendly version of the stimulus used by Burr, Banks and Morrone (2009. Unimodal and bimodal (conflictual or not conflictual audio-visual thresholds and PSEs were measured and compared with the Bayesian predictions. In the temporal domain, we found that both in children and adults, audition dominates the bimodal visuo-auditory task both in perceived time and precision thresholds. Contrarily, in the visual-auditory spatial task, children younger than 12 years of age show clear visual dominance (on PSEs and bimodal thresholds higher than the Bayesian prediction. Only in the adult group bimodal thresholds become optimal. In agreement with previous studies, our results suggest that also visual-auditory adult-like behaviour develops late. Interestingly, the visual dominance for space and the auditory dominance for time that we found might suggest a cross-sensory comparison of vision in a spatial visuo-audio task and a cross-sensory comparison of audition in a temporal visuo-audio task.

  12. Inconsistent Effect of Arousal on Early Auditory Perception.

    Science.gov (United States)

    Bolders, Anna C; Band, Guido P H; Stallen, Pieter Jan M

    2017-01-01

    Mood has been shown to influence cognitive performance. However, little is known about the influence of mood on sensory processing, specifically in the auditory domain. With the current study, we sought to investigate how auditory processing of neutral sounds is affected by the mood state of the listener. This was tested in two experiments by measuring masked-auditory detection thresholds before and after a standard mood-induction procedure. In the first experiment ( N = 76), mood was induced by imagining a mood-appropriate event combined with listening to mood inducing music. In the second experiment ( N = 80), imagining was combined with affective picture viewing to exclude any possibility of confounding the results by acoustic properties of the music. In both experiments, the thresholds were determined by means of an adaptive staircase tracking method in a two-interval forced-choice task. Masked detection thresholds were compared between participants in four different moods (calm, happy, sad, and anxious), which enabled differentiation of mood effects along the dimensions arousal and pleasure. Results of the two experiments were analyzed both in separate analyses and in a combined analysis. The first experiment showed that, while there was no impact of pleasure level on the masked threshold, lower arousal was associated with lower threshold (higher masked sensitivity). However, as indicated by an interaction effect between experiment and arousal, arousal did have a different effect on the threshold in Experiment 2. Experiment 2 showed a trend of arousal in opposite direction. These results show that the effect of arousal on auditory-masked sensitivity may depend on the modality of the mood-inducing stimuli. As clear conclusions regarding the genuineness of the arousal effect on the masked threshold cannot be drawn, suggestions for further research that could clarify this issue are provided.

  13. Aktiverende Undervisning i auditorier

    DEFF Research Database (Denmark)

    Parus, Judith

    Workshop om erfaringer og brug af aktiverende metoder i undervisning i auditorier og på store hold. Hvilke metoder har fungeret godt og hvilke dårligt ? Hvilke overvejelser skal man gøre sig.......Workshop om erfaringer og brug af aktiverende metoder i undervisning i auditorier og på store hold. Hvilke metoder har fungeret godt og hvilke dårligt ? Hvilke overvejelser skal man gøre sig....

  14. An Auditory Model with Hearing Loss

    DEFF Research Database (Denmark)

    Nielsen, Lars Bramsløw

    An auditory model based on the psychophysics of hearing has been developed and tested. The model simulates the normal ear or an impaired ear with a given hearing loss. Based on reviews of the current literature, the frequency selectivity and loudness growth as functions of threshold and stimulus...... level have been found and implemented in the model. The auditory model was verified against selected results from the literature, and it was confirmed that the normal spread of masking and loudness growth could be simulated in the model. The effects of hearing loss on these parameters was also...... in qualitative agreement with recent findings. The temporal properties of the ear have currently not been included in the model. As an example of a real-world application of the model, loudness spectrograms for a speech utterance were presented. By introducing hearing loss, the speech sounds became less audible...

  15. Auditory Spatial Layout

    Science.gov (United States)

    Wightman, Frederic L.; Jenison, Rick

    1995-01-01

    All auditory sensory information is packaged in a pair of acoustical pressure waveforms, one at each ear. While there is obvious structure in these waveforms, that structure (temporal and spectral patterns) bears no simple relationship to the structure of the environmental objects that produced them. The properties of auditory objects and their layout in space must be derived completely from higher level processing of the peripheral input. This chapter begins with a discussion of the peculiarities of acoustical stimuli and how they are received by the human auditory system. A distinction is made between the ambient sound field and the effective stimulus to differentiate the perceptual distinctions among various simple classes of sound sources (ambient field) from the known perceptual consequences of the linear transformations of the sound wave from source to receiver (effective stimulus). Next, the definition of an auditory object is dealt with, specifically the question of how the various components of a sound stream become segregated into distinct auditory objects. The remainder of the chapter focuses on issues related to the spatial layout of auditory objects, both stationary and moving.

  16. CARA Risk Assessment Thresholds

    Science.gov (United States)

    Hejduk, M. D.

    2016-01-01

    Warning remediation threshold (Red threshold): Pc level at which warnings are issued, and active remediation considered and usually executed. Analysis threshold (Green to Yellow threshold): Pc level at which analysis of event is indicated, including seeking additional information if warranted. Post-remediation threshold: Pc level to which remediation maneuvers are sized in order to achieve event remediation and obviate any need for immediate follow-up maneuvers. Maneuver screening threshold: Pc compliance level for routine maneuver screenings (more demanding than regular Red threshold due to additional maneuver uncertainty).

  17. Air and Bone Conduction Frequency-specific Auditory Brainstem Response in Children with Agenesis of the External Auditory Canal.

    Science.gov (United States)

    Sleifer, Pricila; Didoné, Dayane Domeneghini; Keppeler, Ísis Bicca; Bueno, Claudine Devicari; Riesgo, Rudimar Dos Santos

    2017-10-01

    Introduction  The tone-evoked auditory brainstem responses (tone-ABR) enable the differential diagnosis in the evaluation of children until 12 months of age, including those with external and/or middle ear malformations. The use of auditory stimuli with frequency specificity by air and bone conduction allows characterization of hearing profile. Objective  The objective of our study was to compare the results obtained in tone-ABR by air and bone conduction in children until 12 months, with agenesis of the external auditory canal. Method  The study was cross-sectional, observational, individual, and contemporary. We conducted the research with tone-ABR by air and bone conduction in the frequencies of 500 Hz and 2000 Hz in 32 children, 23 boys, from one to 12 months old, with agenesis of the external auditory canal. Results  The tone-ABR thresholds were significantly elevated for air conduction in the frequencies of 500 Hz and 2000 Hz, while the thresholds of bone conduction had normal values in both ears. We found no statistically significant difference between genders and ears for most of the comparisons. Conclusion  The thresholds obtained by bone conduction did not alter the thresholds in children with conductive hearing loss. However, the conductive hearing loss alter all thresholds by air conduction. The tone-ABR by bone conduction is an important tool for assessing cochlear integrity in children with agenesis of the external auditory canal under 12 months.

  18. A Nonlinear Transmission Line Model of the Cochlea With Temporal Integration Accounts for Duration Effects in Threshold Fine Structure

    DEFF Research Database (Denmark)

    Verhey, Jesko L.; Mauermann, Manfred; Epp, Bastian

    2017-01-01

    For normal-hearing listeners, auditory pure-tone thresholds in quiet often show quasi periodic fluctuations when measured with a high frequency resolution, referred to as threshold fine structure. Threshold fine structure is dependent on the stimulus duration, with smaller fluctuations for short ...

  19. Acoustic Noise of MRI Scans of the Internal Auditory Canal and Potential for Intracochlear Physiological Changes

    CERN Document Server

    Busada, M A; Ibrahim, G; Huckans, J H

    2012-01-01

    Magnetic resonance imaging (MRI) is a widely used medical imaging technique to assess the health of the auditory (vestibulocochlear) nerve. A well known problem with MRI machines is that the acoustic noise they generate during a scan can cause auditory temporary threshold shifts (TTS) in humans. In addition, studies have shown that excessive noise in general can cause rapid physiological changes of constituents of the auditory within the cochlea. Here, we report in-situ measurements of the acoustic noise from a 1.5 Tesla MRI machine (GE Signa) during scans specific to auditory nerve assessment. The measured average and maximum noise levels corroborate earlier investigations where TTS occurred. We briefly discuss the potential for physiological changes to the intracochlear branches of the auditory nerve as well as iatrogenic misdiagnoses of intralabyrinthine and intracochlear schwannomas due to hypertrophe of the auditory nerve within the cochlea during MRI assessment.

  20. [Detection of auditory impairment in the offsprings caused by drug treatment of the dams].

    Science.gov (United States)

    Kameyama, T; Nabeshima, T; Itoh, J

    1982-12-01

    To study the auditory impairment induced by prenatal administration of aminoglycosides in the offspring, the shuttle box method to measure the auditory threshold of rats (Kameyama et al., Folia pharmacol. japon. 77, 15, 1981) was employed. Four groups of pregnant rats were administered 200 mg/kg kanamycin sulfate (KM), 200 mg/kg dihydrostreptomycin sulfate (DHSM), 100 mg/kg neomycin sulfate (NM), or 1 ml/kg saline intramuscularly from the 10th to the 19th day of pregnancy. The auditory threshold of the offspring could be measured by the shuttle box method in about 90% of the live born rats at the age of 100 days. The auditory thresholds of the groups were as follows (mean +/- S.E.): saline group, 53.8 +/- 0.6 dB (N = 36); KM group, 63.8 +/- 1.1 dB (N = 34); DHSM group, 60.0 +/- 1.2 dB (N = 29); NM group, 62.4 +/- 1.2 dB (N = 24). Auditory thresholds of drug-treated groups were significantly higher than that of the saline group. However, no increase in the auditory threshold of the mother rat was detected after treatment with aminoglycosides. In addition, the experimental procedure of the shuttle box method is very easy, and the auditory threshold of a large number of rats could be measured in a short period. These findings suggest that this method is a very useful one for screening for auditory impairment induced by prenatal drug treatment in rat offspring.

  1. Auditory hallucinations induced by trazodone

    Science.gov (United States)

    Shiotsuki, Ippei; Terao, Takeshi; Ishii, Nobuyoshi; Hatano, Koji

    2014-01-01

    A 26-year-old female outpatient presenting with a depressive state suffered from auditory hallucinations at night. Her auditory hallucinations did not respond to blonanserin or paliperidone, but partially responded to risperidone. In view of the possibility that her auditory hallucinations began after starting trazodone, trazodone was discontinued, leading to a complete resolution of her auditory hallucinations. Furthermore, even after risperidone was decreased and discontinued, her auditory hallucinations did not recur. These findings suggest that trazodone may induce auditory hallucinations in some susceptible patients. PMID:24700048

  2. Integration of auditory and visual speech information

    NARCIS (Netherlands)

    Hall, M.; Smeele, P.M.T.; Kuhl, P.K.

    1998-01-01

    The integration of auditory and visual speech is observed when modes specify different places of articulation. Influences of auditory variation on integration were examined using consonant identifi-cation, plus quality and similarity ratings. Auditory identification predicted auditory-visual

  3. Musical Experience, Auditory Perception and Reading-Related Skills in Children

    Science.gov (United States)

    Banai, Karen; Ahissar, Merav

    2013-01-01

    Background The relationships between auditory processing and reading-related skills remain poorly understood despite intensive research. Here we focus on the potential role of musical experience as a confounding factor. Specifically we ask whether the pattern of correlations between auditory and reading related skills differ between children with different amounts of musical experience. Methodology/Principal Findings Third grade children with various degrees of musical experience were tested on a battery of auditory processing and reading related tasks. Very poor auditory thresholds and poor memory skills were abundant only among children with no musical education. In this population, indices of auditory processing (frequency and interval discrimination thresholds) were significantly correlated with and accounted for up to 13% of the variance in reading related skills. Among children with more than one year of musical training, auditory processing indices were better, yet reading related skills were not correlated with them. A potential interpretation for the reduction in the correlations might be that auditory and reading-related skills improve at different rates as a function of musical training. Conclusions/Significance Participants’ previous musical training, which is typically ignored in studies assessing the relations between auditory and reading related skills, should be considered. Very poor auditory and memory skills are rare among children with even a short period of musical training, suggesting musical training could have an impact on both. The lack of correlation in the musically trained population suggests that a short period of musical training does not enhance reading related skills of individuals with within-normal auditory processing skills. Further studies are required to determine whether the associations between musical training, auditory processing and memory are indeed causal or whether children with poor auditory and memory skills are less

  4. Musical experience, auditory perception and reading-related skills in children.

    Science.gov (United States)

    Banai, Karen; Ahissar, Merav

    2013-01-01

    The relationships between auditory processing and reading-related skills remain poorly understood despite intensive research. Here we focus on the potential role of musical experience as a confounding factor. Specifically we ask whether the pattern of correlations between auditory and reading related skills differ between children with different amounts of musical experience. Third grade children with various degrees of musical experience were tested on a battery of auditory processing and reading related tasks. Very poor auditory thresholds and poor memory skills were abundant only among children with no musical education. In this population, indices of auditory processing (frequency and interval discrimination thresholds) were significantly correlated with and accounted for up to 13% of the variance in reading related skills. Among children with more than one year of musical training, auditory processing indices were better, yet reading related skills were not correlated with them. A potential interpretation for the reduction in the correlations might be that auditory and reading-related skills improve at different rates as a function of musical training. Participants' previous musical training, which is typically ignored in studies assessing the relations between auditory and reading related skills, should be considered. Very poor auditory and memory skills are rare among children with even a short period of musical training, suggesting musical training could have an impact on both. The lack of correlation in the musically trained population suggests that a short period of musical training does not enhance reading related skills of individuals with within-normal auditory processing skills. Further studies are required to determine whether the associations between musical training, auditory processing and memory are indeed causal or whether children with poor auditory and memory skills are less likely to study music and if so, why this is the case.

  5. Musical experience, auditory perception and reading-related skills in children.

    Directory of Open Access Journals (Sweden)

    Karen Banai

    Full Text Available BACKGROUND: The relationships between auditory processing and reading-related skills remain poorly understood despite intensive research. Here we focus on the potential role of musical experience as a confounding factor. Specifically we ask whether the pattern of correlations between auditory and reading related skills differ between children with different amounts of musical experience. METHODOLOGY/PRINCIPAL FINDINGS: Third grade children with various degrees of musical experience were tested on a battery of auditory processing and reading related tasks. Very poor auditory thresholds and poor memory skills were abundant only among children with no musical education. In this population, indices of auditory processing (frequency and interval discrimination thresholds were significantly correlated with and accounted for up to 13% of the variance in reading related skills. Among children with more than one year of musical training, auditory processing indices were better, yet reading related skills were not correlated with them. A potential interpretation for the reduction in the correlations might be that auditory and reading-related skills improve at different rates as a function of musical training. CONCLUSIONS/SIGNIFICANCE: Participants' previous musical training, which is typically ignored in studies assessing the relations between auditory and reading related skills, should be considered. Very poor auditory and memory skills are rare among children with even a short period of musical training, suggesting musical training could have an impact on both. The lack of correlation in the musically trained population suggests that a short period of musical training does not enhance reading related skills of individuals with within-normal auditory processing skills. Further studies are required to determine whether the associations between musical training, auditory processing and memory are indeed causal or whether children with poor auditory and

  6. Effect of age at cochlear implantation on auditory and speech development of children with auditory neuropathy spectrum disorder.

    Science.gov (United States)

    Liu, Yuying; Dong, Ruijuan; Li, Yuling; Xu, Tianqiu; Li, Yongxin; Chen, Xueqing; Gong, Shusheng

    2014-12-01

    To evaluate the auditory and speech abilities in children with auditory neuropathy spectrum disorder (ANSD) after cochlear implantation (CI) and determine the role of age at implantation. Ten children participated in this retrospective case series study. All children had evidence of ANSD. All subjects had no cochlear nerve deficiency on magnetic resonance imaging and had used the cochlear implants for a period of 12-84 months. We divided our children into two groups: children who underwent implantation before 24 months of age and children who underwent implantation after 24 months of age. Their auditory and speech abilities were evaluated using the following: behavioral audiometry, the Categories of Auditory Performance (CAP), the Meaningful Auditory Integration Scale (MAIS), the Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS), the Standard-Chinese version of the Monosyllabic Lexical Neighborhood Test (LNT), the Multisyllabic Lexical Neighborhood Test (MLNT), the Speech Intelligibility Rating (SIR) and the Meaningful Use of Speech Scale (MUSS). All children showed progress in their auditory and language abilities. The 4-frequency average hearing level (HL) (500Hz, 1000Hz, 2000Hz and 4000Hz) of aided hearing thresholds ranged from 17.5 to 57.5dB HL. All children developed time-related auditory perception and speech skills. Scores of children with ANSD who received cochlear implants before 24 months tended to be better than those of children who received cochlear implants after 24 months. Seven children completed the Mandarin Lexical Neighborhood Test. Approximately half of the children showed improved open-set speech recognition. Cochlear implantation is helpful for children with ANSD and may be a good optional treatment for many ANSD children. In addition, children with ANSD fitted with cochlear implants before 24 months tended to acquire auditory and speech skills better than children fitted with cochlear implants after 24 months. Copyright © 2014

  7. Octave effect in auditory attention

    National Research Council Canada - National Science Library

    Tobias Borra; Huib Versnel; Chantal Kemner; A. John van Opstal; Raymond van Ee

    2013-01-01

    ... tones. Current auditory models explain this phenomenon by a simple bandpass attention filter. Here, we demonstrate that auditory attention involves multiple pass-bands around octave-related frequencies above and below the cued tone...

  8. Auditory and Visual Sensations

    CERN Document Server

    Ando, Yoichi

    2010-01-01

    Professor Yoichi Ando, acoustic architectural designer of the Kirishima International Concert Hall in Japan, presents a comprehensive rational-scientific approach to designing performance spaces. His theory is based on systematic psychoacoustical observations of spatial hearing and listener preferences, whose neuronal correlates are observed in the neurophysiology of the human brain. A correlation-based model of neuronal signal processing in the central auditory system is proposed in which temporal sensations (pitch, timbre, loudness, duration) are represented by an internal autocorrelation representation, and spatial sensations (sound location, size, diffuseness related to envelopment) are represented by an internal interaural crosscorrelation function. Together these two internal central auditory representations account for the basic auditory qualities that are relevant for listening to music and speech in indoor performance spaces. Observed psychological and neurophysiological commonalities between auditor...

  9. Auditory Neuropathy: Findings of Behavioral, Physiological and Neurophysiological Tests

    Directory of Open Access Journals (Sweden)

    Mohammad Farhadi

    2006-12-01

    Full Text Available Background and Aim: Auditory neuropathy (AN can be diagnosed by abnormal auditory brainstem response (ABR, in the presence of normal cochlear microphonic (CM and otoacoustic emissions (OAEs.The aim of this study was to investigate the ABR and other electrodiagnostic test results of 6 patients suspicious to AN with problems in speech recognition. Materials and Methods: this cross sectional study was conducted on 6 AN patients with different ages evaluated by pure tone audiometry, speech discrimination score (SDS , immittance audiometry. ElectroCochleoGraphy , ABR, middle latency response (MLR, Late latency response (LLR, and OAEs. Results: Behavioral pure tone audiometric tests showed moderate to profound hearing loss. SDS was so poor which is not in accordance with pure tone thresholds. All patients had normal tympanogram but absent acoustic reflexes. CMs and OAEs were within normal limits. There was no contra lateral suppression of OAEs. None of cases had normal ABR or MLR although LLR was recorded in 4. Conclusion: All patients in this study are typical cases of auditory neuropathy. Despite having abnormal input, LLR remains normal that indicates differences in auditory evoked potentials related to required neural synchrony. These findings show that auditory cortex may play a role in regulating presentation of deficient signals along auditory pathways in primary steps.

  10. Neurotrophic factor intervention restores auditory function in deafened animals

    Science.gov (United States)

    Shinohara, Takayuki; Bredberg, Göran; Ulfendahl, Mats; Pyykkö, Ilmari; Petri Olivius, N.; Kaksonen, Risto; Lindström, Bo; Altschuler, Richard; Miller, Josef M.

    2002-02-01

    A primary cause of deafness is damage of receptor cells in the inner ear. Clinically, it has been demonstrated that effective functionality can be provided by electrical stimulation of the auditory nerve, thus bypassing damaged receptor cells. However, subsequent to sensory cell loss there is a secondary degeneration of the afferent nerve fibers, resulting in reduced effectiveness of such cochlear prostheses. The effects of neurotrophic factors were tested in a guinea pig cochlear prosthesis model. After chemical deafening to mimic the clinical situation, the neurotrophic factors brain-derived neurotrophic factor and an analogue of ciliary neurotrophic factor were infused directly into the cochlea of the inner ear for 26 days by using an osmotic pump system. An electrode introduced into the cochlea was used to elicit auditory responses just as in patients implanted with cochlear prostheses. Intervention with brain-derived neurotrophic factor and the ciliary neurotrophic factor analogue not only increased the survival of auditory spiral ganglion neurons, but significantly enhanced the functional responsiveness of the auditory system as measured by using electrically evoked auditory brainstem responses. This demonstration that neurotrophin intervention enhances threshold sensitivity within the auditory system will have great clinical importance for the treatment of deaf patients with cochlear prostheses. The findings have direct implications for the enhancement of responsiveness in deafferented peripheral nerves.

  11. Transcranial Random Noise Stimulation (tRNS Shapes the Processing of Rapidly Changing Auditory Information

    Directory of Open Access Journals (Sweden)

    Katharina S. Rufener

    2017-06-01

    Full Text Available Neural oscillations in the gamma range are the dominant rhythmic activation pattern in the human auditory cortex. These gamma oscillations are functionally relevant for the processing of rapidly changing acoustic information in both speech and non-speech sounds. Accordingly, there is a tight link between the temporal resolution ability of the auditory system and inherent neural gamma oscillations. Transcranial random noise stimulation (tRNS has been demonstrated to specifically increase gamma oscillation in the human auditory cortex. However, neither the physiological mechanisms of tRNS nor the behavioral consequences of this intervention are completely understood. In the present study we stimulated the human auditory cortex bilaterally with tRNS while EEG was continuously measured. Modulations in the participants’ temporal and spectral resolution ability were investigated by means of a gap detection task and a pitch discrimination task. Compared to sham, auditory tRNS increased the detection rate for near-threshold stimuli in the temporal domain only, while no such effect was present for the discrimination of spectral features. Behavioral findings were paralleled by reduced peak latencies of the P50 and N1 component of the auditory event-related potentials (ERP indicating an impact on early sensory processing. The facilitating effect of tRNS was limited to the processing of near-threshold stimuli while stimuli clearly below and above the individual perception threshold were not affected by tRNS. This non-linear relationship between the signal-to-noise level of the presented stimuli and the effect of stimulation further qualifies stochastic resonance (SR as the underlying mechanism of tRNS on auditory processing. Our results demonstrate a tRNS related improvement in acoustic perception of time critical auditory information and, thus, provide further indices that auditory tRNS can amplify the resonance frequency of the auditory system.

  12. Exact Threshold Circuits

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Podolskii, Vladimir V.

    2010-01-01

    with the well-studied corresponding hierarchies defined using ordinary threshold gates. A major open problem in Boolean circuit complexity is to provide an explicit super-polynomial lower bound for depth two threshold circuits. We identify the class of depth two exact threshold circuits as a natural subclass...

  13. Threshold Concepts in Biochemistry

    Science.gov (United States)

    Loertscher, Jennifer

    2011-01-01

    Threshold concepts can be identified for any discipline and provide a framework for linking student learning to curricular design. Threshold concepts represent a transformed understanding of a discipline, without which the learner cannot progress and are therefore pivotal in learning in a discipline. Although threshold concepts have been…

  14. Sub-threshold synchronizer

    NARCIS (Netherlands)

    Zhou, J.; Ashouei, M.; Kinniment, D.; Huisken, J.; Russell, G.; Yakovlev, A.

    2011-01-01

    Sub-threshold operation has been proven to be very effective to reduce the power consumption of circuits when high performance is not required. Future low power systems on chip are likely to consist of many sub-systems operating at different frequencies and VDDs from super-threshold to sub-threshold

  15. Auditory agnosia as a clinical symptom of childhood adrenoleukodystrophy.

    Science.gov (United States)

    Furushima, Wakana; Kaga, Makiko; Nakamura, Masako; Gunji, Atsuko; Inagaki, Masumi

    2015-08-01

    To investigate detailed auditory features in patients with auditory impairment as the first clinical symptoms of childhood adrenoleukodystrophy (CSALD). Three patients who had hearing difficulty as the first clinical signs and/or symptoms of ALD. Precise examination of the clinical characteristics of hearing and auditory function was performed, including assessments of pure tone audiometry, verbal sound discrimination, otoacoustic emission (OAE), and auditory brainstem response (ABR), as well as an environmental sound discrimination test, a sound lateralization test, and a dichotic listening test (DLT). The auditory pathway was evaluated by MRI in each patient. Poor response to calling was detected in all patients. Two patients were not aware of their hearing difficulty, and had been diagnosed with normal hearing by otolaryngologists at first. Pure-tone audiometry disclosed normal hearing in all patients. All patients showed a normal wave V ABR threshold. Three patients showed obvious difficulty in discriminating verbal sounds, environmental sounds, and sound lateralization and strong left-ear suppression in a dichotic listening test. However, once they discriminated verbal sounds, they correctly understood the meaning. Two patients showed elongation of the I-V and III-V interwave intervals in ABR, but one showed no abnormality. MRIs of these three patients revealed signal changes in auditory radiation including in other subcortical areas. The hearing features of these subjects were diagnosed as auditory agnosia and not aphasia. It should be emphasized that when patients are suspected to have hearing impairment but have no abnormalities in pure tone audiometry and/or ABR, this should not be diagnosed immediately as psychogenic response or pathomimesis, but auditory agnosia must also be considered. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  16. A comparison of auditory brainstem responses across diving bird species

    Science.gov (United States)

    Crowell, Sara E.; Berlin, Alicia; Carr, Catherine E; Olsen, Glenn H.; Therrien, Ronald E; Yannuzzi, Sally E; Ketten, Darlene R

    2015-01-01

    There is little biological data available for diving birds because many live in hard-to-study, remote habitats. Only one species of diving bird, the black-footed penguin (Spheniscus demersus), has been studied in respect to auditory capabilities (Wever et al., Proc Natl Acad Sci USA 63:676–680, 1969). We, therefore, measured in-air auditory threshold in ten species of diving birds, using the auditory brainstem response (ABR). The average audiogram obtained for each species followed the U-shape typical of birds and many other animals. All species tested shared a common region of the greatest sensitivity, from 1000 to 3000 Hz, although audiograms differed significantly across species. Thresholds of all duck species tested were more similar to each other than to the two non-duck species tested. The red-throated loon (Gavia stellata) and northern gannet (Morus bassanus) exhibited the highest thresholds while the lowest thresholds belonged to the duck species, specifically the lesser scaup (Aythya affinis) and ruddy duck (Oxyura jamaicensis). Vocalization parameters were also measured for each species, and showed that with the exception of the common eider (Somateria mollisima), the peak frequency, i.e., frequency at the greatest intensity, of all species' vocalizations measured here fell between 1000 and 3000 Hz, matching the bandwidth of the most sensitive hearing range.

  17. Incidental auditory category learning.

    Science.gov (United States)

    Gabay, Yafit; Dick, Frederic K; Zevin, Jason D; Holt, Lori L

    2015-08-01

    Very little is known about how auditory categories are learned incidentally, without instructions to search for category-diagnostic dimensions, overt category decisions, or experimenter-provided feedback. This is an important gap because learning in the natural environment does not arise from explicit feedback and there is evidence that the learning systems engaged by traditional tasks are distinct from those recruited by incidental category learning. We examined incidental auditory category learning with a novel paradigm, the Systematic Multimodal Associations Reaction Time (SMART) task, in which participants rapidly detect and report the appearance of a visual target in 1 of 4 possible screen locations. Although the overt task is rapid visual detection, a brief sequence of sounds precedes each visual target. These sounds are drawn from 1 of 4 distinct sound categories that predict the location of the upcoming visual target. These many-to-one auditory-to-visuomotor correspondences support incidental auditory category learning. Participants incidentally learn categories of complex acoustic exemplars and generalize this learning to novel exemplars and tasks. Further, learning is facilitated when category exemplar variability is more tightly coupled to the visuomotor associations than when the same stimulus variability is experienced across trials. We relate these findings to phonetic category learning. (c) 2015 APA, all rights reserved).

  18. Modelling auditory attention.

    Science.gov (United States)

    Kaya, Emine Merve; Elhilali, Mounya

    2017-02-19

    Sounds in everyday life seldom appear in isolation. Both humans and machines are constantly flooded with a cacophony of sounds that need to be sorted through and scoured for relevant information-a phenomenon referred to as the 'cocktail party problem'. A key component in parsing acoustic scenes is the role of attention, which mediates perception and behaviour by focusing both sensory and cognitive resources on pertinent information in the stimulus space. The current article provides a review of modelling studies of auditory attention. The review highlights how the term attention refers to a multitude of behavioural and cognitive processes that can shape sensory processing. Attention can be modulated by 'bottom-up' sensory-driven factors, as well as 'top-down' task-specific goals, expectations and learned schemas. Essentially, it acts as a selection process or processes that focus both sensory and cognitive resources on the most relevant events in the soundscape; with relevance being dictated by the stimulus itself (e.g. a loud explosion) or by a task at hand (e.g. listen to announcements in a busy airport). Recent computational models of auditory attention provide key insights into its role in facilitating perception in cluttered auditory scenes.This article is part of the themed issue 'Auditory and visual scene analysis'. © 2017 The Authors.

  19. Auditory Channel Problems.

    Science.gov (United States)

    Mann, Philip H.; Suiter, Patricia A.

    This teacher's guide contains a list of general auditory problem areas where students have the following problems: (a) inability to find or identify source of sound; (b) difficulty in discriminating sounds of words and letters; (c) difficulty with reproducing pitch, rhythm, and melody; (d) difficulty in selecting important from unimportant sounds;…

  20. Auditory evoked potentials in a newborn Wistar rat model of hyperbilirubinemia.

    Science.gov (United States)

    Gökdoğan, Çağıl; Genç, Aydan; Gülbahar, Özlem; Gökdoğan, Ozan; Helvacı, Ayşe; Bezgin, Selin Üstün; Memiş, Leyla

    2016-01-01

    Hyperbilirubinemia is a common health problem in newborns. Its effects can be different according to the level and duration of the hyperbilirubinemia. The toxic effect of bilirubin on the auditory system can be seen as a sensory neural hearing loss or auditory neuropathy spectrum disorder (ANSD). The purpose of our study was to determine the effects of toxic bilirubin level on the auditory system by using Auditory Brainstem Response audiometry. Rats are used as animal models due to their low cost and easy attainability. Auditory Brainstem Response was used for auditory assessment. In this study, three groups were established: experimental, control and placebo groups. In the experimental group, which consists of rats with hyperbilirubinemia, sensory neural hearing loss was found bilaterally in 4 rats (66.67%) and unilaterally in 2 rats (16.67%) and auditory neuropathy spectrum disorder was found unilaterally in 1 rat (8.33%). Auditory Brainstem Response thresholds were significantly elevated compared to control and placebo groups (p<0.05). Hyperbilirubinemia of newborn rats may result both in sensory neural hearing loss and auditory neuropathy spectrum disorder. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  1. Auditory evoked potentials in a newborn Wistar rat model of hyperbilirubinemia

    Directory of Open Access Journals (Sweden)

    Çagil Gökdogan

    2016-04-01

    Full Text Available ABSTRACT INTRODUCTION: Hyperbilirubinemia is a common health problem in newborns. Its effects can be different according to the level and duration of the hyperbilirubinemia. The toxic effect of bilirubin on the auditory system can be seen as a sensory neural hearing loss or auditory neuropathy spectrum disorder (ANSD. OBJECTIVE: The purpose of our study was to determine the effects of toxic bilirubin level on the auditory system by using Auditory Brainstem Response audiometry. METHODS: Rats are used as animal models due to their low cost and easy attainability. Auditory Brainstem Response was used for auditory assessment. In this study, three groups were established: experimental, control and placebo groups. RESULTS: In the experimental group, which consists of rats with hyperbilirubinemia, sensory neural hearing loss was found bilaterally in 4 rats (66.67% and unilaterally in 2 rats (16.67% and auditory neuropathy spectrum disorder was found unilaterally in 1 rat (8.33%. Auditory Brainstem Response thresholds were significantly elevated compared to control and placebo groups (p < 0.05. CONCLUSION: Hyperbilirubinemia of newborn rats may result both in sensory neural hearing loss and auditory neuropathy spectrum disorder.

  2. Auditory pathways: anatomy and physiology.

    Science.gov (United States)

    Pickles, James O

    2015-01-01

    This chapter outlines the anatomy and physiology of the auditory pathways. After a brief analysis of the external, middle ears, and cochlea, the responses of auditory nerve fibers are described. The central nervous system is analyzed in more detail. A scheme is provided to help understand the complex and multiple auditory pathways running through the brainstem. The multiple pathways are based on the need to preserve accurate timing while extracting complex spectral patterns in the auditory input. The auditory nerve fibers branch to give two pathways, a ventral sound-localizing stream, and a dorsal mainly pattern recognition stream, which innervate the different divisions of the cochlear nucleus. The outputs of the two streams, with their two types of analysis, are progressively combined in the inferior colliculus and onwards, to produce the representation of what can be called the "auditory objects" in the external world. The progressive extraction of critical features in the auditory stimulus in the different levels of the central auditory system, from cochlear nucleus to auditory cortex, is described. In addition, the auditory centrifugal system, running from cortex in multiple stages to the organ of Corti of the cochlea, is described. © 2015 Elsevier B.V. All rights reserved.

  3. Auditory object cognition in dementia

    Science.gov (United States)

    Goll, Johanna C.; Kim, Lois G.; Hailstone, Julia C.; Lehmann, Manja; Buckley, Aisling; Crutch, Sebastian J.; Warren, Jason D.

    2011-01-01

    The cognition of nonverbal sounds in dementia has been relatively little explored. Here we undertook a systematic study of nonverbal sound processing in patient groups with canonical dementia syndromes comprising clinically diagnosed typical amnestic Alzheimer's disease (AD; n = 21), progressive nonfluent aphasia (PNFA; n = 5), logopenic progressive aphasia (LPA; n = 7) and aphasia in association with a progranulin gene mutation (GAA; n = 1), and in healthy age-matched controls (n = 20). Based on a cognitive framework treating complex sounds as ‘auditory objects’, we designed a novel neuropsychological battery to probe auditory object cognition at early perceptual (sub-object), object representational (apperceptive) and semantic levels. All patients had assessments of peripheral hearing and general neuropsychological functions in addition to the experimental auditory battery. While a number of aspects of auditory object analysis were impaired across patient groups and were influenced by general executive (working memory) capacity, certain auditory deficits had some specificity for particular dementia syndromes. Patients with AD had a disproportionate deficit of auditory apperception but preserved timbre processing. Patients with PNFA had salient deficits of timbre and auditory semantic processing, but intact auditory size and apperceptive processing. Patients with LPA had a generalised auditory deficit that was influenced by working memory function. In contrast, the patient with GAA showed substantial preservation of auditory function, but a mild deficit of pitch direction processing and a more severe deficit of auditory apperception. The findings provide evidence for separable stages of auditory object analysis and separable profiles of impaired auditory object cognition in different dementia syndromes. PMID:21689671

  4. Polynomial threshold functions and Boolean threshold circuits

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Arnsfelt; Podolskii, Vladimir V.

    2013-01-01

    We study the complexity of computing Boolean functions on general Boolean domains by polynomial threshold functions (PTFs). A typical example of a general Boolean domain is 12n . We are mainly interested in the length (the number of monomials) of PTFs, with their degree and weight being of second......We study the complexity of computing Boolean functions on general Boolean domains by polynomial threshold functions (PTFs). A typical example of a general Boolean domain is 12n . We are mainly interested in the length (the number of monomials) of PTFs, with their degree and weight being...

  5. Auditory Reserve and the Legacy of Auditory Experience

    OpenAIRE

    Skoe, Erika; Kraus, Nina

    2014-01-01

    Musical training during childhood has been linked to more robust encoding of sound later in life. We take this as evidence for an auditory reserve: a mechanism by which individuals capitalize on earlier life experiences to promote auditory processing. We assert that early auditory experiences guide how the reserve develops and is maintained over the lifetime. Experiences that occur after childhood, or which are limited in nature, are theorized to affect the reserve, although their influence o...

  6. Resistive Threshold Logic

    OpenAIRE

    James, A. P.; Francis, L. R. V. J.; Kumar, D.

    2013-01-01

    We report a resistance based threshold logic family useful for mimicking brain like large variable logic functions in VLSI. A universal Boolean logic cell based on an analog resistive divider and threshold logic circuit is presented. The resistive divider is implemented using memristors and provides output voltage as a summation of weighted product of input voltages. The output of resistive divider is converted into a binary value by a threshold operation implemented by CMOS inverter and/or O...

  7. Difference thresholds for interaural intensity

    Energy Technology Data Exchange (ETDEWEB)

    Hafter, E.R.; Dye, R.H.; Neutzel, J.M.; Aronow, H.

    1977-03-01

    In an earlier paper, we examined the distribution of binaural resolvings power by measuring threshold increments of interaural delay as a function of overall delay (E. R. Hafter and J. Demaio, J. Acoust. Soc. Am. 57, 181--187 (1975)). In the current study, similar measures were made for interaural increments of intensity. As before, the stimuli were bandpass clicks of either low (0. 1--2 kHz) or higsh (3--4 kHz) frequency. For overall interaural differences as great as 24 dB, it seems that performance was based on the interaural differences, and not on the monaural increments/decrements that are concommitant with a binaural change in level. As was the case with time, sensitivity to interaural intensity was reasonably constant across the range tested; thus unlike the case for vision, spatial resolution in the auditory system is not concentrated in the center. A simple binaural trading ratio which converts intensity to time can be shown to fit the data for low-frequency clicks quite well. However, the fit to high frequencies is so poor as to suggest that separate mechanisms were used for detecting time and intensity. Finally, a number like the binaural masking-level difference (MLD) was computed for the two kinds of clicks. Surprisingly, the MLD's for low and high frequencies were a similar 7.2 and 8.0 dB.

  8. Early hominin auditory capacities.

    Science.gov (United States)

    Quam, Rolf; Martínez, Ignacio; Rosa, Manuel; Bonmatí, Alejandro; Lorenzo, Carlos; de Ruiter, Darryl J; Moggi-Cecchi, Jacopo; Conde Valverde, Mercedes; Jarabo, Pilar; Menter, Colin G; Thackeray, J Francis; Arsuaga, Juan Luis

    2015-09-01

    Studies of sensory capacities in past life forms have offered new insights into their adaptations and lifeways. Audition is particularly amenable to study in fossils because it is strongly related to physical properties that can be approached through their skeletal structures. We have studied the anatomy of the outer and middle ear in the early hominin taxa Australopithecus africanus and Paranthropus robustus and estimated their auditory capacities. Compared with chimpanzees, the early hominin taxa are derived toward modern humans in their slightly shorter and wider external auditory canal, smaller tympanic membrane, and lower malleus/incus lever ratio, but they remain primitive in the small size of their stapes footplate. Compared with chimpanzees, both early hominin taxa show a heightened sensitivity to frequencies between 1.5 and 3.5 kHz and an occupied band of maximum sensitivity that is shifted toward slightly higher frequencies. The results have implications for sensory ecology and communication, and suggest that the early hominin auditory pattern may have facilitated an increased emphasis on short-range vocal communication in open habitats.

  9. Early hominin auditory capacities

    Science.gov (United States)

    Quam, Rolf; Martínez, Ignacio; Rosa, Manuel; Bonmatí, Alejandro; Lorenzo, Carlos; de Ruiter, Darryl J.; Moggi-Cecchi, Jacopo; Conde Valverde, Mercedes; Jarabo, Pilar; Menter, Colin G.; Thackeray, J. Francis; Arsuaga, Juan Luis

    2015-01-01

    Studies of sensory capacities in past life forms have offered new insights into their adaptations and lifeways. Audition is particularly amenable to study in fossils because it is strongly related to physical properties that can be approached through their skeletal structures. We have studied the anatomy of the outer and middle ear in the early hominin taxa Australopithecus africanus and Paranthropus robustus and estimated their auditory capacities. Compared with chimpanzees, the early hominin taxa are derived toward modern humans in their slightly shorter and wider external auditory canal, smaller tympanic membrane, and lower malleus/incus lever ratio, but they remain primitive in the small size of their stapes footplate. Compared with chimpanzees, both early hominin taxa show a heightened sensitivity to frequencies between 1.5 and 3.5 kHz and an occupied band of maximum sensitivity that is shifted toward slightly higher frequencies. The results have implications for sensory ecology and communication, and suggest that the early hominin auditory pattern may have facilitated an increased emphasis on short-range vocal communication in open habitats. PMID:26601261

  10. The role of auditory abilities in basic mechanisms of cognition in older adults

    Directory of Open Access Journals (Sweden)

    Massimo eGrassi

    2013-10-01

    Full Text Available The aim of this study was to assess age-related differences between young and older adults in auditory abilities and to investigate the relationship between auditory abilities and basic mechanisms of cognition in older adults. Although there is a certain consensus that the participant’s sensitivity to the absolute intensity of sounds (such as that measured via pure tone audiometry explains his/her cognitive performance, there is not yet much evidence that the participant’s auditory ability (i.e., the whole supra-threshold processing of sounds explains his/her cognitive performance. Twenty-eight young adults (age < 35, 26 young-old adults (65 ≤ age ≤75 and 28 old-old adults (age > 75 were presented with a set of tasks estimating several auditory abilities (i.e., frequency discrimination, intensity discrimination, duration discrimination, timbre discrimination, gap detection, amplitude modulation detection, and the absolute threshold for a 1 kHz pure tone and the participant’s working memory, cognitive inhibition, and processing speed. Results showed an age-related decline in both auditory and cognitive performance. Moreover, regression analyses showed that a subset of the auditory abilities (i.e., the ability to discriminate frequency, duration, timbre, and the ability to detect amplitude modulation explained a significant part of the variance observed in processing speed in older adults. Overall, the present results highlight the relationship between auditory abilities and basic mechanisms of cognition.

  11. Brainstem auditory evoked potentials in children with lead exposure

    Directory of Open Access Journals (Sweden)

    Katia de Freitas Alvarenga

    2015-02-01

    Full Text Available Introduction: Earlier studies have demonstrated an auditory effect of lead exposure in children, but information on the effects of low chronic exposures needs to be further elucidated. Objective: To investigate the effect of low chronic exposures of the auditory system in children with a history of low blood lead levels, using an auditory electrophysiological test. Methods: Contemporary cross-sectional cohort. Study participants underwent tympanometry, pure tone and speech audiometry, transient evoked otoacoustic emissions, and brainstem auditory evoked potentials, with blood lead monitoring over a period of 35.5 months. The study included 130 children, with ages ranging from 18 months to 14 years, 5 months (mean age 6 years, 8 months ± 3 years, 2 months. Results: The mean time-integrated cumulative blood lead index was 12 µg/dL (SD ± 5.7, range:2.433. All participants had hearing thresholds equal to or below 20 dBHL and normal amplitudes of transient evoked otoacoustic emissions. No association was found between the absolute latencies of waves I, III, and V, the interpeak latencies I-III, III-V, and I-V, and the cumulative lead values. Conclusion: No evidence of toxic effects from chronic low lead exposures was observed on the auditory function of children living in a lead contaminated area.

  12. Brainstem auditory evoked potentials in children with lead exposure.

    Science.gov (United States)

    Alvarenga, Katia de Freitas; Morata, Thais Catalani; Lopes, Andrea Cintra; Feniman, Mariza Ribeiro; Corteletti, Lilian Cassia Bornia Jacob

    2015-01-01

    Earlier studies have demonstrated an auditory effect of lead exposure in children, but information on the effects of low chronic exposures needs to be further elucidated. To investigate the effect of low chronic exposures of the auditory system in children with a history of low blood lead levels, using an auditory electrophysiological test. Contemporary cross-sectional cohort. Study participants underwent tympanometry, pure tone and speech audiometry, transient evoked otoacoustic emissions, and brainstem auditory evoked potentials, with blood lead monitoring over a period of 35.5 months. The study included 130 children, with ages ranging from 18 months to 14 years, 5 months (mean age 6 years, 8 months ± 3 years, 2 months). The mean time-integrated cumulative blood lead index was 12 μg/dL (SD ± 5.7, range: 2.433). All participants had hearing thresholds equal to or below 20 dBHL and normal amplitudes of transient evoked otoacoustic emissions. No association was found between the absolute latencies of waves I, III, and V, the interpeak latencies I-III, III-V, and I-V, and the cumulative lead values. No evidence of toxic effects from chronic low lead exposures was observed on the auditory function of children living in a lead contaminated area. Copyright © 2014 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  13. Auditory Temporal Processing Abilities in Early Azari-Persian Bilinguals

    Directory of Open Access Journals (Sweden)

    Roya Sanayi

    2013-10-01

    Full Text Available Introduction: Auditory temporal resolution and auditory temporal ordering are two major components of the auditory temporal processing abilities that contribute to speech perception and language development. Auditory temporal resolution and auditory temporal ordering can be evaluated by gap-in-noise (GIN and pitch-pattern-sequence (PPS tests, respectively. In this survey, the effect of bilingualism as a potential confounding factor on auditory temporal processing abilities was investigated in early Azari-Persian bilinguals.   Materials and Methods:                                     In this cross-sectional non-interventional study, GIN and PPS tests were performed on 24 (12 men and 12 women early Azari-Persian bilingual persons and 24 (12 men and 12 women Persian monolingual subjects in the age range of 18–30 years, with a mean age of 24.57 years in bilingual and 24.68 years in monolingual subjects. Data were analyzed with t-test using SPSS software version 16.   Results: There was no statistically significant difference between mean gap threshold and mean percentages of the correct response of the GIN test and average percentage of correct responses in the PPS test between early Azari-Persian bilinguals and Persian monolinguals (P≥0.05.   Conclusion:  According to the findings of this study, bilingualism did not have notable effect on auditory temporal processing abilities.

  14. Auditory Perceptual Abilities Are Associated with Specific Auditory Experience

    Directory of Open Access Journals (Sweden)

    Yael Zaltz

    2017-11-01

    Full Text Available The extent to which auditory experience can shape general auditory perceptual abilities is still under constant debate. Some studies show that specific auditory expertise may have a general effect on auditory perceptual abilities, while others show a more limited influence, exhibited only in a relatively narrow range associated with the area of expertise. The current study addresses this issue by examining experience-dependent enhancement in perceptual abilities in the auditory domain. Three experiments were performed. In the first experiment, 12 pop and rock musicians and 15 non-musicians were tested in frequency discrimination (DLF, intensity discrimination, spectrum discrimination (DLS, and time discrimination (DLT. Results showed significant superiority of the musician group only for the DLF and DLT tasks, illuminating enhanced perceptual skills in the key features of pop music, in which miniscule changes in amplitude and spectrum are not critical to performance. The next two experiments attempted to differentiate between generalization and specificity in the influence of auditory experience, by comparing subgroups of specialists. First, seven guitar players and eight percussionists were tested in the DLF and DLT tasks that were found superior for musicians. Results showed superior abilities on the DLF task for guitar players, though no difference between the groups in DLT, demonstrating some dependency of auditory learning on the specific area of expertise. Subsequently, a third experiment was conducted, testing a possible influence of vowel density in native language on auditory perceptual abilities. Ten native speakers of German (a language characterized by a dense vowel system of 14 vowels, and 10 native speakers of Hebrew (characterized by a sparse vowel system of five vowels, were tested in a formant discrimination task. This is the linguistic equivalent of a DLS task. Results showed that German speakers had superior formant

  15. Sound stimulation and its effect on dental sensation threshold.

    Science.gov (United States)

    CARLIN, S; WARD, W D; GERSHON, A; INGRAHAM, R

    1962-12-14

    The success of "auditory analgesia" in dental operations may be a result of distraction, suggestion, or cross-sensory masking, or of a combination of the three. An attempt to separate these influences was made by measuring the change in sensitivity to electrical stimulation of the teeth in typical dental patients upon presentation of loud white noise. No differences in this "tingle" threshold under noise and no-noise conditions were found, either when preliminary instructions were neutral or after implicit or explicit suggestion that the noise would raise the threshold. These results indicate that auditory analgesia is probably not an example of cross-sensory masking, and that its successful use in the clinical situation depends both on distraction and on suggestion.

  16. Threshold Concepts in Economics

    Science.gov (United States)

    Shanahan, Martin

    2016-01-01

    Purpose: The purpose of this paper is to examine threshold concepts in the context of teaching and learning first-year university economics. It outlines some of the arguments for using threshold concepts and provides examples using opportunity cost as an exemplar in economics. Design/ Methodology/Approach: The paper provides an overview of the…

  17. Auditory Discrimination and Auditory Sensory Behaviours in Autism Spectrum Disorders

    Science.gov (United States)

    Jones, Catherine R. G.; Happe, Francesca; Baird, Gillian; Simonoff, Emily; Marsden, Anita J. S.; Tregay, Jenifer; Phillips, Rebecca J.; Goswami, Usha; Thomson, Jennifer M.; Charman, Tony

    2009-01-01

    It has been hypothesised that auditory processing may be enhanced in autism spectrum disorders (ASD). We tested auditory discrimination ability in 72 adolescents with ASD (39 childhood autism; 33 other ASD) and 57 IQ and age-matched controls, assessing their capacity for successful discrimination of the frequency, intensity and duration…

  18. Auditory and non-auditory effects of noise on health

    NARCIS (Netherlands)

    Basner, M.; Babisch, W.; Davis, A.; Brink, M.; Clark, C.; Janssen, S.A.; Stansfeld, S.

    2013-01-01

    Noise is pervasive in everyday life and can cause both auditory and non-auditory health eff ects. Noise-induced hearing loss remains highly prevalent in occupational settings, and is increasingly caused by social noise exposure (eg, through personal music players). Our understanding of molecular

  19. The Central Auditory Processing Kit[TM]. Book 1: Auditory Memory [and] Book 2: Auditory Discrimination, Auditory Closure, and Auditory Synthesis [and] Book 3: Auditory Figure-Ground, Auditory Cohesion, Auditory Binaural Integration, and Compensatory Strategies.

    Science.gov (United States)

    Mokhemar, Mary Ann

    This kit for assessing central auditory processing disorders (CAPD), in children in grades 1 through 8 includes 3 books, 14 full-color cards with picture scenes, and a card depicting a phone key pad, all contained in a sturdy carrying case. The units in each of the three books correspond with auditory skill areas most commonly addressed in…

  20. Polarity-Specific Transcranial Direct Current Stimulation Disrupts Auditory Pitch Learning

    Directory of Open Access Journals (Sweden)

    Reiko eMatsushita

    2015-05-01

    Full Text Available Transcranial direct current stimulation (tDCS is attracting increasing interest because of its potential for therapeutic use. While its effects have been investigated mainly with motor and visual tasks, less is known in the auditory domain. Past tDCS studies with auditory tasks demonstrated various behavioural outcomes, possibly due to differences in stimulation parameters or task measurements used in each study. Further research using well-validated tasks are therefore required for clarification of behavioural effects of tDCS on the auditory system. Here, we took advantage of findings from a prior functional magnetic resonance imaging study, which demonstrated that the right auditory cortex is modulated during fine-grained pitch learning of microtonal melodic patterns. Targeting the right auditory cortex with tDCS using this same task thus allowed us to test the hypothesis that this region is causally involved in pitch learning. Participants in the current study were trained for three days while we measured pitch discrimination thresholds using microtonal melodies on each day using a psychophysical staircase procedure. We administered anodal, cathodal, or sham tDCS to three groups of participants over the right auditory cortex on the second day of training during performance of the task. Both the sham and the cathodal groups showed the expected significant learning effect (decreased pitch threshold over the three days of training; in contrast we observed a blocking effect of anodal tDCS on auditory pitch learning, such that this group showed no significant change in thresholds over the three days. The results support a causal role for the right auditory cortex in pitch discrimination learning.

  1. The dissimilar time course of temporary threshold shifts and reduction of inhibition in the inferior colliculus following intense sound exposure

    NARCIS (Netherlands)

    Heeringa, A. N.; van Dijk, P.

    Excessive noise exposure is known to produce an auditory threshold shift, which can be permanent or transient in nature. Recent studies showed that noise-induced temporary threshold shifts are associated with loss of synaptic connections to the inner hair cells and with cochlear nerve degeneration,

  2. Threshold concepts in prosthetics.

    Science.gov (United States)

    Hill, Sophie

    2017-12-01

    Curriculum documents identify key concepts within learning prosthetics. Threshold concepts provide an alternative way of viewing the curriculum, focussing on the ways of thinking and practicing within prosthetics. Threshold concepts can be described as an opening to a different way of viewing a concept. This article forms part of a larger study exploring what students and staff experience as difficult in learning about prosthetics. To explore possible threshold concepts within prosthetics. Qualitative, interpretative phenomenological analysis. Data from 18 students and 8 staff at two universities with undergraduate prosthetics and orthotics programmes were generated through interviews and questionnaires. The data were analysed using an interpretative phenomenological analysis approach. Three possible threshold concepts arose from the data: 'how we walk', 'learning to talk' and 'considering the person'. Three potential threshold concepts in prosthetics are suggested with possible implications for prosthetics education. These possible threshold concepts involve changes in both conceptual and ontological knowledge, integrating into the persona of the individual. This integration occurs through the development of memories associated with procedural concepts that combine with disciplinary concepts. Considering the prosthetics curriculum through the lens of threshold concepts enables a focus on how students learn to become prosthetists. Clinical relevance This study provides new insights into how prosthetists learn. This has implications for curriculum design in prosthetics education.

  3. Partial Epilepsy with Auditory Features

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2004-07-01

    Full Text Available The clinical characteristics of 53 sporadic (S cases of idiopathic partial epilepsy with auditory features (IPEAF were analyzed and compared to previously reported familial (F cases of autosomal dominant partial epilepsy with auditory features (ADPEAF in a study at the University of Bologna, Italy.

  4. The Perception of Auditory Motion

    Science.gov (United States)

    Leung, Johahn

    2016-01-01

    The growing availability of efficient and relatively inexpensive virtual auditory display technology has provided new research platforms to explore the perception of auditory motion. At the same time, deployment of these technologies in command and control as well as in entertainment roles is generating an increasing need to better understand the complex processes underlying auditory motion perception. This is a particularly challenging processing feat because it involves the rapid deconvolution of the relative change in the locations of sound sources produced by rotational and translations of the head in space (self-motion) to enable the perception of actual source motion. The fact that we perceive our auditory world to be stable despite almost continual movement of the head demonstrates the efficiency and effectiveness of this process. This review examines the acoustical basis of auditory motion perception and a wide range of psychophysical, electrophysiological, and cortical imaging studies that have probed the limits and possible mechanisms underlying this perception. PMID:27094029

  5. Peripheral Auditory Mechanisms

    CERN Document Server

    Hall, J; Hubbard, A; Neely, S; Tubis, A

    1986-01-01

    How weIl can we model experimental observations of the peripheral auditory system'? What theoretical predictions can we make that might be tested'? It was with these questions in mind that we organized the 1985 Mechanics of Hearing Workshop, to bring together auditory researchers to compare models with experimental observations. Tbe workshop forum was inspired by the very successful 1983 Mechanics of Hearing Workshop in Delft [1]. Boston University was chosen as the site of our meeting because of the Boston area's role as a center for hearing research in this country. We made a special effort at this meeting to attract students from around the world, because without students this field will not progress. Financial support for the workshop was provided in part by grant BNS- 8412878 from the National Science Foundation. Modeling is a traditional strategy in science and plays an important role in the scientific method. Models are the bridge between theory and experiment. Tbey test the assumptions made in experim...

  6. Regional Seismic Threshold Monitoring

    National Research Council Canada - National Science Library

    Kvaerna, Tormod

    2006-01-01

    ... model to be used for predicting the travel times of regional phases. We have applied these attenuation relations to develop and assess a regional threshold monitoring scheme for selected subregions of the European Arctic...

  7. Auditory Training Effects on the Listening Skills of Children With Auditory Processing Disorder.

    Science.gov (United States)

    Loo, Jenny Hooi Yin; Rosen, Stuart; Bamiou, Doris-Eva

    2016-01-01

    Children with auditory processing disorder (APD) typically present with "listening difficulties,"' including problems understanding speech in noisy environments. The authors examined, in a group of such children, whether a 12-week computer-based auditory training program with speech material improved the perception of speech-in-noise test performance, and functional listening skills as assessed by parental and teacher listening and communication questionnaires. The authors hypothesized that after the intervention, (1) trained children would show greater improvements in speech-in-noise perception than untrained controls; (2) this improvement would correlate with improvements in observer-rated behaviors; and (3) the improvement would be maintained for at least 3 months after the end of training. This was a prospective randomized controlled trial of 39 children with normal nonverbal intelligence, ages 7 to 11 years, all diagnosed with APD. This diagnosis required a normal pure-tone audiogram and deficits in at least two clinical auditory processing tests. The APD children were randomly assigned to (1) a control group that received only the current standard treatment for children diagnosed with APD, employing various listening/educational strategies at school (N = 19); or (2) an intervention group that undertook a 3-month 5-day/week computer-based auditory training program at home, consisting of a wide variety of speech-based listening tasks with competing sounds, in addition to the current standard treatment. All 39 children were assessed for language and cognitive skills at baseline and on three outcome measures at baseline and immediate postintervention. Outcome measures were repeated 3 months postintervention in the intervention group only, to assess the sustainability of treatment effects. The outcome measures were (1) the mean speech reception threshold obtained from the four subtests of the listening in specialized noise test that assesses sentence perception in

  8. Threshold concepts in prosthetics

    OpenAIRE

    Hill, Sophie

    2016-01-01

    Background: Curriculum documents identify key concepts within learning prosthetics. Threshold concepts provide an alternative way of viewing the curriculum, focussing on the ways of thinking and practicing within prosthetics. Threshold concepts can be described as an opening to a different way of viewing a concept. This article forms part of a larger study exploring what students and staff experience as difficult in learning about prosthetics. Objectives: To explore possible thresh...

  9. Effects of Noise Exposure on the Auditory Function of Ovariectomized Rats with Estrogen Deficiency.

    Science.gov (United States)

    Hu, Xujun; Wang, Ying; Lau, Chi Chuen

    2016-12-01

    The benefits of estrogen for the auditory function of women depend on a number of factors. In this study, we aimed to examine the impact of noise trauma on the auditory function of ovariectomized rats with estrogen deficiency. Twenty-eight young, female Sprague-Dawley rats were assigned to three groups (OVX+N, OVX-N, Sham+N). Rats in the OVX+N group and the OVX-N group underwent bilateral ovariectomy (OVX); the OVX+N group alone was also exposed to white noise (N) of 115 dB SPL for 8 hours a day over 14 days. The Sham+N group consisted of rats with intact ovaries that were exposed to the same noise. The auditory function of all rats was measured before treatment and after noise exposure by the signal-to-noise ratio (SNR) of distortion-product otoacoustic emissions (DPOAE) and the threshold of auditory-evoked brainstem response (ABR). The Sham+N group (intact ovaries, noise-exposed) had worse auditory function than the OVX-N group (ovariectomy, no noise). The OVX+N group had decreased SNRs of DPOAE and increased ABR thresholds relative to the Sham+N group. Noise exposure may cause greater damage to auditory function when estrogen levels are low in females.

  10. Age-related dissociation of sensory and decision-based auditory motion processing

    Directory of Open Access Journals (Sweden)

    Alexandra Annemarie Ludwig

    2012-03-01

    Full Text Available Studies on the maturation of auditory motion processing in children have yielded inconsistent reports. The present study combines subjective and objective measurements to investigate how the auditory perceptual abilities of children change during development and whether these changes are paralleled by changes in the event-related brain potential (ERP.We employed the mismatch negativity (MMN to determine maturational changes in the discrimination of interaural time differences (ITD that generate lateralized moving auditory percepts. MMNs were elicited in children, teenagers, and adults, using a small and a large ITD at stimulus offset with respect to each subject’s discrimination threshold. In adults and teenagers large deviants elicited prominent MMNs, whereas small deviants at the behavioral threshold elicited only a marginal or no MMN. In contrast, pronounced MMNs for both deviant sizes were found in children. Behaviourally, however, most of the children showed higher discrimination thresholds than teens and adults.Although automatic ITD detection is functional, active discrimination is still limited in children. The lack of MMN deviance dependency in children suggests that unlike in teenagers and adults, neural signatures of automatic auditory motion processing do not mirror discrimination abilities.The study critically accounts for advanced understanding of children’s central auditory development.

  11. A Comparison of Auditory Perception in Hearing-Impaired and Normal-Hearing Listeners: An Auditory Scene Analysis Study

    Science.gov (United States)

    Bayat, Arash; Farhadi, Mohammad; Pourbakht, Akram; Sadjedi, Hamed; Emamdjomeh, Hesam; Kamali, Mohammad; Mirmomeni, Golshan

    2013-01-01

    Background Auditory scene analysis (ASA) is the process by which the auditory system separates individual sounds in natural-world situations. ASA is a key function of auditory system, and contributes to speech discrimination in noisy backgrounds. It is known that sensorineural hearing loss (SNHL) detrimentally affects auditory function in complex environments, but relatively few studies have focused on the influence of SNHL on higher level processes which are likely involved in auditory perception in different situations. Objectives The purpose of the current study was to compare the auditory system ability of normally hearing and SNHL subjects using the ASA examination. Materials and Methods A total of 40 right-handed adults (age range: 18 - 45 years) participated in this study. The listeners were divided equally into control and mild to moderate SNHL groups. ASA ability was measured using an ABA-ABA sequence. The frequency of the "A" was kept constant at 500, 1000, 2000 or 4000 Hz, while the frequency of the "B" was set at 3 to 80 percent above the" A" tone. For ASA threshold detection, the frequency of the B stimulus was decreased until listeners reported that they could no longer hear two separate sounds. Results The ASA performance was significantly better for controls than the SNHL group; these differences were more obvious at higher frequencies. We found no significant differences between ASA ability as a function of tone durations in both groups. Conclusions The present study indicated that SNHL may cause a reduction in perceptual separation of the incoming acoustic information to form accurate representations of our acoustic world. PMID:24719695

  12. Auditory hallucinations treated by radio headphones.

    Science.gov (United States)

    Feder, R

    1982-09-01

    A young man with chronic auditory hallucinations was treated according to the principle that increasing external auditory stimulation decreases the likelihood of auditory hallucinations. Listening to a radio through stereo headphones in conditions of low auditory stimulation eliminated the patient's hallucinations.

  13. Auditory-steady-state response reliability in the audiological diagnosis after neonatal hearing screening.

    Science.gov (United States)

    Núñez-Batalla, Faustino; Noriega-Iglesias, Sabel; Guntín-García, Maite; Carro-Fernández, Pilar; Llorente-Pendás, José Luis

    2016-01-01

    Conventional audiometry is the gold standard for quantifying and describing hearing loss. Alternative methods become necessary to assess subjects who are too young to respond reliably. Auditory evoked potentials constitute the most widely used method for determining hearing thresholds objectively; however, this stimulus is not frequency specific. The advent of the auditory steady-state response (ASSR) leads to more specific threshold determination. The current study describes and compares ASSR, auditory brainstem response (ABR) and conventional behavioural tone audiometry thresholds in a group of infants with various degrees of hearing loss. A comparison was made between ASSR, ABR and behavioural hearing thresholds in 35 infants detected in the neonatal hearing screening program. Mean difference scores (±SD) between ABR and high frequency ABR thresholds were 11.2 dB (±13) and 10.2 dB (±11). Pearson correlations between the ASSR and audiometry thresholds were 0.80 and 0.91 (500Hz); 0.84 and 0.82 (1000Hz); 0.85 and 0.84 (2000Hz); and 0.83 and 0.82 (4000Hz). The ASSR technique is a valuable extension of the clinical test battery for hearing-impaired children. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

  14. The auditory brainstem response of aged guinea pigs.

    Science.gov (United States)

    Ingham, N J; Thornton, S K; Comis, S D; Withington, D J

    1998-09-01

    The auditory brainstem response (ABR) technique was used to investigate potential dysfunctions in the auditory brainstem of the pigmented guinea pig (Cavia porcellus) associated with biological ageing. Animals aged from 58 days to 4 years 3 months were tested. ABRs were recorded at stimulation intensities from 85 dB HL to -10 dB HL. The auditory thresholds were found to undergo marked elevations in old animals, by an average of 32 dB. From the traces obtained, four positive deflection waves were reliably recorded. The latency of each of the four waves was evaluated at different stimulation intensities in guinea pigs of different ages. Although there was a trend for the latencies to increase in old age, these differences were not statistically significant. Similarly, there were no significant age-related changes in the inter-peak intervals. The latency/intensity functions of the four waves produced parallel curves. However, the curve from the old age group was shifted to the right, by an average of 35 dB, indicative of conductive hearing loss. There was no evidence of retro-cochlear hearing loss. Therefore, it appears that the threshold elevations in the old animals can be accounted for by conductive hearing loss, presumably in the middle ear. In 24% of the old animals tested, no ABR could be elicited. It would appear that these animals had suffered severe sensorineural hearing loss.

  15. Auditory processing in children with language-based learning problems: a magnetencephalography study.

    Science.gov (United States)

    Diedler, Jennifer; Pietz, Joachim; Brunner, Monika; Hornberger, Cornelia; Bast, Thomas; Rupp, André

    2009-06-17

    We examined basic auditory temporal processing in children with language-based learning problems (LPs) applying magnetencephalography. Auditory-evoked fields of 43 children (27 LP, 16 controls) were recorded while passively listening to 100-ms white noise bursts with temporal gaps of 3, 6, 10 and 30 ms inserted after 5 or 50 ms. The P1m was evaluated by spatio-temporal source analysis. Psychophysical gap-detection thresholds were obtained for the same participants. Thirty-two percent of the LP children were not able to perform the early gap psychoacoustic task. In addition, LP children displayed a significant delay of the P1m during the early gap task. These findings provide evidence for a diminished neuronal representation of short auditory stimuli in the primary auditory cortex of LP children.

  16. Experience-dependent learning of auditory temporal resolution: evidence from Carnatic-trained musicians.

    Science.gov (United States)

    Mishra, Srikanta K; Panda, Manasa R

    2014-01-22

    Musical training and experience greatly enhance the cortical and subcortical processing of sounds, which may translate to superior auditory perceptual acuity. Auditory temporal resolution is a fundamental perceptual aspect that is critical for speech understanding in noise in listeners with normal hearing, auditory disorders, cochlear implants, and language disorders, yet very few studies have focused on music-induced learning of temporal resolution. This report demonstrates that Carnatic musical training and experience have a significant impact on temporal resolution assayed by gap detection thresholds. This experience-dependent learning in Carnatic-trained musicians exhibits the universal aspects of human perception and plasticity. The present work adds the perceptual component to a growing body of neurophysiological and imaging studies that suggest plasticity of the peripheral auditory system at the level of the brainstem. The present work may be intriguing to researchers and clinicians alike interested in devising cross-cultural training regimens to alleviate listening-in-noise difficulties.

  17. [The influence of external factors on the auditory function in the students residing in a megapolis].

    Science.gov (United States)

    Levina, Iu V; Kudeeva, Ia Iu; Ibragimov, Sh I

    2013-01-01

    The objective of the present study was to estimate the auditory function in the students aged from 20 to 30 years and the noise load associated with the use of mobile phones, listening to music through headphones, attending concerts and youth clubs. The secondary objective was to assess the influence of these factors on the auditory function depending on their type, intensity, and duration. It is shown that the auditory threshold in the frequency range between 125 and 8000 Hz in 97% of the examined students do not exceed 25 dB varying from 5 to 15 dB The main factor influencing the auditory function is the use of players and headphones followed by mobile phones and deafening music in youth clubs.

  18. Auditory short-term memory in the primate auditory cortex.

    Science.gov (United States)

    Scott, Brian H; Mishkin, Mortimer

    2016-06-01

    Sounds are fleeting, and assembling the sequence of inputs at the ear into a coherent percept requires auditory memory across various time scales. Auditory short-term memory comprises at least two components: an active ׳working memory' bolstered by rehearsal, and a sensory trace that may be passively retained. Working memory relies on representations recalled from long-term memory, and their rehearsal may require phonological mechanisms unique to humans. The sensory component, passive short-term memory (pSTM), is tractable to study in nonhuman primates, whose brain architecture and behavioral repertoire are comparable to our own. This review discusses recent advances in the behavioral and neurophysiological study of auditory memory with a focus on single-unit recordings from macaque monkeys performing delayed-match-to-sample (DMS) tasks. Monkeys appear to employ pSTM to solve these tasks, as evidenced by the impact of interfering stimuli on memory performance. In several regards, pSTM in monkeys resembles pitch memory in humans, and may engage similar neural mechanisms. Neural correlates of DMS performance have been observed throughout the auditory and prefrontal cortex, defining a network of areas supporting auditory STM with parallels to that supporting visual STM. These correlates include persistent neural firing, or a suppression of firing, during the delay period of the memory task, as well as suppression or (less commonly) enhancement of sensory responses when a sound is repeated as a ׳match' stimulus. Auditory STM is supported by a distributed temporo-frontal network in which sensitivity to stimulus history is an intrinsic feature of auditory processing. This article is part of a Special Issue entitled SI: Auditory working memory. Published by Elsevier B.V.

  19. Auditory-olfactory synesthesia coexisting with auditory-visual synesthesia.

    Science.gov (United States)

    Jackson, Thomas E; Sandramouli, Soupramanien

    2012-09-01

    Synesthesia is an unusual condition in which stimulation of one sensory modality causes an experience in another sensory modality or when a sensation in one sensory modality causes another sensation within the same modality. We describe a previously unreported association of auditory-olfactory synesthesia coexisting with auditory-visual synesthesia. Given that many types of synesthesias involve vision, it is important that the clinician provide these patients with the necessary information and support that is available.

  20. Selective Auditory Attention in Adults: Effects of Rhythmic Structure of the Competing Language

    Science.gov (United States)

    Reel, Leigh Ann; Hicks, Candace Bourland

    2012-01-01

    Purpose: The authors assessed adult selective auditory attention to determine effects of (a) differences between the vocal/speaking characteristics of different mixed-gender pairs of masking talkers and (b) the rhythmic structure of the language of the competing speech. Method: Reception thresholds for English sentences were measured for 50…

  1. Auditory Processing Training in Learning Disability

    OpenAIRE

    Nívea Franklin Chaves Martins; Hipólito Virgílio Magalhães Jr

    2006-01-01

    The aim of this case report was to promote a reflection about the importance of speech-therapy for stimulation a person with learning disability associated to language and auditory processing disorders. Data analysis considered the auditory abilities deficits identified in the first auditory processing test, held on April 30,2002 compared with the new auditory processing test done on May 13,2003,after one year of therapy directed to acoustic stimulation of auditory abilities disorders,in acco...

  2. Deficit of auditory temporal processing in children with dyslexia-dysgraphia

    Directory of Open Access Journals (Sweden)

    Sima Tajik

    2012-12-01

    Full Text Available Background and Aim: Auditory temporal processing reveals an important aspect of auditory performance, in which a deficit can prevent the child from speaking, language learning and reading. Temporal resolution, which is a subgroup of temporal processing, can be evaluated by gap-in-noise detection test. Regarding the relation of auditory temporal processing deficits and phonologic disorder of children with dyslexia-dysgraphia, the aim of this study was to evaluate these children with the gap-in-noise (GIN test.Methods: The gap-in-noise test was performed on 28 normal and 24 dyslexic-dysgraphic children, at the age of 11-12 years old. Mean approximate threshold and percent of corrected answers were compared between the groups.Results: The mean approximate threshold and percent of corrected answers of the right and left ear had no significant difference between the groups (p>0.05. The mean approximate threshold of children with dyslexia-dysgraphia (6.97 ms, SD=1.09 was significantly (p<0.001 more than that of the normal group (5.05 ms, SD=0.92. The mean related frequency of corrected answers (58.05, SD=4.98% was less than normal group (69.97, SD=7.16% (p<0.001.Conclusion: Abnormal temporal resolution was found in children with dyslexia-dysgraphia based on gap-in-noise test. While the brainstem and auditory cortex are responsible for auditory temporal processing, probably the structural and functional differences of these areas in normal and dyslexic-dysgraphic children lead to abnormal coding of auditory temporal information. As a result, auditory temporal processing is inevitable.

  3. Similar structural dimensions in bushcricket auditory organs in spite of different foreleg size: consequences for auditory tuning.

    Science.gov (United States)

    Rössler, W; Kalmring, K

    1994-11-01

    The bushcricket species Decticus albifrons, Decticus verrucivorus and Pholidoptera griseoaptera (Tettigoniidae) belong to the same subfamily (Decticinae) but differ significantly in body size. In spite of the great differences in the dimensions of the forelegs, where the auditory organs are located, the most sensitive range of the hearing threshold lies between 6 and 25 kHz in each case. Only in the frequency range from 2 to 5 kHz and above 25 kHz, significant differences are present. The anatomy of the auditory receptor organs was compared quantitatively, using the techniques of semi-thin sectioning and computer-guided morphometry. The overall number of scolopidia and the length of the crista acustica differs in the three species, but the relative distribution of scolopidia along the crista acustica is very similar. Additionally, the scolopidia and their attachment structures (tectorial membrane, dorsal tracheal wall, cap cells) are of equal size at equivalent relative positions along the crista acustica. The results indicate that the constant relations and dimensions of corresponding structures within the cristae acusticae of the three species are responsible for the similarities in the tuning of the auditory thresholds.

  4. Cortical Evoked Potentials and Hearing Aids in Individuals with Auditory Dys-Synchrony.

    Science.gov (United States)

    Yuvaraj, Pradeep; Mannarukrishnaiah, Jayaram

    2015-12-01

    The purpose of the present study was to investigate the relationship between cortical processing of speech and benefit from hearing aids in individuals with auditory dys-synchrony. Data were collected from 38 individuals with auditory dys-synchrony. Participants were selected based on hearing thresholds, middle ear reflexes, otoacoustic emissions, and auditory brain stem responses. Cortical-evoked potentials were recorded for click and speech. Participants with auditory dys-synchrony were fitted with bilateral multichannel wide dynamic range compression hearing aids. Aided and unaided speech identification scores for 40 words were obtained for each participant. Hierarchical cluster analysis using Ward's method clearly showed four subgroups of participants with auditory dys-synchrony based on the hearing aid benefit score (aided minus unaided speech identification score). The difference in the mean aided and unaided speech identification scores was significantly different in participants with auditory dys-synchrony. However, the mean unaided speech identification scores were not significantly different between the four subgroups. The N2 amplitude and P1 latency of the speech-evoked cortical potentials were significantly different between the four subgroups formed based on hearing aid benefit scores. The results indicated that subgroups of individuals with auditory dys-synchrony who benefit from hearing aids exist. Individuals who benefitted from hearing aids showed decreased N2 amplitudes compared with those who did not. N2 amplitude is associated with greater suppression of background noise while processing speech.

  5. A visual or tactile signal makes auditory speech detection more efficient by reducing uncertainty.

    Science.gov (United States)

    Tjan, Bosco S; Chao, Ewen; Bernstein, Lynne E

    2014-04-01

    Acoustic speech is easier to detect in noise when the talker can be seen. This finding could be explained by integration of multisensory inputs or refinement of auditory processing from visual guidance. In two experiments, we studied two-interval forced-choice detection of an auditory 'ba' in acoustic noise, paired with various visual and tactile stimuli that were identically presented in the two observation intervals. Detection thresholds were reduced under the multisensory conditions vs. the auditory-only condition, even though the visual and/or tactile stimuli alone could not inform the correct response. Results were analysed relative to an ideal observer for which intrinsic (internal) noise and efficiency were independent contributors to detection sensitivity. Across experiments, intrinsic noise was unaffected by the multisensory stimuli, arguing against the merging (integrating) of multisensory inputs into a unitary speech signal, but sampling efficiency was increased to varying degrees, supporting refinement of knowledge about the auditory stimulus. The steepness of the psychometric functions decreased with increasing sampling efficiency, suggesting that the 'task-irrelevant' visual and tactile stimuli reduced uncertainty about the acoustic signal. Visible speech was not superior for enhancing auditory speech detection. Our results reject multisensory neuronal integration and speech-specific neural processing as explanations for the enhanced auditory speech detection under noisy conditions. Instead, they support a more rudimentary form of multisensory interaction: the otherwise task-irrelevant sensory systems inform the auditory system about when to listen. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  6. Auditory Distraction and Acclimatization to Hearing Aids.

    Science.gov (United States)

    Dawes, Piers; Munro, Kevin J

    It is widely recognized by hearing aid users and audiologists that a period of auditory acclimatization and adjustment is needed for new users to become accustomed to their devices. The aim of the present study was to test the idea that auditory acclimatization and adjustment to hearing aids involves a process of learning to "tune out" newly audible but undesirable sounds, which are described by new hearing aid users as annoying and distracting. It was hypothesized that (1) speech recognition thresholds in noise would improve over time for new hearing aid users, (2) distractibility to noise would reduce over time for new hearing aid users, (3) there would be a correlation between improved speech recognition in noise and reduced distractibility to background sounds, (4) improvements in speech recognition and distraction would be accompanied by self-report of reduced annoyance, and (5) improvements in speech recognition and distraction would be associated with higher general cognitive ability and more hearing aid use. New adult hearing aid users (n = 35) completed a test of aided speech recognition in noise (SIN) and a test of auditory distraction by background sound amplified by hearing aids on the day of fitting and 1, 7, 14, and 30 days post fitting. At day 30, participants completed self-ratings of the annoyance of amplified sounds. Daily hearing aid use was measured via hearing aid data logging, and cognitive ability was measured with the Wechsler Abbreviated Scale of Intelligence block design test. A control group of experienced hearing aid users (n = 20) completed the tests over a similar time frame. At day 30, there was no statistically significant improvement in SIN among new users versus experienced users. However, levels of hearing loss and hearing aid use varied widely among new users. A subset of new users with moderate hearing loss who wore their hearing aids at least 6 hr/day (n = 10) had significantly improved SIN (by ~3-dB signal to noise ratio

  7. Screening for auditory processing performance in primary school children.

    Science.gov (United States)

    Mourad, Mona; Hassan, Mona; El-Banna, Manal; Asal, Samir; Hamza, Yasmeen

    2015-04-01

    A deficit in the processing of auditory information may underlie problems in understanding speech in the presence of background noise, degraded speech, and in following spoken instructions. Children with auditory processing disorders are challenged in the classroom because of ambient noise levels and maybe at risk for learning disabilities. 1) Set up and execute screening protocol for auditory processing performance (APP) in primary school children. 2) Construct database for APP in the classroom. 3) Set critical limits for deviant performance. Our hypothesis is that screening for APP in the classroom identifies pupils at risk for auditory processing disorders. Study consisted of two phases. Phase 1: 2,015 pupils were selected from fourth-, fifth-, and sixth-graders using stratified random sampling with the proportional allocation method. Male and female students were equally represented. Otoscopic examination, screening audiometery, and screening tests for auditory processing (AP) abilities (Pitch Pattern Sequence Test [PPST], speech perception in noise [SPIN] right, SPIN left, and Dichotic Digit Test) were conducted. A questionnaire emphasizing auditory listening behaviors (ALB) was answered by classroom teacher. Phase 2 included 69 pupils who were randomly selected based on percentile scores of phase 1. Students were examined for the corresponding full version AP tests in addition to Auditory Fusion Test-Revised and masking level difference. Intelligence quotient and learning disabilities were evaluated. Phase 1: Results are displayed in frequency polygons for10th, 25th, 50th, 75th, and 90th percentiles score for each AP test. Fourth-graders scored significantly lower than fifth- and sixth-graders on all tests. Males scored lower than females on PPST. A composite score was calculated to represent a summed score performance for PPST, SPIN right ear, SPIN left ear, and Dichotic Digit Test. Scores Auditory Fusion Test-Revised mean thresholds were statistically

  8. Changes in auditory perceptions and cortex resulting from hearing recovery after extended congenital unilateral hearing loss

    Directory of Open Access Journals (Sweden)

    Jill B Firszt

    2013-12-01

    Full Text Available Monaural hearing induces auditory system reorganization. Imbalanced input also degrades time-intensity cues for sound localization and signal segregation for listening in noise. While there have been studies of bilateral auditory deprivation and later hearing restoration (e.g. cochlear implants, less is known about unilateral auditory deprivation and subsequent hearing improvement. We investigated effects of long-term congenital unilateral hearing loss on localization, speech understanding, and cortical organization following hearing recovery. Hearing in the congenitally affected ear of a 41 year old female improved significantly after stapedotomy and reconstruction. Pre-operative hearing threshold levels showed unilateral, mixed, moderately-severe to profound hearing loss. The contralateral ear had hearing threshold levels within normal limits. Testing was completed prior to, and three and nine months after surgery. Measurements were of sound localization with intensity-roved stimuli and speech recognition in various noise conditions. We also evoked magnetic resonance signals with monaural stimulation to the unaffected ear. Activation magnitudes were determined in core, belt, and parabelt auditory cortex regions via an interrupted single event design. Hearing improvement following 40 years of congenital unilateral hearing loss resulted in substantially improved sound localization and speech recognition in noise. Auditory cortex also reorganized. Contralateral auditory cortex responses were increased after hearing recovery and the extent of activated cortex was bilateral, including a greater portion of the posterior superior temporal plane. Thus, prolonged predominant monaural stimulation did not prevent auditory system changes consequent to restored binaural hearing. Results support future research of unilateral auditory deprivation effects and plasticity, with consideration for length of deprivation, age at hearing correction, degree and type

  9. Analysis of spectral shape in the barn owl auditory system.

    Science.gov (United States)

    Langemann, U; Zokoll, M A; Klump, G M

    2005-10-01

    In a behavioral experiment, we investigated how efficiently barn owls (Tyto alba) could detect changes in the spectral profile of multi-component auditory signals with stochastic envelope patterns. Signals consisted of one or five bands of noise (bandwidth 4, 16, or 64 Hz each; center frequencies 1.02, 1.43, 2.0, 2.8, 3.92 kHz). We determined increment thresholds for the 2 kHz component for three conditions: single-band condition (only the 2 kHz component), all five noise bands with the envelope fluctuations of the bands being either correlated or uncorrelated. Noise bandwidth had no significant effect on increment detection. Increment thresholds for the different conditions, however, differed significantly. Thresholds in correlated conditions were generally the lowest of all conditions, whereas, thresholds in uncorrelated conditions mostly resulted in the highest thresholds. This can be interpreted as evidence for comodulation masking release in barn owls. If the increment in the 2 kHz component is balanced by decrementing the four flanking bands in amplitude, increment detection thresholds are not affected. The data suggest that the barn owls used information from simultaneous spectral comparison across different frequency channels to detect spectral changes in multi-component noise signals rather than sequential comparison of overall stimulus levels.

  10. Long-Term Evolution of Brainstem Electrical Evoked Responses to Sound after Restricted Ablation of the Auditory Cortex

    Science.gov (United States)

    Lamas, Verónica; Alvarado, Juan C.; Carro, Juan; Merchán, Miguel A.

    2013-01-01

    Introduction This study aimed to assess the top-down control of sound processing in the auditory brainstem of rats. Short latency evoked responses were analyzed after unilateral or bilateral ablation of auditory cortex. This experimental paradigm was also used towards analyzing the long-term evolution of post-lesion plasticity in the auditory system and its ability to self-repair. Method Auditory cortex lesions were performed in rats by stereotactically guided fine-needle aspiration of the cerebrocortical surface. Auditory Brainstem Responses (ABR) were recorded at post-surgery day (PSD) 1, 7, 15 and 30. Recordings were performed under closed-field conditions, using click trains at different sound intensity levels, followed by statistical analysis of threshold values and ABR amplitude and latency variables. Subsequently, brains were sectioned and immunostained for GAD and parvalbumin to assess the location and extent of lesions accurately. Results Alterations in ABR variables depended on the type of lesion and post-surgery time of ABR recordings. Accordingly, bilateral ablations caused a statistically significant increase in thresholds at PSD1 and 7 and a decrease in waves amplitudes at PSD1 that recover at PSD7. No effects on latency were noted at PSD1 and 7, whilst recordings at PSD15 and 30 showed statistically significant decreases in latency. Conversely, unilateral ablations had no effect on auditory thresholds or latencies, while wave amplitudes only decreased at PSD1 strictly in the ipsilateral ear. Conclusion Post-lesion plasticity in the auditory system acts in two time periods: short-term period of decreased sound sensitivity (until PSD7), most likely resulting from axonal degeneration; and a long-term period (up to PSD7), with changes in latency responses and recovery of thresholds and amplitudes values. The cerebral cortex may have a net positive gain on the auditory pathway response to sound. PMID:24066057

  11. Long-term evolution of brainstem electrical evoked responses to sound after restricted ablation of the auditory cortex.

    Directory of Open Access Journals (Sweden)

    Verónica Lamas

    Full Text Available INTRODUCTION: This study aimed to assess the top-down control of sound processing in the auditory brainstem of rats. Short latency evoked responses were analyzed after unilateral or bilateral ablation of auditory cortex. This experimental paradigm was also used towards analyzing the long-term evolution of post-lesion plasticity in the auditory system and its ability to self-repair. METHOD: Auditory cortex lesions were performed in rats by stereotactically guided fine-needle aspiration of the cerebrocortical surface. Auditory Brainstem Responses (ABR were recorded at post-surgery day (PSD 1, 7, 15 and 30. Recordings were performed under closed-field conditions, using click trains at different sound intensity levels, followed by statistical analysis of threshold values and ABR amplitude and latency variables. Subsequently, brains were sectioned and immunostained for GAD and parvalbumin to assess the location and extent of lesions accurately. RESULTS: Alterations in ABR variables depended on the type of lesion and post-surgery time of ABR recordings. Accordingly, bilateral ablations caused a statistically significant increase in thresholds at PSD1 and 7 and a decrease in waves amplitudes at PSD1 that recover at PSD7. No effects on latency were noted at PSD1 and 7, whilst recordings at PSD15 and 30 showed statistically significant decreases in latency. Conversely, unilateral ablations had no effect on auditory thresholds or latencies, while wave amplitudes only decreased at PSD1 strictly in the ipsilateral ear. CONCLUSION: Post-lesion plasticity in the auditory system acts in two time periods: short-term period of decreased sound sensitivity (until PSD7, most likely resulting from axonal degeneration; and a long-term period (up to PSD7, with changes in latency responses and recovery of thresholds and amplitudes values. The cerebral cortex may have a net positive gain on the auditory pathway response to sound.

  12. Tinnitus, Diminished Sound-Level Tolerance, and Elevated Auditory Activity in Humans With Clinically Normal Hearing Sensitivity

    OpenAIRE

    Gu, Jianwen Wendy; Halpin, Christopher F; Nam, Eui-Cheol; Levine, Robert A.; Melcher, Jennifer R.

    2010-01-01

    Phantom sensations and sensory hypersensitivity are disordered perceptions that characterize a variety of intractable conditions involving the somatosensory, visual, and auditory modalities. We report physiological correlates of two perceptual abnormalities in the auditory domain: tinnitus, the phantom perception of sound, and hyperacusis, a decreased tolerance of sound based on loudness. Here, subjects with and without tinnitus, all with clinically normal hearing thresholds, underwent 1) beh...

  13. Evoked response audiometry used in testing auditory organs of miners

    Energy Technology Data Exchange (ETDEWEB)

    Malinowski, T.; Klepacki, J.; Wagstyl, R.

    1980-01-01

    The evoked response audiometry method of testing hearing loss is presented and the results of comparative studies using subjective tonal audiometry and evoked response audiometry in tests of 56 healthy men with good hearing are discussed. The men were divided into three groups according to age and place of work: work place without increased noise; work place with noise and vibrations (at drilling machines); work place with noise and shocks (work at excavators in surface coal mines). The ERA-MKII audiometer produced by the Medelec-Amplaid firm was used. Audiometric threshhold curves for the three groups of tested men are given. At frequencies of 500, 1000 and 4000 Hz mean objective auditory threshhold was shifted by 4-9.5 dB in comparison to the subjective auditory threshold. (21 refs.) (In Polish)

  14. Nocturnal activity positively correlated with auditory sensitivity in noctuoid moths.

    Science.gov (United States)

    ter Hofstede, Hannah M; Ratcliffe, John M; Fullard, James H

    2008-06-23

    We investigated the relationship between predator detection threshold and antipredator behaviour in noctuoid moths. Moths with ears sensitive to the echolocation calls of insectivorous bats use avoidance manoeuvres in flight to evade these predators. Earless moths generally fly less than eared species as a primary defence against predation by bats. For eared moths, however, there is interspecific variation in auditory sensitivity. At the species level, and when controlling for shared evolutionary history, nocturnal flight time and auditory sensitivity were positively correlated in moths, a relationship that most likely reflects selection pressure from aerial-hawking bats. We suggest that species-specific differences in the detection of predator cues are important but often overlooked factors in the evolution and maintenance of antipredator behaviour.

  15. Characterization of the audiologic thresholds in workers of funeral urns

    Directory of Open Access Journals (Sweden)

    Pereira, José Roberto

    2009-09-01

    Full Text Available Introduction: The industrial technological advance has brought benefits and a series of implications that may commit the worker's health and life quality. The exposure to physical, chemical agents and organizational stressors contribute for the increase of work accidents risks. The noise, taken as the most frequent physical agent in the work environment, may cause auditory alterations called Noise-Induced Hearing Loss that affect the communication and life quality of the workers. Objective: To research the auditory health of employees in a funeral urns factory. Method: 90 workers took part in this study, aged between 16 and 52 years, exposed to sound pressure levels equal or higher than 85 dBNPS, vibration and/or chemical agents in the work environment. We carried out a specific interview and Threshold Tonal Audiometry. Results: This study identified altered audiometry results in 13.33% the right ear and 16.67% in the left ear and the age also influenced these auditory thresholds. Conclusion: The accomplishment of a workers' health surveillance program with all people involved is critical and will contribute for the human resources formation, in the management to proceed with actions as well as those by the proper workers being careful of their health.

  16. Temporary threshold shifts from exposures to equal equivalent continuous A-weighted sound pressure level

    DEFF Research Database (Denmark)

    Ordoñez, Rodrigo Pizarro; Hammershøi, Dorte

    2014-01-01

    According to existing methods for the assessment of hearing damage, signals with the same A-weighted equivalent level should pose the same hazard to the auditory system. As a measure of hazard, it is assumed that Temporary Thresholds Shifts (TTS) reflect the onset of alterations to the hearing sy...

  17. Hadron production near threshold

    Indian Academy of Sciences (India)

    Final state interaction effects in → + and → 3He reactions are explored near threshold to study the sensitivity of the cross-sections to the potential and the scattering matrix. The final state scattering wave functions between and and and 3He are described rigorously. The production is ...

  18. Elaborating on Threshold Concepts

    Science.gov (United States)

    Rountree, Janet; Robins, Anthony; Rountree, Nathan

    2013-01-01

    We propose an expanded definition of Threshold Concepts (TCs) that requires the successful acquisition and internalisation not only of knowledge, but also its practical elaboration in the domains of applied strategies and mental models. This richer definition allows us to clarify the relationship between TCs and Fundamental Ideas, and to account…

  19. Non-Monotonic Relation Between Noise Exposure Severity and Neuronal Hyperactivity in the Auditory Midbrain

    Directory of Open Access Journals (Sweden)

    Lara Li Hesse

    2016-08-01

    Full Text Available The occurrence of tinnitus can be linked to hearing loss in the majority of cases, but there is nevertheless a large degree of unexplained heterogeneity in the relation between hearing loss and tinnitus. Part of the problem might be that hearing loss is usually quantified in terms of increased hearing thresholds, which only provides limited information about the underlying cochlear damage. Moreover, noise exposure that does not cause hearing threshold loss can still lead to hidden hearing loss (HHL, i.e. functional deafferentation of auditory nerve fibres (ANFs through loss of synaptic ribbons in inner hair cells. Whilst it is known that increased hearing thresholds can trigger increases in spontaneous neural activity in the central auditory system, i.e. a putative neural correlate of tinnitus, the central effects of HHL have not yet been investigated. Here, we exposed mice to octave-band noise at 100 and 105 dB SPL, to generate HHL and permanent increases of hearing thresholds, respectively. Deafferentation of ANFs was confirmed through measurement of auditory brainstem responses and cochlear immunohistochemistry. Acute extracellular recordings from the auditory midbrain (inferior colliculus demonstrated increases in spontaneous neuronal activity (a putative neural correlate of tinnitus in both groups. Surprisingly the increase in spontaneous activity was most pronounced in the mice with HHL, suggesting that the relation between hearing loss and neuronal hyperactivity might be more complex than currently understood. Our computational model indicated that these differences in neuronal hyperactivity could arise from different degrees of deafferentation of low-threshold ANFs in the two exposure groups.Our results demonstrate that HHL is sufficient to induce changes in central auditory processing, and they also indicate a non-monotonic relationship between cochlear damage and neuronal hyperactivity, suggesting an explanation for why tinnitus might

  20. Influence of Acoustic Overstimulation on the Central Auditory System: An Functional Magnetic Resonance Imaging (fMRI) Study.

    Science.gov (United States)

    Wolak, Tomasz; Cieśla, Katarzyna; Rusiniak, Mateusz; Piłka, Adam; Lewandowska, Monika; Pluta, Agnieszka; Skarżyński, Henryk; Skarżyński, Piotr H

    2016-11-28

    BACKGROUND The goal of the fMRI experiment was to explore the involvement of central auditory structures in pathomechanisms of a behaviorally manifested auditory temporary threshold shift in humans. MATERIAL AND METHODS The material included 18 healthy volunteers with normal hearing. Subjects in the exposure group were presented with 15 min of binaural acoustic overstimulation of narrowband noise (3 kHz central frequency) at 95 dB(A). The control group was not exposed to noise but instead relaxed in silence. Auditory fMRI was performed in 1 session before and 3 sessions after acoustic overstimulation and involved 3.5-4.5 kHz sweeps. RESULTS The outcomes of the study indicate a possible effect of acoustic overstimulation on central processing, with decreased brain responses to auditory stimulation up to 20 min after exposure to noise. The effect can be seen already in the primary auditory cortex. Decreased BOLD signal change can be due to increased excitation thresholds and/or increased spontaneous activity of auditory neurons throughout the auditory system. CONCLUSIONS The trial shows that fMRI can be a valuable tool in acoustic overstimulation studies but has to be used with caution and considered complimentary to audiological measures. Further methodological improvements are needed to distinguish the effects of TTS and neuronal habituation to repetitive stimulation.

  1. Utility of auditory steady-state and brainstem responses in age-related hearing loss in rats.

    Science.gov (United States)

    Sanz-Fernández, Ricardo; Sánchez-Rodriguez, Carolina; Granizo, José Juan; Durio-Calero, Enrique; Martín-Sanz, Eduardo

    2015-01-01

    The results support the idea that auditory steady-state response (ASSR) is a more accurate test for studying age-related hearing loss (ARHL) in Sprague-Dawley rats. Differences in the rat middle ear may explain the variations of the click properties, with a displacement of the energy toward the 8 and 10 kHz frequencies compared with humans. The purpose of this study was to evaluate ARHL in older and younger Sprague-Dawley rats using auditory clicks and tone burst with auditory brainstem response (ABR), in addition to ASSR. This was a prospective cohort study with 50 animals divided into 5 groups based on their age in months. A total of 100 registers were elicited from each one of the 3 auditory measurements systems in an electrically shielded, double-walled, sound-treated cabin. Nine frequencies, from 0.5 to 16 kHz were analyzed with the auditory steady-state response and compared with the results elicited by the clicks and tone-burst ABR. Comparisons between the different frequencies showed lower thresholds in those frequencies below 2 kHz, independently of their age in months. The ARHL was detected by each one of the three auditory measurement systems, but with lower thresholds with the ASSR test. Finally, auditory clicks showed better correlations with 8 and 10 kHz elicited by ASSR, which was different to what was expected, based on human studies.

  2. Influences of multiple memory systems on auditory mental image acuity.

    Science.gov (United States)

    Navarro Cebrian, Ana; Janata, Petr

    2010-05-01

    The influence of different memory systems and associated attentional processes on the acuity of auditory images, formed for the purpose of making intonation judgments, was examined across three experiments using three different task types (cued-attention, imagery, and two-tone discrimination). In experiment 1 the influence of implicit long-term memory for musical scale structure was manipulated by varying the scale degree (leading tone versus tonic) of the probe note about which a judgment had to be made. In experiments 2 and 3 the ability of short-term absolute pitch knowledge to develop was manipulated by presenting blocks of trials in the same key or in seven different keys. The acuity of auditory images depended on all of these manipulations. Within individual listeners, thresholds in the two-tone discrimination and cued-attention conditions were closely related. In many listeners, cued-attention thresholds were similar to thresholds in the imagery condition, and depended on the amount of training individual listeners had in playing a musical instrument. The results indicate that mental images formed at a sensory/cognitive interface for the purpose of making perceptual decisions are highly malleable.

  3. Auditory Brainstem Responses in Children Treated with Cisplatin

    Directory of Open Access Journals (Sweden)

    Mohammad Kamali

    2012-03-01

    Full Text Available Background and Aim: In view of improvement in therapeutic outcome of cancer treatment in children resulting in increased survival rates and the importance of hearing in speech and language development, this research project was intended to assess the effects of cisplatin group on hearing ability in children aged 6 months to 12 years.Methods: In this cross-sectional study, hearing of 10 children on cisplatin group medication for cancer who met the inclusion criteria was examined by recording auditory brainstem responses (ABR using the three stimulants of click and 4 and 8 kHz tone bursts. All children were examined twice: before drug administration and within 72 hours after receiving the last dose. Then the results were compared with each other.Results: There was a significant difference between hearing thresholds before and after drug administration (p<0.05. Right and left ear threshold comparison revealed no significant difference.Conclusion: Ototoxic effects of cisplatin group were confirmed in this study. Insignificant difference observed in comparing right and left ear hearing thresholds could be due to small sample size. auditory brainstem responses test especially with frequency specificity proved to be a useful method in assessing cisplatin ototoxicity.

  4. Multi-sensory integration in brainstem and auditory cortex.

    Science.gov (United States)

    Basura, Gregory J; Koehler, Seth D; Shore, Susan E

    2012-11-16

    Tinnitus is the perception of sound in the absence of a physical sound stimulus. It is thought to arise from aberrant neural activity within central auditory pathways that may be influenced by multiple brain centers, including the somatosensory system. Auditory-somatosensory (bimodal) integration occurs in the dorsal cochlear nucleus (DCN), where electrical activation of somatosensory regions alters pyramidal cell spike timing and rates of sound stimuli. Moreover, in conditions of tinnitus, bimodal integration in DCN is enhanced, producing greater spontaneous and sound-driven neural activity, which are neural correlates of tinnitus. In primary auditory cortex (A1), a similar auditory-somatosensory integration has been described in the normal system (Lakatos et al., 2007), where sub-threshold multisensory modulation may be a direct reflection of subcortical multisensory responses (Tyll et al., 2011). The present work utilized simultaneous recordings from both DCN and A1 to directly compare bimodal integration across these separate brain stations of the intact auditory pathway. Four-shank, 32-channel electrodes were placed in DCN and A1 to simultaneously record tone-evoked unit activity in the presence and absence of spinal trigeminal nucleus (Sp5) electrical activation. Bimodal stimulation led to long-lasting facilitation or suppression of single and multi-unit responses to subsequent sound in both DCN and A1. Immediate (bimodal response) and long-lasting (bimodal plasticity) effects of Sp5-tone stimulation were facilitation or suppression of tone-evoked firing rates in DCN and A1 at all Sp5-tone pairing intervals (10, 20, and 40 ms), and greater suppression at 20 ms pairing-intervals for single unit responses. Understanding the complex relationships between DCN and A1 bimodal processing in the normal animal provides the basis for studying its disruption in hearing loss and tinnitus models. This article is part of a Special Issue entitled: Tinnitus Neuroscience

  5. Suppressed visual looming stimuli are not integrated with auditory looming signals: Evidence from continuous flash suppression.

    Science.gov (United States)

    Moors, Pieter; Huygelier, Hanne; Wagemans, Johan; de-Wit, Lee; van Ee, Raymond

    2015-01-01

    Previous studies using binocular rivalry have shown that signals in a modality other than the visual can bias dominance durations depending on their congruency with the rivaling stimuli. More recently, studies using continuous flash suppression (CFS) have reported that multisensory integration influences how long visual stimuli remain suppressed. In this study, using CFS, we examined whether the contrast thresholds for detecting visual looming stimuli are influenced by a congruent auditory stimulus. In Experiment 1, we show that a looming visual stimulus can result in lower detection thresholds compared to a static concentric grating, but that auditory tone pips congruent with the looming stimulus did not lower suppression thresholds any further. In Experiments 2, 3, and 4, we again observed no advantage for congruent multisensory stimuli. These results add to our understanding of the conditions under which multisensory integration is possible, and suggest that certain forms of multisensory integration are not evident when the visual stimulus is suppressed from awareness using CFS.

  6. Altered auditory and multisensory temporal processing in autism spectrum disorders

    Directory of Open Access Journals (Sweden)

    Leslie D Kwakye

    2011-01-01

    Full Text Available Autism spectrum disorders (ASD are characterized by deficits in social reciprocity and communication, as well as repetitive behaviors and restricted interests. Unusual responses to sensory input and disruptions in the processing of both unisensory and multisensory stimuli have also frequently been reported. However, the specific aspects of sensory processing that are disrupted in ASD have yet to be fully elucidated. Recent published work has shown that children with ASD can integrate low-level audiovisual stimuli, but do so over an extended range of time when compared with typically-developing (TD children. However, the possible contributions of altered unisensory temporal processes to the demonstrated changes in multisensory function are yet unknown. In the current study, unisensory temporal acuity was measured by determining individual thresholds on visual and auditory temporal order judgment (TOJ tasks, and multisensory temporal function was assessed through a cross-modal version of the TOJ task. Whereas no differences in thresholds for the visual TOJ task were seen between children with ASD and TD, thresholds were higher in ASD on the auditory TOJ task, providing preliminary evidence for impairment in auditory temporal processing. On the multisensory TOJ task, children with ASD showed performance improvements over a wider range of temporal intervals than TD children, reinforcing prior work showing an extended temporal window of multisensory integration in ASD. These findings contribute to a better understanding of basic sensory processing differences, which may be critical for understanding more complex social and cognitive deficits in ASD, and ultimately may contribute to more effective diagnostic and interventional strategies.

  7. Altered Auditory and Multisensory Temporal Processing in Autism Spectrum Disorders

    Science.gov (United States)

    Kwakye, Leslie D.; Foss-Feig, Jennifer H.; Cascio, Carissa J.; Stone, Wendy L.; Wallace, Mark T.

    2011-01-01

    Autism spectrum disorders (ASD) are characterized by deficits in social reciprocity and communication, as well as by repetitive behaviors and restricted interests. Unusual responses to sensory input and disruptions in the processing of both unisensory and multisensory stimuli also have been reported frequently. However, the specific aspects of sensory processing that are disrupted in ASD have yet to be fully elucidated. Recent published work has shown that children with ASD can integrate low-level audiovisual stimuli, but do so over an extended range of time when compared with typically developing (TD) children. However, the possible contributions of altered unisensory temporal processes to the demonstrated changes in multisensory function are yet unknown. In the current study, unisensory temporal acuity was measured by determining individual thresholds on visual and auditory temporal order judgment (TOJ) tasks, and multisensory temporal function was assessed through a cross-modal version of the TOJ task. Whereas no differences in thresholds for the visual TOJ task were seen between children with ASD and TD, thresholds were higher in ASD on the auditory TOJ task, providing preliminary evidence for impairment in auditory temporal processing. On the multisensory TOJ task, children with ASD showed performance improvements over a wider range of temporal intervals than TD children, reinforcing prior work showing an extended temporal window of multisensory integration in ASD. These findings contribute to a better understanding of basic sensory processing differences, which may be critical for understanding more complex social and cognitive deficits in ASD, and ultimately may contribute to more effective diagnostic and interventional strategies. PMID:21258617

  8. Auditory and Non-Auditory Contributions for Unaided Speech Recognition in Noise as a Function of Hearing Aid Use.

    Science.gov (United States)

    Gieseler, Anja; Tahden, Maike A S; Thiel, Christiane M; Wagener, Kirsten C; Meis, Markus; Colonius, Hans

    2017-01-01

    Differences in understanding speech in noise among hearing-impaired individuals cannot be explained entirely by hearing thresholds alone, suggesting the contribution of other factors beyond standard auditory ones as derived from the audiogram. This paper reports two analyses addressing individual differences in the explanation of unaided speech-in-noise performance among n = 438 elderly hearing-impaired listeners (mean = 71.1 ± 5.8 years). The main analysis was designed to identify clinically relevant auditory and non-auditory measures for speech-in-noise prediction using auditory (audiogram, categorical loudness scaling) and cognitive tests (verbal-intelligence test, screening test of dementia), as well as questionnaires assessing various self-reported measures (health status, socio-economic status, and subjective hearing problems). Using stepwise linear regression analysis, 62% of the variance in unaided speech-in-noise performance was explained, with measures Pure-tone average (PTA), Age, and Verbal intelligence emerging as the three most important predictors. In the complementary analysis, those individuals with the same hearing loss profile were separated into hearing aid users (HAU) and non-users (NU), and were then compared regarding potential differences in the test measures and in explaining unaided speech-in-noise recognition. The groupwise comparisons revealed significant differences in auditory measures and self-reported subjective hearing problems, while no differences in the cognitive domain were found. Furthermore, groupwise regression analyses revealed that Verbal intelligence had a predictive value in both groups, whereas Age and PTA only emerged significant in the group of hearing aid NU.

  9. Hadron production near threshold

    Indian Academy of Sciences (India)

    Abstract. Final state interaction effects in pp → pΛK+ and pd → 3He η reactions are explored near threshold to study the sensitivity of the cross-sections to the pΛ potential and the ηN scattering matrix. The final state scattering wave functions between Λ and p and η and 3He are described rigorously. The Λ production is ...

  10. [Pathophysiology of auditory and speech perception].

    Science.gov (United States)

    Dauman, René

    2009-05-20

    Auditory perception or hearing can be defined as the interpretation of sensory evidence, produced by the ears in response to sound, in terms of the events that caused the sound. We do not hear a window but we may hear a window closing. We do not hear a dog but we may hear a dog barking. And we do not hear a person but we may hear a person talking. Hearing impairment can result in anxiety or stress in everyday life. Pure-tone hearing loss (or threshold shift) is a measure of hearing impairment. Aging and excessive noise are the main causes of hearing impairment. Speech perception is another concept. The difference with the former is best illustrated by the disabled individual declaring "I can hear that someone is talking to me, but I don't understand what she says". Being unable to understand easily and clearly significant others, especially in understanding speech in a noisy environment, can give rise to considerable psychosocial and professional consequences (disability). Presbycusis is the decline in hearing sensitivity caused by the aging process at different levels of the auditory system. However, it is difficult to isolate age effects from other contributors to age-related hearing loss such as noise damage, genetic susceptibility, inflammatory otologic disorders, and ototoxic agents. Therefore, presbycusis and age-related hearing loss are often used synonymously. In this report pathophysiology is mostly described with regard to presbycusis, and the main peripheral types of presbycusis (sensory or Corti organ-related, strial, and neural) are summarized. An original experimental model of strial presbycusis, based on chronic application of furosemide at the round window, is further described. Central presbycusis is mainly determined by degeneration secondary to peripheral impairment (concept of deafferentation). Central auditory changes typically affect speed of processing and result in poorer speech understanding in noise or with rapid or degraded speech. Last

  11. Air and Bone Conduction Thresholds of Deaf and Normal Hearing Subjects before and during the Elimination of Cutaneous-Tactile Interference with Anesthesia. Final Report.

    Science.gov (United States)

    Nober, E. Harris

    The study investigated whether low frequency air and bone thresholds elicited at high intensity levels from deaf children with a sensory-neural diagnosis reflect valid auditory sensitivity or are mediated through cutaneous-tactile receptors. Subjects were five totally deaf (mean age 17.0) yielding vibrotactile thresholds but with no air and bone…

  12. Devices and Procedures for Auditory Learning.

    Science.gov (United States)

    Ling, Daniel

    1986-01-01

    The article summarizes information on assistive devices (hearing aids, cochlear implants, tactile aids, visual aids) and rehabilitation procedures (auditory training, speechreading, cued speech, and speech production) to aid the auditory learning of the hearing impaired.(DB)

  13. Auditory adaptation improves tactile frequency perception

    NARCIS (Netherlands)

    Crommett, L.E.; Pérez Bellido, A.; Yau, J.M.

    2017-01-01

    Our ability to process temporal frequency information by touch underlies our capacity to perceive and discriminate surface textures. Auditory signals, which also provide extensive temporal frequency information, can systematically alter the perception of vibrations on the hand. How auditory signals

  14. Auditory learning: a developmental method.

    Science.gov (United States)

    Zhang, Yilu; Weng, Juyang; Hwang, Wey-Shiuan

    2005-05-01

    Motivated by the human autonomous development process from infancy to adulthood, we have built a robot that develops its cognitive and behavioral skills through real-time interactions with the environment. We call such a robot a developmental robot. In this paper, we present the theory and the architecture to implement a developmental robot and discuss the related techniques that address an array of challenging technical issues. As an application, experimental results on a real robot, self-organizing, autonomous, incremental learner (SAIL), are presented with emphasis on its audition perception and audition-related action generation. In particular, the SAIL robot conducts the auditory learning from unsegmented and unlabeled speech streams without any prior knowledge about the auditory signals, such as the designated language or the phoneme models. Neither available before learning starts are the actions that the robot is expected to perform. SAIL learns the auditory commands and the desired actions from physical contacts with the environment including the trainers.

  15. Auditory presentation of experimental data

    Science.gov (United States)

    Lunney, David; Morrison, Robert C.

    1990-08-01

    Our research group has been working for several years on the development of auditory alternatives to visual graphs, primarily in order to give blind science students and scientists access to instrumental measurements. In the course of this work we have tried several modes for auditory presentation of data: synthetic speech, tones of varying pitch, complex waveforms, electronic music, and various non-musical sounds. Our most successful translation of data into sound has been presentation of infrared spectra as musical patterns. We have found that if the stick spectra of two compounds are visibly different, their musical patterns will be audibly different. Other possibilities for auditory presentation of data are also described, among them listening to Fourier transforms of spectra, and encoding data in complex waveforms (including synthetic speech).

  16. Context effects on auditory distraction

    Science.gov (United States)

    Chen, Sufen; Sussman, Elyse S.

    2014-01-01

    The purpose of the study was to test the hypothesis that sound context modulates the magnitude of auditory distraction, indexed by behavioral and electrophysiological measures. Participants were asked to identify tone duration, while irrelevant changes occurred in tone frequency, tone intensity, and harmonic structure. Frequency deviants were randomly intermixed with standards (Uni-Condition), with intensity deviants (Bi-Condition), and with both intensity and complex deviants (Tri-Condition). Only in the Tri-Condition did the auditory distraction effect reflect the magnitude difference among the frequency and intensity deviants. The mixture of the different types of deviants in the Tri-Condition modulated the perceived level of distraction, demonstrating that the sound context can modulate the effect of deviance level on processing irrelevant acoustic changes in the environment. These findings thus indicate that perceptual contrast plays a role in change detection processes that leads to auditory distraction. PMID:23886958

  17. Auditory Hallucinations in Acute Stroke

    Directory of Open Access Journals (Sweden)

    Yair Lampl

    2005-01-01

    Full Text Available Auditory hallucinations are uncommon phenomena which can be directly caused by acute stroke, mostly described after lesions of the brain stem, very rarely reported after cortical strokes. The purpose of this study is to determine the frequency of this phenomenon. In a cross sectional study, 641 stroke patients were followed in the period between 1996–2000. Each patient underwent comprehensive investigation and follow-up. Four patients were found to have post cortical stroke auditory hallucinations. All of them occurred after an ischemic lesion of the right temporal lobe. After no more than four months, all patients were symptom-free and without therapy. The fact the auditory hallucinations may be of cortical origin must be taken into consideration in the treatment of stroke patients. The phenomenon may be completely reversible after a couple of months.

  18. Octave effect in auditory attention.

    Science.gov (United States)

    Borra, Tobias; Versnel, Huib; Kemner, Chantal; van Opstal, A John; van Ee, Raymond

    2013-09-17

    After hearing a tone, the human auditory system becomes more sensitive to similar tones than to other tones. Current auditory models explain this phenomenon by a simple bandpass attention filter. Here, we demonstrate that auditory attention involves multiple pass-bands around octave-related frequencies above and below the cued tone. Intriguingly, this "octave effect" not only occurs for physically presented tones, but even persists for the missing fundamental in complex tones, and for imagined tones. Our results suggest neural interactions combining octave-related frequencies, likely located in nonprimary cortical regions. We speculate that this connectivity scheme evolved from exposure to natural vibrations containing octave-related spectral peaks, e.g., as produced by vocal cords.

  19. Threshold Concepts in Research Education and Evidence of Threshold Crossing

    Science.gov (United States)

    Kiley, Margaret; Wisker, Gina

    2009-01-01

    Most work on threshold concepts has hitherto related to discipline-specific undergraduate education, however, the idea of generic doctoral-level threshold concepts appeared to us to provide a strong and useful framework to support research learning and teaching at the graduate level. The early work regarding research-level threshold concepts is…

  20. A loudspeaker-based room auralization system for auditory perception research

    DEFF Research Database (Denmark)

    Buchholz, Jörg; Favrot, Sylvain Emmanuel

    2009-01-01

    . This system provides a flexible research platform for conducting auditory experiments with normal-hearing, hearing-impaired, and aided hearing-impaired listeners in a fully controlled and realistic environment. This includes measures of basic auditory function (e.g., signal detection, distance perception......) and measures of speech intelligibility. A battery of objective tests (e.g., reverberation time, clarity, interaural correlation coefficient) and subjective tests (e.g., speech reception thresholds) is presented that demonstrates the applicability of the LoRA system....

  1. The auditory cortex of the bat Phyllostomus discolor: Localization and organization of basic response properties

    Directory of Open Access Journals (Sweden)

    Schwellnus Britta

    2008-07-01

    Full Text Available Abstract Background The mammalian auditory cortex can be subdivided into various fields characterized by neurophysiological and neuroarchitectural properties and by connections with different nuclei of the thalamus. Besides the primary auditory cortex, echolocating bats have cortical fields for the processing of temporal and spectral features of the echolocation pulses. This paper reports on location, neuroarchitecture and basic functional organization of the auditory cortex of the microchiropteran bat Phyllostomus discolor (family: Phyllostomidae. Results The auditory cortical area of P. discolor is located at parieto-temporal portions of the neocortex. It covers a rostro-caudal range of about 4800 μm and a medio-lateral distance of about 7000 μm on the flattened cortical surface. The auditory cortices of ten adult P. discolor were electrophysiologically mapped in detail. Responses of 849 units (single neurons and neuronal clusters up to three neurons to pure tone stimulation were recorded extracellularly. Cortical units were characterized and classified depending on their response properties such as best frequency, auditory threshold, first spike latency, response duration, width and shape of the frequency response area and binaural interactions. Based on neurophysiological and neuroanatomical criteria, the auditory cortex of P. discolor could be subdivided into anterior and posterior ventral fields and anterior and posterior dorsal fields. The representation of response properties within the different auditory cortical fields was analyzed in detail. The two ventral fields were distinguished by their tonotopic organization with opposing frequency gradients. The dorsal cortical fields were not tonotopically organized but contained neurons that were responsive to high frequencies only. Conclusion The auditory cortex of P. discolor resembles the auditory cortex of other phyllostomid bats in size and basic functional organization. The

  2. Effect of passive smoking on auditory temporal resolution in children.

    Science.gov (United States)

    Durante, Alessandra Spada; Massa, Beatriz; Pucci, Beatriz; Gudayol, Nicolly; Gameiro, Marcella; Lopes, Cristiane

    2017-06-01

    To determine the effect of passive smoking on auditory temporal resolution in primary school children, based on the hypothesis that individuals who are exposed to smoking exhibit impaired performance. Auditory temporal resolution was evaluated using the Gaps In Noise (GIN) test. Exposure to passive smoking was assessed by measuring nicotine metabolite (cotinine) excreted in the first urine of the day. The study included 90 children with mean age of 10.2 ± 0.1 years old from a public school in São Paulo. Participants were divided into two groups: a study group, comprising 45 children exposed to passive smoking (cotinine > 5 ng/mL); and a control group, constituting 45 children who were not exposed to passive smoking. All participants had normal audiometry and immittance test results. Statistically significant differences (p passive smoking had poorer performance both in terms of thresholds and correct responses percentage on auditory temporal resolution assessment. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Amelioration of Auditory Response by DA9801 in Diabetic Mouse

    Directory of Open Access Journals (Sweden)

    Yeong Ro Lee

    2015-01-01

    Full Text Available Diabetes mellitus (DM is a metabolic disease that involves disorders such as diabetic retinopathy, diabetic neuropathy, and diabetic hearing loss. Recently, neurotrophin has become a treatment target that has shown to be an attractive alternative in recovering auditory function altered by DM. The aim of this study was to evaluate the effect of DA9801, a mixture of Dioscorea nipponica and Dioscorea japonica extracts, in the auditory function damage produced in a STZ-induced diabetic model and to provide evidence of the mechanisms involved in enhancing these protective effects. We found a potential application of DA9801 on hearing impairment in the STZ-induced diabetic model, demonstrated by reducing the deterioration produced by DM in ABR threshold in response to clicks and normalizing wave I–IV latencies and Pa latencies in AMLR. We also show evidence that these effects might be elicited by inducing NGF related through Nr3c1 and Akt. Therefore, this result suggests that the neuroprotective effects of DA9801 on the auditory damage produced by DM may be affected by NGF increase resulting from Nr3c1 via Akt transformation.

  4. Utilização de uma manobra específica para evitar alterações dos limiares auditivos causadas pelo colabamento do meato acústico externo The use of a specific maneuver to avoid alterations of the auditory thresholds caused by the collapse of the external acoustic meatus

    Directory of Open Access Journals (Sweden)

    Luciana Karla Moreira Amaral

    2008-01-01

    Full Text Available OBJETIVO: verificar se a utilização de uma manobra de reposicionamento dos fones em caso de suspeita de colabamento pode alterar os limiares auditivos nas freqüências altas, melhorando-os. MÉTODOS: participaram do estudo 89 indivíduos com idades entre 18 e 35 anos, e que apresentavam diferença maior ou igual a 10 dB NA nos limiares das freqüências de 6000 e 8000 Hz em relação à freqüência de 4000 Hz. Foi realizado o re-teste dos limiares auditivos nas freqüências de 4000, 6000 e 8000 Hz, a partir do reposicionamento dos fones e utilização de manobra específica, que consistiu em orientar o paciente, pedindo ao mesmo que segurasse o fone bem próximo à orelha, sem pressionála, evitando, desta forma, o colabamento do meato acústico externo. RESULTADOS: de acordo com os dados obtidos por meio deste estudo, pôde ser verificada melhora significativa dos limiares auditivos com a utilização da manobra descrita neste estudo em 60,7% dos indivíduos avaliados. CONCLUSÃO: a partir dos resultados, foi possível verificar que o colabamento do meato acústico externo, causado pela pressão dos fones pode interferir nos resultados das audiometrias tonais, bem como foi possível observar a eficácia da manobra descrita neste estudo para minimizar interferência deste fenômeno.PURPOSE: to check the use of a maneuver of reposition of the earphones in case of collapse suspicion can alter the hearing thresholds for high frequencies, improving the same ones. METHODS: 89 individuals participated in the study, with age between 18 and 35 years, wich presented larger difference or same to 10 dBNA in the thresholds of the frequencies of 6000 and 8000 Hz in relation to frequency of 4000Hz. Retest of the hearing thresholds was accomplished in the frequencies of 4000, 6000 and 8000 Hz, starting from the reposition of the earphones and use of specific maneuver, that consisted of guiding the patient, asking him to held the earphone very close to the

  5. Early auditory enrichment with music enhances auditory discrimination learning and alters NR2B protein expression in rat auditory cortex.

    Science.gov (United States)

    Xu, Jinghong; Yu, Liping; Cai, Rui; Zhang, Jiping; Sun, Xinde

    2009-01-03

    Previous studies have shown that the functional development of auditory system is substantially influenced by the structure of environmental acoustic inputs in early life. In our present study, we investigated the effects of early auditory enrichment with music on rat auditory discrimination learning. We found that early auditory enrichment with music from postnatal day (PND) 14 enhanced learning ability in auditory signal-detection task and in sound duration-discrimination task. In parallel, a significant increase was noted in NMDA receptor subunit NR2B protein expression in the auditory cortex. Furthermore, we found that auditory enrichment with music starting from PND 28 or 56 did not influence NR2B expression in the auditory cortex. No difference was found in the NR2B expression in the inferior colliculus (IC) between music-exposed and normal rats, regardless of when the auditory enrichment with music was initiated. Our findings suggest that early auditory enrichment with music influences NMDA-mediated neural plasticity, which results in enhanced auditory discrimination learning.

  6. Renewal-process approximation of a stochastic threshold model for electrical neural stimulation.

    Science.gov (United States)

    Bruce, I C; Irlicht, L S; White, M W; O'Leary, S J; Clark, G M

    2000-01-01

    In a recent set of modeling studies we have developed a stochastic threshold model of auditory nerve response to single biphasic electrical pulses (Bruce et al., 1999c) and moderate rate (less than 800 pulses per second) pulse trains (Bruce et al., 1999a). In this article we derive an analytical approximation for the single-pulse model, which is then extended to describe the pulse-train model in the case of evenly timed, uniform pulses. This renewal-process description provides an accurate and computationally efficient model of electrical stimulation of single auditory nerve fibers by a cochlear implant that may be extended to other forms of electrical neural stimulation.

  7. Short-wavelength infrared laser activates the auditory neurons: comparing the effect of 980 vs. 810 nm wavelength.

    Science.gov (United States)

    Tian, Lan; Wang, Jingxuan; Wei, Ying; Lu, Jianren; Xu, Anting; Xia, Ming

    2017-02-01

    Research on auditory neural triggering by optical stimulus has been developed as an emerging technique to elicit the auditory neural response, which may provide an alternative method to the cochlear implants. However, most previous studies have been focused on using longer-wavelength near-infrared (>1800 nm) laser. The effect comparison of different laser wavelengths in short-wavelength infrared (SWIR) range on the auditory neural stimulation has not been previously explored. In this study, the pulsed 980- and 810-nm SWIR lasers were applied as optical stimuli to irradiate the auditory neurons in the cochlea of five deafened guinea pigs and the neural response under the two laser wavelengths was compared by recording the evoked optical auditory brainstem responses (OABRs). In addition, the effect of radiant exposure, laser pulse width, and threshold with the two laser wavelengths was further investigated and compared. The one-way analysis of variance (ANOVA) was used to analyze those data. Results showed that the OABR amplitude with the 980-nm laser is higher than the amplitude with the 810-nm laser under the same radiant exposure from 10 to 102 mJ/cm(2). And the laser stimulation of 980 nm wavelength has lower threshold radiant exposure than the 810 nm wavelength at varied pulse duration in 20-500 μs range. Moreover, the 810-nm laser has a wider optimized pulse duration range than the 980-nm laser for the auditory neural stimulation.

  8. Uniform degradation of auditory acuity in subjects with normal hearing leads to unequal precedence effects.

    Science.gov (United States)

    Champoux, François; Houde, Marie-Soleil; Gagné, Jean-Pierre; Kelly, Jack B

    2009-06-01

    The aim of this study was to investigate whether a controlled unilateral reduction in auditory acuity at the higher audiometric frequencies would have an effect on the variability in responses obtained on a task designed to measure the precedence effect. The experiment was conducted with participants located in a large sound proof, anechoic room, and psychophysical tests were conducted with long-duration noise burst stimuli. Reduction in auditory acuity was created by inserting a specially designed earplug in the ear of participants with normal hearing. The earplugs produced a highly reliable increase in the thresholds for detecting high-frequency sounds in the blocked ear with the largest effect at the highest frequencies (4 and 8 kHz). Across-participant variability in tone-detection threshold was less than +/-5 dB. The measurement of lag-burst thresholds with and without the insertion of earplugs was used to characterize the precedence effect. The lag-burst threshold was defined as the shortest lag-burst delay that yielded a perception of two different noise bursts. Although performance was stable across participants in the condition without the earplug, a substantial increase in variability in the lag-burst thresholds was found in the earplug condition. These results indicate that a uniform unilateral degradation in auditory acuity leads to increased variability in performance on tasks measuring fusion in the precedence effect. The outcome suggests that variable perception of the precedence effect by individuals with clinically diagnosed hearing loss might be due to factors other than a reduction in auditory acuity per se.

  9. The auditory system of non-calling grasshoppers (Melanoplinae: Podismini) and the evolutionary regression of their tympanal ears.

    Science.gov (United States)

    Lehmann, Gerlind U C; Berger, Sandra; Strauss, Johannes; Lehmann, Arne W; Pflüger, Hans-Joachim

    2010-11-01

    Reduction of tympanal hearing organs is repeatedly found amongst insects and is associated with weakened selection for hearing. There is also an associated wing reduction, since flight is no longer required to evade bats. Wing reduction may also affect sound production. Here, the auditory system in four silent grasshopper species belonging to the Podismini is investigated. In this group, tympanal ears occur but sound signalling does not. The tympanal organs range from fully developed to remarkably reduced tympana. To evaluate the effects of tympanal regression on neuronal organisation and auditory sensitivity, the size of wings and tympana, sensory thresholds and sensory central projections are compared. Reduced tympanal size correlates with a higher auditory threshold. The threshold curves of all four species are tuned to low frequencies with a maximal sensitivity at 3-5 kHz. Central projections of the tympanal nerve show characteristics known from fully tympanate acridid species, so neural elements for tympanal hearing have been strongly conserved across these species. The results also confirm the correlation between reduction in auditory sensitivity and wing reduction. It is concluded that the auditory sensitivity of all four species may be maintained by stabilising selective forces, such as predation.

  10. Auditory Hallucinations Nomenclature and Classification

    NARCIS (Netherlands)

    Blom, Jan Dirk; Sommer, Iris E. C.

    Introduction: The literature on the possible neurobiologic correlates of auditory hallucinations is expanding rapidly. For an adequate understanding and linking of this emerging knowledge, a clear and uniform nomenclature is a prerequisite. The primary purpose of the present article is to provide an

  11. Auditory Risk of Air Rifles

    Science.gov (United States)

    Lankford, James E.; Meinke, Deanna K.; Flamme, Gregory A.; Finan, Donald S.; Stewart, Michael; Tasko, Stephen; Murphy, William J.

    2016-01-01

    Objective To characterize the impulse noise exposure and auditory risk for air rifle users for both youth and adults. Design Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit and LAeq75 exposure limit suggested by the World Health Organization (1999) for children. Study sample Impulses were generated by 9 pellet air rifles and 1 BB air rifle. Results None of the air rifles generated peak levels that exceeded the 140 dB peak limit for adults and 8 (80%) exceeded the 120 dB peak SPL limit for youth. In general, for both adults and youth there is minimal auditory risk when shooting less than 100 unprotected shots with pellet air rifles. Air rifles with suppressors were less hazardous than those without suppressors and the pellet air rifles with higher velocities were generally more hazardous than those with lower velocities. Conclusion To minimize auditory risk, youth should utilize air rifles with an integrated suppressor and lower velocity ratings. Air rifle shooters are advised to wear hearing protection whenever engaging in shooting activities in order to gain self-efficacy and model appropriate hearing health behaviors necessary for recreational firearm use. PMID:26840923

  12. Molecular approach of auditory neuropathy.

    Science.gov (United States)

    Silva, Magali Aparecida Orate Menezes da; Piatto, Vânia Belintani; Maniglia, Jose Victor

    2015-01-01

    Mutations in the otoferlin gene are responsible for auditory neuropathy. To investigate the prevalence of mutations in the mutations in the otoferlin gene in patients with and without auditory neuropathy. This original cross-sectional case study evaluated 16 index cases with auditory neuropathy, 13 patients with sensorineural hearing loss, and 20 normal-hearing subjects. DNA was extracted from peripheral blood leukocytes, and the mutations in the otoferlin gene sites were amplified by polymerase chain reaction/restriction fragment length polymorphism. The 16 index cases included nine (56%) females and seven (44%) males. The 13 deaf patients comprised seven (54%) males and six (46%) females. Among the 20 normal-hearing subjects, 13 (65%) were males and seven were (35%) females. Thirteen (81%) index cases had wild-type genotype (AA) and three (19%) had the heterozygous AG genotype for IVS8-2A-G (intron 8) mutation. The 5473C-G (exon 44) mutation was found in a heterozygous state (CG) in seven (44%) index cases and nine (56%) had the wild-type allele (CC). Of these mutants, two (25%) were compound heterozygotes for the mutations found in intron 8 and exon 44. All patients with sensorineural hearing loss and normal-hearing individuals did not have mutations (100%). There are differences at the molecular level in patients with and without auditory neuropathy. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  13. Nigel: A Severe Auditory Dyslexic

    Science.gov (United States)

    Cotterell, Gill

    1976-01-01

    Reported is the case study of a boy with severe auditory dyslexia who received remedial treatment from the age of four and progressed through courses at a technical college and a 3-year apprenticeship course in mechanics by the age of eighteen. (IM)

  14. Auditory Processing Disorder in Children

    Science.gov (United States)

    ... Auditory Neuropathy Autism Spectrum Disorder: Communication Problems in Children Dysphagia Quick Statistics About Voice, Speech, Language Speech and Language Developmental Milestones What Is Voice? What Is Speech? What Is Language? ... communication provides better outcomes for children with cochlear implants University of Texas at Dallas ...

  15. Network Analysis of Functional Brain Connectivity Driven by Gamma-Band Auditory Steady-State Response in Auditory Hallucinations.

    Science.gov (United States)

    Ying, Jun; Zhou, Dan; Lin, Ke; Gao, Xiaorong

    The auditory steady-state response (ASSR) may reflect activity from different regions of the brain. Particularly, it was reported that the gamma-band ASSR plays an important role in working memory, speech understanding, and recognition. Traditionally, the ASSR has been determined by power spectral density analysis, which cannot detect the exact overall distributed properties of the ASSR. Functional network analysis has recently been applied in electroencephalography studies. Previous studies on resting or working state found a small-world organization of the brain network. Some researchers have studied dysfunctional networks caused by diseases. The present study investigates the brain connection networks of schizophrenia patients with auditory hallucinations during an ASSR task. A directed transfer function is utilized to estimate the brain connectivity patterns. Moreover, the structures of brain networks are analyzed by converting the connectivity matrices into graphs. It is found that for normal subjects, network connections are mainly distributed at the central and frontal-temporal regions. This indicates that the central regions act as transmission hubs of information under ASSR stimulation. For patients, network connections seem unordered. The finding that the path length was larger in patients compared to that in normal subjects under most thresholds provides insight into the structures of connectivity patterns. The results suggest that there are more synchronous oscillations that cover a long distance on the cortex but a less efficient network for patients with auditory hallucinations.

  16. New perspectives on the auditory cortex: learning and memory.

    Science.gov (United States)

    Weinberger, Norman M

    2015-01-01

    Primary ("early") sensory cortices have been viewed as stimulus analyzers devoid of function in learning, memory, and cognition. However, studies combining sensory neurophysiology and learning protocols have revealed that associative learning systematically modifies the encoding of stimulus dimensions in the primary auditory cortex (A1) to accentuate behaviorally important sounds. This "representational plasticity" (RP) is manifest at different levels. The sensitivity and selectivity of signal tones increase near threshold, tuning above threshold shifts toward the frequency of acoustic signals, and their area of representation can increase within the tonotopic map of A1. The magnitude of area gain encodes the level of behavioral stimulus importance and serves as a substrate of memory strength. RP has the same characteristics as behavioral memory: it is associative, specific, develops rapidly, consolidates, and can last indefinitely. Pairing tone with stimulation of the cholinergic nucleus basalis induces RP and implants specific behavioral memory, while directly increasing the representational area of a tone in A1 produces matching behavioral memory. Thus, RP satisfies key criteria for serving as a substrate of auditory memory. The findings suggest a basis for posttraumatic stress disorder in abnormally augmented cortical representations and emphasize the need for a new model of the cerebral cortex. © 2015 Elsevier B.V. All rights reserved.

  17. Did auditory sensitivity and vocalization evolve independently in otophysan fishes?

    Science.gov (United States)

    Ladich, F

    1999-01-01

    Otophysine fishes have a series of bones, the Weberian ossicles, which acoustically couple the swimbladder to the inner ear. These fishes have evolved a diversity of sound-generating organs and acoustic signals, although some species, such as the goldfish, are not known to be vocal. Utilizing a recently developed auditory brainstem response (ABR)-recording technique, the auditory sensitivities of representatives of seven families from all four otophysine orders were investigated and compared to the spectral content of their vocalizations. All species examined detect tone bursts from 100 Hz to 5 kHz, but ABR-audiograms revealed major differences in auditory sensitivities, especially at higher frequencies (>1 kHz) where thresholds differed by up to 50 dB. These differences showed no apparent correspondence to the ability to produce sounds (vocal versus non-vocal species) or to the spectral content of species-specific sounds. All fishes have maximum sensitivity between 400 Hz and 1,500 Hz, whereas the major portion of the energy of acoustic signals was in the frequency range of 100-400 Hz (swimbladder drumming sounds) and of 1-3 kHz (stridulatory sounds). Species producing stridulatory sounds exhibited better high-frequency hearing sensitivity (pimelodids, doradids), except for callichthyids, which had poorest hearing ability in this range. Furthermore, fishes emitting both low- and high-frequency sounds, such as pimelodid and doradid catfishes, did not possess two corresponding auditory sensitivity maxima. Based on these results it is concluded that selective pressures involved in the evolution of the Weberian apparatus and the design of vocal signals in otophysines were others (primarily predator or prey detection in quiet freshwater habitats) than those serving to optimize acoustical communication.

  18. Functional Changes in the Human Auditory Cortex in Ageing

    Science.gov (United States)

    Profant, Oliver; Tintěra, Jaroslav; Balogová, Zuzana; Ibrahim, Ibrahim; Jilek, Milan; Syka, Josef

    2015-01-01

    Hearing loss, presbycusis, is one of the most common sensory declines in the ageing population. Presbycusis is characterised by a deterioration in the processing of temporal sound features as well as a decline in speech perception, thus indicating a possible central component. With the aim to explore the central component of presbycusis, we studied the function of the auditory cortex by functional MRI in two groups of elderly subjects (>65 years) and compared the results with young subjects (presbycusis (EP) differed from the elderly group with mild presbycusis (MP) in hearing thresholds measured by pure tone audiometry, presence and amplitudes of transient otoacoustic emissions (TEOAE) and distortion-product oto-acoustic emissions (DPOAE), as well as in speech-understanding under noisy conditions. Acoustically evoked activity (pink noise centered around 350 Hz, 700 Hz, 1.5 kHz, 3 kHz, 8 kHz), recorded by BOLD fMRI from an area centered on Heschl’s gyrus, was used to determine age-related changes at the level of the auditory cortex. The fMRI showed only minimal activation in response to the 8 kHz stimulation, despite the fact that all subjects heard the stimulus. Both elderly groups showed greater activation in response to acoustical stimuli in the temporal lobes in comparison with young subjects. In addition, activation in the right temporal lobe was more expressed than in the left temporal lobe in both elderly groups, whereas in the young control subjects (YC) leftward lateralization was present. No statistically significant differences in activation of the auditory cortex were found between the MP and EP groups. The greater extent of cortical activation in elderly subjects in comparison with young subjects, with an asymmetry towards the right side, may serve as a compensatory mechanism for the impaired processing of auditory information appearing as a consequence of ageing. PMID:25734519

  19. Functional changes in the human auditory cortex in ageing.

    Directory of Open Access Journals (Sweden)

    Oliver Profant

    Full Text Available Hearing loss, presbycusis, is one of the most common sensory declines in the ageing population. Presbycusis is characterised by a deterioration in the processing of temporal sound features as well as a decline in speech perception, thus indicating a possible central component. With the aim to explore the central component of presbycusis, we studied the function of the auditory cortex by functional MRI in two groups of elderly subjects (>65 years and compared the results with young subjects (thresholds measured by pure tone audiometry, presence and amplitudes of transient otoacoustic emissions (TEOAE and distortion-product oto-acoustic emissions (DPOAE, as well as in speech-understanding under noisy conditions. Acoustically evoked activity (pink noise centered around 350 Hz, 700 Hz, 1.5 kHz, 3 kHz, 8 kHz, recorded by BOLD fMRI from an area centered on Heschl's gyrus, was used to determine age-related changes at the level of the auditory cortex. The fMRI showed only minimal activation in response to the 8 kHz stimulation, despite the fact that all subjects heard the stimulus. Both elderly groups showed greater activation in response to acoustical stimuli in the temporal lobes in comparison with young subjects. In addition, activation in the right temporal lobe was more expressed than in the left temporal lobe in both elderly groups, whereas in the young control subjects (YC leftward lateralization was present. No statistically significant differences in activation of the auditory cortex were found between the MP and EP groups. The greater extent of cortical activation in elderly subjects in comparison with young subjects, with an asymmetry towards the right side, may serve as a compensatory mechanism for the impaired processing of auditory information appearing as a consequence of ageing.

  20. The encoding of auditory objects in auditory cortex: insights from magnetoencephalography.

    Science.gov (United States)

    Simon, Jonathan Z

    2015-02-01

    Auditory objects, like their visual counterparts, are perceptually defined constructs, but nevertheless must arise from underlying neural circuitry. Using magnetoencephalography (MEG) recordings of the neural responses of human subjects listening to complex auditory scenes, we review studies that demonstrate that auditory objects are indeed neurally represented in auditory cortex. The studies use neural responses obtained from different experiments in which subjects selectively listen to one of two competing auditory streams embedded in a variety of auditory scenes. The auditory streams overlap spatially and often spectrally. In particular, the studies demonstrate that selective attentional gain does not act globally on the entire auditory scene, but rather acts differentially on the separate auditory streams. This stream-based attentional gain is then used as a tool to individually analyze the different neural representations of the competing auditory streams. The neural representation of the attended stream, located in posterior auditory cortex, dominates the neural responses. Critically, when the intensities of the attended and background streams are separately varied over a wide intensity range, the neural representation of the attended speech adapts only to the intensity of that speaker, irrespective of the intensity of the background speaker. This demonstrates object-level intensity gain control in addition to the above object-level selective attentional gain. Overall, these results indicate that concurrently streaming auditory objects, even if spectrally overlapping and not resolvable at the auditory periphery, are individually neurally encoded in auditory cortex, as separate objects. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Follow-up of hearing thresholds among forge hammering workers

    Energy Technology Data Exchange (ETDEWEB)

    Kamal, A.A.; Mikael, R.A.; Faris, R. (Ain Shams Univ., Abbasia, Cairo (Egypt))

    1989-01-01

    Hearing threshold was reexamined in a group of forge hammering workers investigated 8 years ago with consideration of the age effect and of auditory symptoms. Workers were exposed to impact noise that ranged from 112 to 139 dB(A)--at an irregular rate of 20 to 50 drop/minute--and a continuous background noise that ranged from 90 to 94 dB(A). Similar to what was observed 8 years ago, the present permanent threshold shift (PTS) showed a maximum notch at the frequency of 6 kHz and considerable elevations at the frequencies of 0.25-1 kHz. The age-corrected PTS and the postexposure hearing threshold were significantly higher than the corresponding previous values at the frequencies 0.25, 0.5, 1, and 8 kHz only. The rise was more evident at the low than at the high frequencies. Temporary threshold shift (TTS) values were significantly less than those 8 years ago. Contrary to the previous TTS, the present TTS were higher at low than at high frequencies. Although progression of PTS at the frequencies 0.25 and 0.5 kHz was continuous throughout the observed durations of exposure, progression at higher frequencies occurred essentially in the first 10 to 15 years of exposure. Thereafter, it followed a much slower rate. Tinnitus was significantly associated with difficulty in hearing the human voice and with elevation of PTS at all the tested frequencies, while acoustic after-image was significantly associated with increment of PTS at the frequencies 0.25-2 kHz. No relation between PTS and smoking was found. PTS at low frequencies may provide an indication of progression of hearing damage when the sensitivity at 6 and 4 kHz diminishes after prolonged years of exposure. Tinnitus and acoustic after-image are related to the auditory effect of forge hammering noise.

  2. Comparison of auditory deficits associated with neglect and auditory cortex lesions.

    Science.gov (United States)

    Gutschalk, Alexander; Brandt, Tobias; Bartsch, Andreas; Jansen, Claudia

    2012-04-01

    In contrast to lesions of the visual and somatosensory cortex, lesions of the auditory cortex are not associated with self-evident contralesional deficits. Only when two or more stimuli are presented simultaneously to the left and right, contralesional extinction has been observed after unilateral lesions of the auditory cortex. Because auditory extinction is also considered a sign of neglect, clinical separation of auditory neglect from deficits caused by lesions of the auditory cortex is challenging. Here, we directly compared a number of tests previously used for either auditory-cortex lesions or neglect in 29 controls and 27 patients suffering from unilateral auditory-cortex lesions, neglect, or both. The results showed that a dichotic-speech test revealed similar amounts of extinction for both auditory cortex lesions and neglect. Similar results were obtained for words lateralized by inter-aural time differences. Consistent extinction after auditory cortex lesions was also observed in a dichotic detection task. Neglect patients showed more general problems with target detection but no consistent extinction in the dichotic detection task. In contrast, auditory lateralization perception was biased toward the right in neglect but showed considerably less disruption by auditory cortex lesions. Lateralization of auditory-evoked magnetic fields in auditory cortex was highly correlated with extinction in the dichotic target-detection task. Moreover, activity in the right primary auditory cortex was somewhat reduced in neglect patients. The results confirm that auditory extinction is observed with lesions of the auditory cortex and auditory neglect. A distinction can nevertheless be made with dichotic target-detection tasks, auditory-lateralization perception, and magnetoencephalography. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Intraoperative auditory steady state response measurements during Vibrant Soundbridge middle ear implantation in patients with mixed hearing loss: preliminary results.

    NARCIS (Netherlands)

    Verhaegen, V.J.O.; Mulder, J.J.S.; Noten, J.F.P.; Luijten, B.M.A.; Cremers, C.W.R.J.; Snik, A.F.M.

    2010-01-01

    OBJECTIVE: To optimize intraoperatively the coupling of the floating mass transducer (FMT) of the Vibrant Soundbridge middle ear implant to the round or oval cochlear window in patients with mixed hearing loss. STUDY DESIGN: Intraoperative measurement of objective hearing thresholds using auditory

  4. Auditory event files: integrating auditory perception and action planning.

    Science.gov (United States)

    Zmigrod, Sharon; Hommel, Bernhard

    2009-02-01

    The features of perceived objects are processed in distinct neural pathways, which call for mechanisms that integrate the distributed information into coherent representations (the binding problem). Recent studies of sequential effects have demonstrated feature binding not only in perception, but also across (visual) perception and action planning. We investigated whether comparable effects can be obtained in and across auditory perception and action. The results from two experiments revealed effects indicative of spontaneous integration of auditory features (pitch and loudness, pitch and location), as well as evidence for audio-manual stimulus-response integration. Even though integration takes place spontaneously, features related to task-relevant stimulus or response dimensions are more likely to be integrated. Moreover, integration seems to follow a temporal overlap principle, with features coded close in time being more likely to be bound together. Taken altogether, the findings are consistent with the idea of episodic event files integrating perception and action plans.

  5. Auditory brainstem and cortical potentials following bone-anchored hearing aid stimulation.

    Science.gov (United States)

    Rahne, Torsten; Ehelebe, Thomas; Rasinski, Christine; Götze, Gerrit

    2010-11-30

    Patients suffering from conductive or mixed hearing loss and Single-Sided Deafness may benefit from implantable hearing devices relying on bone conducted auditory stimulation. However, with only passively cooperative patients, objective methods are needed to estimate the aided and unaided pure-tone audiogram. This study focuses on the feasibility aspect of an electrophysiological determination of the hearing thresholds with bone-anchored hearing aid stimulation. Therefore, 10 normal-hearing subjects were provided with a Baha Intenso (Cochlear Ltd.) which was temporarily connected to the Baha Softband (Cochlear Ltd.). Auditory evoked potentials were measured by auditory stimulation paradigm used in clinical routine. The amplitudes, latencies, and thresholds of the resulting auditory brainstem responses (ABR) and the cortically evoked responses (CAEP) were correlated with the respective responses without the use of the Baha Intenso. The recording of ABR and CAEP by delivering the stimuli to the Baha results in response waveforms which are comparable to those evoked by earphone stimulation and appears appropriate to be measured using the Baha Intenso as stimulator. At the ABR recordings a stimulus artifact at higher stimulation levels and a constant latency shift caused by the Baha Intenso has to be considered. The CAEP recording appeared promising as a frequency specific objective method to approve the fitting of bone-anchored hearing aids. At all measurements, the ABR and CAEP thresholds seem to be consistent with the normal hearing of the investigated participants. Thus, a recording of auditory evoked potentials using a Baha is in general possible if specific limitations are considered. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. The auditory brainstem is a barometer of rapid auditory learning.

    Science.gov (United States)

    Skoe, E; Krizman, J; Spitzer, E; Kraus, N

    2013-07-23

    To capture patterns in the environment, neurons in the auditory brainstem rapidly alter their firing based on the statistical properties of the soundscape. How this neural sensitivity relates to behavior is unclear. We tackled this question by combining neural and behavioral measures of statistical learning, a general-purpose learning mechanism governing many complex behaviors including language acquisition. We recorded complex auditory brainstem responses (cABRs) while human adults implicitly learned to segment patterns embedded in an uninterrupted sound sequence based on their statistical characteristics. The brainstem's sensitivity to statistical structure was measured as the change in the cABR between a patterned and a pseudo-randomized sequence composed from the same set of sounds but differing in their sound-to-sound probabilities. Using this methodology, we provide the first demonstration that behavioral-indices of rapid learning relate to individual differences in brainstem physiology. We found that neural sensitivity to statistical structure manifested along a continuum, from adaptation to enhancement, where cABR enhancement (patterned>pseudo-random) tracked with greater rapid statistical learning than adaptation. Short- and long-term auditory experiences (days to years) are known to promote brainstem plasticity and here we provide a conceptual advance by showing that the brainstem is also integral to rapid learning occurring over minutes. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  7. Conceptual priming for realistic auditory scenes and for auditory words.

    Science.gov (United States)

    Frey, Aline; Aramaki, Mitsuko; Besson, Mireille

    2014-02-01

    Two experiments were conducted using both behavioral and Event-Related brain Potentials methods to examine conceptual priming effects for realistic auditory scenes and for auditory words. Prime and target sounds were presented in four stimulus combinations: Sound-Sound, Word-Sound, Sound-Word and Word-Word. Within each combination, targets were conceptually related to the prime, unrelated or ambiguous. In Experiment 1, participants were asked to judge whether the primes and targets fit together (explicit task) and in Experiment 2 they had to decide whether the target was typical or ambiguous (implicit task). In both experiments and in the four stimulus combinations, reaction times and/or error rates were longer/higher and the N400 component was larger to ambiguous targets than to conceptually related targets, thereby pointing to a common conceptual system for processing auditory scenes and linguistic stimuli in both explicit and implicit tasks. However, fine-grained analyses also revealed some differences between experiments and conditions in scalp topography and duration of the priming effects possibly reflecting differences in the integration of perceptual and cognitive attributes of linguistic and nonlinguistic sounds. These results have clear implications for the building-up of virtual environments that need to convey meaning without words. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Effect of hearing loss on semantic access by auditory and audiovisual speech in children.

    Science.gov (United States)

    Jerger, Susan; Tye-Murray, Nancy; Damian, Markus F; Abdi, Hervé

    2013-01-01

    This research studied whether the mode of input (auditory versus audiovisual) influenced semantic access by speech in children with sensorineural hearing impairment (HI). Participants, 31 children with HI and 62 children with normal hearing (NH), were tested with the authors' new multimodal picture word task. Children were instructed to name pictures displayed on a monitor and ignore auditory or audiovisual speech distractors. The semantic content of the distractors was varied to be related versus unrelated to the pictures (e.g., picture distractor of dog-bear versus dog-cheese, respectively). In children with NH, picture-naming times were slower in the presence of semantically related distractors. This slowing, called semantic interference, is attributed to the meaning-related picture-distractor entries competing for selection and control of the response (the lexical selection by competition hypothesis). Recently, a modification of the lexical selection by competition hypothesis, called the competition threshold (CT) hypothesis, proposed that (1) the competition between the picture-distractor entries is determined by a threshold, and (2) distractors with experimentally reduced fidelity cannot reach the CT. Thus, semantically related distractors with reduced fidelity do not produce the normal interference effect, but instead no effect or semantic facilitation (faster picture naming times for semantically related versus unrelated distractors). Facilitation occurs because the activation level of the semantically related distractor with reduced fidelity (1) is not sufficient to exceed the CT and produce interference but (2) is sufficient to activate its concept, which then strengthens the activation of the picture and facilitates naming. This research investigated whether the proposals of the CT hypothesis generalize to the auditory domain, to the natural degradation of speech due to HI, and to participants who are children. Our multimodal picture word task allowed us

  9. MS-27THE IMPACT OF HYPOFRACTIONATED LINAC-BASED STEREOTACTIC RADIOSURGERY UPON EARLY AUDITORY FUNCTIONS IN THE TREATMENT OF VESTIBULAR SCHWANNOMAS

    OpenAIRE

    Wang, Fen; Roy, Amit; Badkul, Rajeev; John, Park; Kumar, Parvesh; Staecker, Hinrich

    2014-01-01

    PURPOSE: To determine the impact of hypofractionated stereotactic radiotherapy (fSRT) scheme upon early auditory functions in the treatment of vestibular schwannomas (VSs). MATERIALS AND METHODS: 21 VS patients treated with a Linac-based frameless fSRT to 25 Gy in 5 daily fractions were retrospectively reviewed. Serial audiometry tests including auditory thresholds and speech discrimination (SD) were conducted prior to fSRT and then at regular intervals post-fSRT to determine the impact of ou...

  10. Adaptation in the auditory system: an overview

    Directory of Open Access Journals (Sweden)

    David ePérez-González

    2014-02-01

    Full Text Available The early stages of the auditory system need to preserve the timing information of sounds in order to extract the basic features of acoustic stimuli. At the same time, different processes of neuronal adaptation occur at several levels to further process the auditory information. For instance, auditory nerve fiber responses already experience adaptation of their firing rates, a type of response that can be found in many other auditory nuclei and may be useful for emphasizing the onset of the stimuli. However, it is at higher levels in the auditory hierarchy where more sophisticated types of neuronal processing take place. For example, stimulus-specific adaptation, where neurons show adaptation to frequent, repetitive stimuli, but maintain their responsiveness to stimuli with different physical characteristics, thus representing a distinct kind of processing that may play a role in change and deviance detection. In the auditory cortex, adaptation takes more elaborate forms, and contributes to the processing of complex sequences, auditory scene analysis and attention. Here we review the multiple types of adaptation that occur in the auditory system, which are part of the pool of resources that the neurons employ to process the auditory scene, and are critical to a proper understanding of the neuronal mechanisms that govern auditory perception.

  11. Auditory Dysfunction in Patients with Cerebrovascular Disease

    Directory of Open Access Journals (Sweden)

    Sadaharu Tabuchi

    2014-01-01

    Full Text Available Auditory dysfunction is a common clinical symptom that can induce profound effects on the quality of life of those affected. Cerebrovascular disease (CVD is the most prevalent neurological disorder today, but it has generally been considered a rare cause of auditory dysfunction. However, a substantial proportion of patients with stroke might have auditory dysfunction that has been underestimated due to difficulties with evaluation. The present study reviews relationships between auditory dysfunction and types of CVD including cerebral infarction, intracerebral hemorrhage, subarachnoid hemorrhage, cerebrovascular malformation, moyamoya disease, and superficial siderosis. Recent advances in the etiology, anatomy, and strategies to diagnose and treat these conditions are described. The numbers of patients with CVD accompanied by auditory dysfunction will increase as the population ages. Cerebrovascular diseases often include the auditory system, resulting in various types of auditory dysfunctions, such as unilateral or bilateral deafness, cortical deafness, pure word deafness, auditory agnosia, and auditory hallucinations, some of which are subtle and can only be detected by precise psychoacoustic and electrophysiological testing. The contribution of CVD to auditory dysfunction needs to be understood because CVD can be fatal if overlooked.

  12. Probabilistic Threshold Criterion

    Energy Technology Data Exchange (ETDEWEB)

    Gresshoff, M; Hrousis, C A

    2010-03-09

    The Probabilistic Shock Threshold Criterion (PSTC) Project at LLNL develops phenomenological criteria for estimating safety or performance margin on high explosive (HE) initiation in the shock initiation regime, creating tools for safety assessment and design of initiation systems and HE trains in general. Until recently, there has been little foundation for probabilistic assessment of HE initiation scenarios. This work attempts to use probabilistic information that is available from both historic and ongoing tests to develop a basis for such assessment. Current PSTC approaches start with the functional form of the James Initiation Criterion as a backbone, and generalize to include varying areas of initiation and provide a probabilistic response based on test data for 1.8 g/cc (Ultrafine) 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and LX-17 (92.5% TATB, 7.5% Kel-F 800 binder). Application of the PSTC methodology is presented investigating the safety and performance of a flying plate detonator and the margin of an Ultrafine TATB booster initiating LX-17.

  13. Reality of auditory verbal hallucinations.

    Science.gov (United States)

    Raij, Tuukka T; Valkonen-Korhonen, Minna; Holi, Matti; Therman, Sebastian; Lehtonen, Johannes; Hari, Riitta

    2009-11-01

    Distortion of the sense of reality, actualized in delusions and hallucinations, is the key feature of psychosis but the underlying neuronal correlates remain largely unknown. We studied 11 highly functioning subjects with schizophrenia or schizoaffective disorder while they rated the reality of auditory verbal hallucinations (AVH) during functional magnetic resonance imaging (fMRI). The subjective reality of AVH correlated strongly and specifically with the hallucination-related activation strength of the inferior frontal gyri (IFG), including the Broca's language region. Furthermore, how real the hallucination that subjects experienced was depended on the hallucination-related coupling between the IFG, the ventral striatum, the auditory cortex, the right posterior temporal lobe, and the cingulate cortex. Our findings suggest that the subjective reality of AVH is related to motor mechanisms of speech comprehension, with contributions from sensory and salience-detection-related brain regions as well as circuitries related to self-monitoring and the experience of agency.

  14. Learning foraging thresholds for lizards

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, L.A. [Univ. of Warwick, Coventry (United Kingdom). Dept. of Computer Science; Hart, W.E. [Sandia National Labs., Albuquerque, NM (United States); Wilson, D.B. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

    1996-01-12

    This work gives a proof of convergence for a randomized learning algorithm that describes how anoles (lizards found in the Carribean) learn a foraging threshold distance. This model assumes that an anole will pursue a prey if and only if it is within this threshold of the anole`s perch. This learning algorithm was proposed by the biologist Roughgarden and his colleagues. They experimentally confirmed that this algorithm quickly converges to the foraging threshold that is predicted by optimal foraging theory our analysis provides an analytic confirmation that the learning algorithm converses to this optimal foraging threshold with high probability.

  15. Albania - Thresholds I and II

    Data.gov (United States)

    Millennium Challenge Corporation — From 2006 to 2011, the government of Albania (GOA) received two Millennium Challenge Corporation (MCC) Threshold Programs totaling $29.6 million. Albania received...

  16. Perception of Complex Auditory Patterns.

    Science.gov (United States)

    1987-11-02

    and Piercy, M. (1973). Defects of non - verbal auditory perception in children with developmental aphasia . Nature (London), 241, 468-469. Watson, C.S...LII, zS 4p ETV I Hearing and Communication Laboratory Department of Speech and Hearing Sciences 7 Indiana University Bloomington, Indiana 47405 Final...Technical Report Air Force Office of Scientific Research AFOSR-84-0337 September 1, 1984 to August 31, 1987 Hearing and Communication Laboratory

  17. Auditory based neuropsychology in neurosurgery.

    Science.gov (United States)

    Wester, Knut

    2008-04-01

    In this article, an account is given on the author's experience with auditory based neuropsychology in a clinical, neurosurgical setting. The patients that were included in the studies are patients with traumatic or vascular brain lesions, patients undergoing brain surgery to alleviate symptoms of Parkinson's disease, or patients harbouring an intracranial arachnoid cyst affecting the temporal or the frontal lobe. The aims of these investigations were to collect information about the location of cognitive processes in the human brain, or to disclose dyscognition in patients with an arachnoid cyst. All the patients were tested with the DL technique. In addition, the cyst patients were subjected to a number of non-auditory, standard neuropsychological tests, such as Benton Visual Retention Test, Street Gestalt Test, Stroop Test and Trails Test A and B. The neuropsychological tests revealed that arachnoid cysts in general cause dyscognition that also includes auditory processes, and more importantly, that these cognition deficits normalise after surgical removal of the cyst. These observations constitute strong evidence in favour of surgical decompression.

  18. Auditory brainstem implant program development.

    Science.gov (United States)

    Schwartz, Marc S; Wilkinson, Eric P

    2017-08-01

    Auditory brainstem implants (ABIs), which have previously been used to restore auditory perception to deaf patients with neurofibromatosis type 2 (NF2), are now being utilized in other situations, including treatment of congenitally deaf children with cochlear malformations or cochlear nerve deficiencies. Concurrent with this expansion of indications, the number of centers placing and expressing interest in placing ABIs has proliferated. Because ABI placement involves posterior fossa craniotomy in order to access the site of implantation on the cochlear nucleus complex of the brainstem and is not without significant risk, we aim to highlight issues important in developing and maintaining successful ABI programs that would be in the best interests of patients. Especially with pediatric patients, the ultimate benefits of implantation will be known only after years of growth and development. These benefits have yet to be fully elucidated and continue to be an area of controversy. The limited number of publications in this area were reviewed. Review of the current literature was performed. Disease processes, risk/benefit analyses, degrees of evidence, and U.S. Food and Drug Administration approvals differ among various categories of patients in whom auditory brainstem implantation could be considered for use. We suggest sets of criteria necessary for the development of successful and sustaining ABI programs, including programs for NF2 patients, postlingually deafened adult nonneurofibromatosis type 2 patients, and congenitally deaf pediatric patients. Laryngoscope, 127:1909-1915, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  19. Assessment of an ICA-based noise reduction method for multi-channel auditory evoked potentials

    Science.gov (United States)

    Mirahmadizoghi, Siavash; Bell, Steven; Simpson, David

    2015-03-01

    In this work a new independent component analysis (ICA) based method for noise reduction in evoked potentials is evaluated on for auditory late responses (ALR) captured with a 63-channel electroencephalogram (EEG) from 10 normal-hearing subjects. The performance of the new method is compared with a single channel alternative in terms of signal to noise ratio (SNR), the number of channels with an SNR above an empirically derived statistical critical value and an estimate of hearing threshold. The results show that the multichannel signal processing method can significantly enhance the quality of the signal and also detected hearing thresholds significantly lower than with the single channel alternative.

  20. Auditory Sensitivity and Masking Profiles for the Sea Otter (Enhydra lutris).

    Science.gov (United States)

    Ghoul, Asila; Reichmuth, Colleen

    2016-01-01

    Sea otters are threatened marine mammals that may be negatively impacted by human-generated coastal noise, yet information about sound reception in this species is surprisingly scarce. We investigated amphibious hearing in sea otters by obtaining the first measurements of absolute sensitivity and critical masking ratios. Auditory thresholds were measured in air and underwater from 0.125 to 40 kHz. Critical ratios derived from aerial masked thresholds from 0.25 to 22.6 kHz were also obtained. These data indicate that although sea otters can detect underwater sounds, their hearing appears to be primarily air adapted and not specialized for detecting signals in background noise.

  1. Combined auditory and visual stimuli facilitate head saccades in the barn owl (Tyto alba).

    Science.gov (United States)

    Whitchurch, Elizabeth A; Takahashi, Terry T

    2006-08-01

    The barn owl naturally responds to an auditory or visual stimulus in its environment with a quick head turn toward the source. We measured these head saccades evoked by auditory, visual, and simultaneous, co-localized audiovisual stimuli to quantify multisensory interactions in the barn owl. Stimulus levels ranged from near to well above saccadic threshold. In accordance with previous human psychophysical findings, the owl's saccade reaction times (SRTs) and errors to unisensory stimuli were inversely related to stimulus strength. Auditory saccades characteristically had shorter reaction times but were less accurate than visual saccades. Audiovisual trials, over a large range of tested stimulus combinations, had auditory-like SRTs and visual-like errors, suggesting that barn owls are able to use both auditory and visual cues to produce saccades with the shortest possible SRT and greatest accuracy. These results support a model of sensory integration in which the faster modality initiates the saccade and the slower modality remains available to refine saccade trajectory.

  2. Differential responses of primary auditory cortex in autistic spectrum disorder with auditory hypersensitivity.

    Science.gov (United States)

    Matsuzaki, Junko; Kagitani-Shimono, Kuriko; Goto, Tetsu; Sanefuji, Wakako; Yamamoto, Tomoka; Sakai, Saeko; Uchida, Hiroyuki; Hirata, Masayuki; Mohri, Ikuko; Yorifuji, Shiro; Taniike, Masako

    2012-01-25

    The aim of this study was to investigate the differential responses of the primary auditory cortex to auditory stimuli in autistic spectrum disorder with or without auditory hypersensitivity. Auditory-evoked field values were obtained from 18 boys (nine with and nine without auditory hypersensitivity) with autistic spectrum disorder and 12 age-matched controls. Autistic disorder with hypersensitivity showed significantly more delayed M50/M100 peak latencies than autistic disorder without hypersensitivity or the control. M50 dipole moments in the hypersensitivity group were larger than those in the other two groups [corrected]. M50/M100 peak latencies were correlated with the severity of auditory hypersensitivity; furthermore, severe hypersensitivity induced more behavioral problems. This study indicates auditory hypersensitivity in autistic spectrum disorder as a characteristic response of the primary auditory cortex, possibly resulting from neurological immaturity or functional abnormalities in it. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.

  3. Pure word deafness with auditory object agnosia after bilateral lesion of the superior temporal sulcus.

    Science.gov (United States)

    Gutschalk, Alexander; Uppenkamp, Stefan; Riedel, Bernhard; Bartsch, Andreas; Brandt, Tobias; Vogt-Schaden, Marlies

    2015-12-01

    Based on results from functional imaging, cortex along the superior temporal sulcus (STS) has been suggested to subserve phoneme and pre-lexical speech perception. For vowel classification, both superior temporal plane (STP) and STS areas have been suggested relevant. Lesion of bilateral STS may conversely be expected to cause pure word deafness and possibly also impaired vowel classification. Here we studied a patient with bilateral STS lesions caused by ischemic strokes and relatively intact medial STPs to characterize the behavioral consequences of STS loss. The patient showed severe deficits in auditory speech perception, whereas his speech production was fluent and communication by written speech was grossly intact. Auditory-evoked fields in the STP were within normal limits on both sides, suggesting that major parts of the auditory cortex were functionally intact. Further studies showed that the patient had normal hearing thresholds and only mild disability in tests for telencephalic hearing disorder. Prominent deficits were discovered in an auditory-object classification task, where the patient performed four standard deviations below the control group. In marked contrast, performance in a vowel-classification task was intact. Auditory evoked fields showed enhanced responses for vowels compared to matched non-vowels within normal limits. Our results are consistent with the notion that cortex along STS is important for auditory speech perception, although it does not appear to be entirely speech specific. Formant analysis and single vowel classification, however, appear to be already implemented in auditory cortex on the STP. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Nanofibrous scaffolds for the guidance of stem cell-derived neurons for auditory nerve regeneration.

    Directory of Open Access Journals (Sweden)

    Sandra Hackelberg

    Full Text Available Impairment of spiral ganglion neurons (SGNs of the auditory nerve is a major cause for hearing loss occurring independently or in addition to sensory hair cell damage. Unfortunately, mammalian SGNs lack the potential for autonomous regeneration. Stem cell based therapy is a promising approach for auditory nerve regeneration, but proper integration of exogenous cells into the auditory circuit remains a fundamental challenge. Here, we present novel nanofibrous scaffolds designed to guide the integration of human stem cell-derived neurons in the internal auditory meatus (IAM, the foramen allowing passage of the spiral ganglion to the auditory brainstem. Human embryonic stem cells (hESC were differentiated into neural precursor cells (NPCs and seeded onto aligned nanofiber mats. The NPCs terminally differentiated into glutamatergic neurons with high efficiency, and neurite projections aligned with nanofibers in vitro. Scaffolds were assembled by seeding GFP-labeled NPCs on nanofibers integrated in a polymer sheath. Biocompatibility and functionality of the NPC-seeded scaffolds were evaluated in vivo in deafened guinea pigs (Cavia porcellus. To this end, we established an ouabain-based deafening procedure that depleted an average 72% of SGNs from apex to base of the cochleae and caused profound hearing loss. Further, we developed a surgical procedure to implant seeded scaffolds directly into the guinea pig IAM. No evidence of an inflammatory response was observed, but post-surgery tissue repair appeared to be facilitated by infiltrating Schwann cells. While NPC survival was found to be poor, both subjects implanted with NPC-seeded and cell-free control scaffolds showed partial recovery of electrically-evoked auditory brainstem thresholds. Thus, while future studies must address cell survival, nanofibrous scaffolds pose a promising strategy for auditory nerve regeneration.

  5. Loss of central auditory processing in a mouse model of Canavan disease.

    Directory of Open Access Journals (Sweden)

    Georg von Jonquieres

    Full Text Available Canavan Disease (CD is a leukodystrophy caused by homozygous null mutations in the gene encoding aspartoacylase (ASPA. ASPA-deficiency is characterized by severe psychomotor retardation, and excessive levels of the ASPA substrate N-acetylaspartate (NAA. ASPA is an oligodendrocyte marker and it is believed that CD has a central etiology. However, ASPA is also expressed by Schwann cells and ASPA-deficiency in the periphery might therefore contribute to the complex CD pathology. In this study, we assessed peripheral and central auditory function in the AspalacZ/lacZ rodent model of CD using auditory brainstem response (ABR. Increased ABR thresholds and the virtual loss of waveform peaks 4 and 5 from AspalacZ/lacZ mice, indicated altered central auditory processing in mutant mice compared with Aspawt/wt controls and altered central auditory processing. Analysis of ABR latencies recorded from AspalacZ/lacZ mice revealed that the speed of nerve conduction was unchanged in the peripheral part of the auditory pathway, and impaired in the CNS. Histological analyses confirmed that ASPA was expressed in oligodendrocytes and Schwann cells of the auditory system. In keeping with our physiological results, the cellular organization of the cochlea, including the organ of Corti, was preserved and the spiral ganglion nerve fibres were normal in ASPA-deficient mice. In contrast, we detected substantial hypomyelination in the central auditory system of AspalacZ/lacZ mice. In summary, our data suggest that the lack of ASPA in the CNS is responsible for the observed hearing deficits, while ASPA-deficiency in the cochlear nerve fibres is tolerated both morphologically and functionally.

  6. Loss of central auditory processing in a mouse model of Canavan disease.

    Science.gov (United States)

    von Jonquieres, Georg; Froud, Kristina E; Klugmann, Claudia B; Wong, Ann C Y; Housley, Gary D; Klugmann, Matthias

    2014-01-01

    Canavan Disease (CD) is a leukodystrophy caused by homozygous null mutations in the gene encoding aspartoacylase (ASPA). ASPA-deficiency is characterized by severe psychomotor retardation, and excessive levels of the ASPA substrate N-acetylaspartate (NAA). ASPA is an oligodendrocyte marker and it is believed that CD has a central etiology. However, ASPA is also expressed by Schwann cells and ASPA-deficiency in the periphery might therefore contribute to the complex CD pathology. In this study, we assessed peripheral and central auditory function in the AspalacZ/lacZ rodent model of CD using auditory brainstem response (ABR). Increased ABR thresholds and the virtual loss of waveform peaks 4 and 5 from AspalacZ/lacZ mice, indicated altered central auditory processing in mutant mice compared with Aspawt/wt controls and altered central auditory processing. Analysis of ABR latencies recorded from AspalacZ/lacZ mice revealed that the speed of nerve conduction was unchanged in the peripheral part of the auditory pathway, and impaired in the CNS. Histological analyses confirmed that ASPA was expressed in oligodendrocytes and Schwann cells of the auditory system. In keeping with our physiological results, the cellular organization of the cochlea, including the organ of Corti, was preserved and the spiral ganglion nerve fibres were normal in ASPA-deficient mice. In contrast, we detected substantial hypomyelination in the central auditory system of AspalacZ/lacZ mice. In summary, our data suggest that the lack of ASPA in the CNS is responsible for the observed hearing deficits, while ASPA-deficiency in the cochlear nerve fibres is tolerated both morphologically and functionally.

  7. Noise-induced cell death in the mouse medial geniculate body and primary auditory cortex.

    Science.gov (United States)

    Basta, Dietmar; Tzschentke, Barbara; Ernst, Arne

    Noise-induced effects within the inner ear have been well investigated for several years. However, this peripheral damage cannot fully explain the audiological symptoms in noise-induced hearing loss (NIHL), e.g. tinnitus, recruitment, reduced speech intelligibility, hyperacusis. There are few reports on central noise effects. Noise can induce an apoptosis of neuronal tissue within the lower auditory pathway. Higher auditory structures (e.g. medial geniculate body, auditory cortex) are characterized by metabolic changes after noise exposure. However, little is known about the microstructural changes of the higher auditory pathway after noise exposure. The present paper was therefore aimed at investigating the cell density in the medial geniculate body (MGB) and the primary auditory cortex (AI) after noise exposure. Normal hearing mice were exposed to noise (10 kHz center frequency at 115 dB SPL for 3 h) at the age of 21 days under anesthesia (Ketamin/Rompun, 10:1). After 1 week, auditory brainstem response recordings (ABR) were performed in noise exposed and normal hearing animals. After fixation, the brain was microdissected and stained (Kluever-Barrera). The cell density in the MGB subdivisions and the AI were determined by counting the cells within a grid. Noise-exposed animals showed a significant ABR threshold shift over the whole frequency range. Cell density was significantly reduced in all subdivisions of the MGB and in layers IV-VI of AI. The present findings demonstrate a significant noise-induced change of the neuronal cytoarchitecture in central key areas of auditory processing. These changes could contribute to the complex psychoacoustic symptoms after NIHL.

  8. Auditory neuropathy/Auditory dyssynchrony - An underdiagnosed condition: A case report with review of literature

    OpenAIRE

    Vinish Agarwal; Saurabh Varshney; Sampan Singh Bist; Sanjiv Bhagat; Sarita Mishra; Vivek Jha

    2012-01-01

    Auditory neuropathy (AN)/auditory dyssynchrony (AD) is a very often missed diagnosis, hence an underdiagnosed condition in clinical practice. Auditory neuropathy is a condition in which patients, on audiologic evaluation, are found to have normal outer hair cell function and abnormal neural function at the level of the eighth nerve. These patients, on clinical testing, are found to have normal otoacoustic emissions, whereas auditory brainstem response audiometry reveals the absence of neural ...

  9. Percolation thresholds on elongated lattices

    NARCIS (Netherlands)

    Marrink, S.J.; Knackstedt, Mark A.

    1999-01-01

    We investigate the percolation thresholds of both random and invasion percolation in two and three dimensions on elongated lattices; lattices with a geometry of L^(d−1) × nL in d dimensions, where n denotes the aspect ratio of the lattice. Scaling laws for the threshold and spanning cluster density

  10. Threshold Hypothesis: Fact or Artifact?

    Science.gov (United States)

    Karwowski, Maciej; Gralewski, Jacek

    2013-01-01

    The threshold hypothesis (TH) assumes the existence of complex relations between creative abilities and intelligence: linear associations below 120 points of IQ and weaker or lack of associations above the threshold. However, diverse results have been obtained over the last six decades--some confirmed the hypothesis and some rejected it. In this…

  11. Threshold Concepts and Information Literacy

    Science.gov (United States)

    Townsend, Lori; Brunetti, Korey; Hofer, Amy R.

    2011-01-01

    What do we teach when we teach information literacy in higher education? This paper describes a pedagogical approach to information literacy that helps instructors focus content around transformative learning thresholds. The threshold concept framework holds promise for librarians because it grounds the instructor in the big ideas and underlying…

  12. Random Gap Detection Test (RGDT) performance of individuals with central auditory processing disorders from 5 to 25 years of age.

    Science.gov (United States)

    Dias, Karin Ziliotto; Jutras, Benoît; Acrani, Isabela Olszanski; Pereira, Liliane Desgualdo

    2012-02-01

    The aim of the present study was to assess the auditory temporal resolution ability in individuals with central auditory processing disorders, to examine the maturation effect and to investigate the relationship between the performance on a temporal resolution test with the performance on other central auditory tests. Participants were divided in two groups: 131 with Central Auditory Processing Disorder and 94 with normal auditory processing. They had pure-tone air-conduction thresholds no poorer than 15 dB HL bilaterally, normal admittance measures and presence of acoustic reflexes. Also, they were assessed with a central auditory test battery. Participants who failed at least one or more tests were included in the Central Auditory Processing Disorder group and those in the control group obtained normal performance on all tests. Following the auditory processing assessment, the Random Gap Detection Test was administered to the participants. A three-way ANOVA was performed. Correlation analyses were also done between the four Random Gap Detection Test subtests data as well as between Random Gap Detection Test data and the other auditory processing test results. There was a significant difference between the age-group performances in children with and without Central Auditory Processing Disorder. Also, 48% of children with Central Auditory Processing Disorder failed the Random Gap Detection Test and the percentage decreased as a function of age. The highest percentage (86%) was found in the 5-6 year-old children. Furthermore, results revealed a strong significant correlation between the four Random Gap Detection Test subtests. There was a modest correlation between the Random Gap Detection Test results and the dichotic listening tests. No significant correlation was observed between the Random Gap Detection Test data and the results of the other tests in the battery. Random Gap Detection Test should not be administered to children younger than 7 years old because

  13. The Identification and Remediation of Auditory Problems

    Science.gov (United States)

    Kottler, Sylvia B.

    1972-01-01

    Procedures and sample activities are provided for both identifying and training children with auditory perception problems related to sound localization, sound discrimination, and sound sequencing. (KW)

  14. Human Factors Military Lexicon: Auditory Displays

    National Research Council Canada - National Science Library

    Letowski, Tomasz

    2001-01-01

    .... In addition to definitions specific to auditory displays, speech communication, and audio technology, the lexicon includes several terms unique to military operational environments and human factors...

  15. Developing Auditory Measures of General Speediness

    Directory of Open Access Journals (Sweden)

    Ian T. Zajac

    2011-10-01

    Full Text Available This study examined whether the broad ability general speediness (Gs could be measured via the auditory modality. Existing and purpose-developed auditory tasks that maintained the cognitive requirements of established visually presented Gs markers were completed by 96 university undergraduates. Exploratory and confirmatory factor analyses showed that the auditory tasks combined with established visual measures to define latent Gs and reaction time factors. These findings provide preliminary evidence that suggests that if auditory tasks are developed that maintain the same cognitive requirements as existing visual measures, then they are likely to index similar cognitive processes.

  16. Auditory, visual and auditory-visual memory and sequencing performance in typically developing children.

    Science.gov (United States)

    Pillai, Roshni; Yathiraj, Asha

    2017-09-01

    The study evaluated whether there exists a difference/relation in the way four different memory skills (memory score, sequencing score, memory span, & sequencing span) are processed through the auditory modality, visual modality and combined modalities. Four memory skills were evaluated on 30 typically developing children aged 7 years and 8 years across three modality conditions (auditory, visual, & auditory-visual). Analogous auditory and visual stimuli were presented to evaluate the three modality conditions across the two age groups. The children obtained significantly higher memory scores through the auditory modality compared to the visual modality. Likewise, their memory scores were significantly higher through the auditory-visual modality condition than through the visual modality. However, no effect of modality was observed on the sequencing scores as well as for the memory and the sequencing span. A good agreement was seen between the different modality conditions that were studied (auditory, visual, & auditory-visual) for the different memory skills measures (memory scores, sequencing scores, memory span, & sequencing span). A relatively lower agreement was noted only between the auditory and visual modalities as well as between the visual and auditory-visual modality conditions for the memory scores, measured using Bland-Altman plots. The study highlights the efficacy of using analogous stimuli to assess the auditory, visual as well as combined modalities. The study supports the view that the performance of children on different memory skills was better through the auditory modality compared to the visual modality. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Seeing the song: left auditory structures may track auditory-visual dynamic alignment.

    Directory of Open Access Journals (Sweden)

    Julia A Mossbridge

    Full Text Available Auditory and visual signals generated by a single source tend to be temporally correlated, such as the synchronous sounds of footsteps and the limb movements of a walker. Continuous tracking and comparison of the dynamics of auditory-visual streams is thus useful for the perceptual binding of information arising from a common source. Although language-related mechanisms have been implicated in the tracking of speech-related auditory-visual signals (e.g., speech sounds and lip movements, it is not well known what sensory mechanisms generally track ongoing auditory-visual synchrony for non-speech signals in a complex auditory-visual environment. To begin to address this question, we used music and visual displays that varied in the dynamics of multiple features (e.g., auditory loudness and pitch; visual luminance, color, size, motion, and organization across multiple time scales. Auditory activity (monitored using auditory steady-state responses, ASSR was selectively reduced in the left hemisphere when the music and dynamic visual displays were temporally misaligned. Importantly, ASSR was not affected when attentional engagement with the music was reduced, or when visual displays presented dynamics clearly dissimilar to the music. These results appear to suggest that left-lateralized auditory mechanisms are sensitive to auditory-visual temporal alignment, but perhaps only when the dynamics of auditory and visual streams are similar. These mechanisms may contribute to correct auditory-visual binding in a busy sensory environment.

  18. Auditory Processing Disorders (APD): a distinct clinical disorder or not?

    NARCIS (Netherlands)

    Ellen de Wit

    2015-01-01

    Presentatie CPLOL congres Florence In this systematic review, six electronic databases were searched for peer-reviewed studies using the key words auditory processing, auditory diseases, central [Mesh], and auditory perceptual. Two reviewers independently assessed relevant studies by inclusion

  19. Computational Auditory Scene Analysis Based Perceptual and Neural Principles

    National Research Council Canada - National Science Library

    Wang, DeLiang

    2004-01-01

    .... This fundamental process of auditory perception is called auditory scene analysis. of particular importance in auditory scene analysis is the separation of speech from interfering sounds, or speech segregation...

  20. Stuttering adults' lack of pre-speech auditory modulation normalizes when speaking with delayed auditory feedback.

    Science.gov (United States)

    Daliri, Ayoub; Max, Ludo

    2018-02-01

    Auditory modulation during speech movement planning is limited in adults who stutter (AWS), but the functional relevance of the phenomenon itself remains unknown. We investigated for AWS and adults who do not stutter (AWNS) (a) a potential relationship between pre-speech auditory modulation and auditory feedback contributions to speech motor learning and (b) the effect on pre-speech auditory modulation of real-time versus delayed auditory feedback. Experiment I used a sensorimotor adaptation paradigm to estimate auditory-motor speech learning. Using acoustic speech recordings, we quantified subjects' formant frequency adjustments across trials when continually exposed to formant-shifted auditory feedback. In Experiment II, we used electroencephalography to determine the same subjects' extent of pre-speech auditory modulation (reductions in auditory evoked potential N1 amplitude) when probe tones were delivered prior to speaking versus not speaking. To manipulate subjects' ability to monitor real-time feedback, we included speaking conditions with non-altered auditory feedback (NAF) and delayed auditory feedback (DAF). Experiment I showed that auditory-motor learning was limited for AWS versus AWNS, and the extent of learning was negatively correlated with stuttering frequency. Experiment II yielded several key findings: (a) our prior finding of limited pre-speech auditory modulation in AWS was replicated; (b) DAF caused a decrease in auditory modulation for most AWNS but an increase for most AWS; and (c) for AWS, the amount of auditory modulation when speaking with DAF was positively correlated with stuttering frequency. Lastly, AWNS showed no correlation between pre-speech auditory modulation (Experiment II) and extent of auditory-motor learning (Experiment I) whereas AWS showed a negative correlation between these measures. Thus, findings suggest that AWS show deficits in both pre-speech auditory modulation and auditory-motor learning; however, limited pre

  1. Accuracy of auditory steady state and auditory brainstem responses to detect the preventive effect of polyphenols on age-related hearing loss in Sprague-Dawley rats.

    Science.gov (United States)

    Sanz-Fernández, Ricardo; Sánchez-Rodriguez, Carolina; Granizo, José Juan; Durio-Calero, Enrique; Martín-Sanz, Eduardo

    2016-02-01

    Aging causes histological, electrophysiological and molecular changes in the cochlea. The free radical theory of aging, has obtained consensus, and the mitochondrion is reported to play a key role in aging as a major source of reactive oxygen species. In the last years, there has been a significant increase in the interest in polyphenols because of the antioxidant properties and their role in the prevention of various diseases associated with oxidative stress, including aging. The aim of this study was to evaluate the preventive effect of different polyphenols on ARHL with auditory-evoked potentials. 100 Healthy female Sprague-Dawley (SD) rats were used for this study. Five groups were created based on the age of the rats, in months: 3, 6, 12, 18 and 24 months old. Two additional groups were created based on the treatment received. In the control group, 50 animals were assigned to no treatment. In the treated group, 50 animals were given a vehicle mixture of polyphenols for the half of the life before euthanization. Nine frequencies were tested (0.5-16 kHz) with ASSR and tone-burst ABR, performed on all of the rats prior to sacrifice. 100-μs auditory clicks ABRs were also recorded. A significant decrease in the audition was detected with ABR and ASSR in both treated and non-treated groups, as the different groups became older. This deterioration was more accurately measured at acute frequencies. Significantly lower thresholds were observed in the treated rats in the 6, 12 and 18-month-old group in the treated rats compared with the control group. All of the thresholds elicited using the ASSR technique were lower than the thresholds obtained using the ABR, regardless of the stimulus type. The present study demonstrated the benefits of the polyphenols, which generated a significant protection against ARHL, with significantly improved ASSR and tone-burst ABR auditory thresholds in rats receiving treatment with polyphenols.

  2. Loss of auditory sensitivity from inner hair cell synaptopathy can be centrally compensated in the young but not old brain.

    Science.gov (United States)

    Möhrle, Dorit; Ni, Kun; Varakina, Ksenya; Bing, Dan; Lee, Sze Chim; Zimmermann, Ulrike; Knipper, Marlies; Rüttiger, Lukas

    2016-08-01

    A dramatic shift in societal demographics will lead to rapid growth in the number of older people with hearing deficits. Poorer performance in suprathreshold speech understanding and temporal processing with age has been previously linked with progressing inner hair cell (IHC) synaptopathy that precedes age-dependent elevation of auditory thresholds. We compared central sound responsiveness after acoustic trauma in young, middle-aged, and older rats. We demonstrate that IHC synaptopathy progresses from middle age onward and hearing threshold becomes elevated from old age onward. Interestingly, middle-aged animals could centrally compensate for the loss of auditory fiber activity through an increase in late auditory brainstem responses (late auditory brainstem response wave) linked to shortening of central response latencies. In contrast, old animals failed to restore central responsiveness, which correlated with reduced temporal resolution in responding to amplitude changes. These findings may suggest that cochlear IHC synaptopathy with age does not necessarily induce temporal auditory coding deficits, as long as the capacity to generate neuronal gain maintains normal sound-induced central amplitudes. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Parent report of the development of auditory skills in infants and toddlers who use hearing aids.

    Science.gov (United States)

    Ben-Itzhak, Drorit; Greenstein, Tally; Kishon-Rabin, Liat

    2014-01-01

    This study investigated the use of the Infant-Toddler Meaningful Auditory Integration Scale (IT-MAIS) as a measure of early auditory skill development in aided infants and toddlers with varying degrees of hearing loss. Specific goals were (1) to rate the change in IT-MAIS score as a function of change in hearing thresholds achieved through amplification; (2) to establish the hierarchy of early auditory skill development for infants who use hearing aids (HAs) relative to what is known in infants with normal hearing; and (3) to analyze background information variables that may account for differences in IT-MAIS performance, as age and duration of HAs use. The study included 106 infants and toddlers (47 girls and 59 boys) aged 7 to 36 months (mean = 19.02, SD = 7.7) with various degrees of sensorineural hearing loss (mean = 86.42 dB, SD = 22.52). Infants used bilateral digital HAs with a mean experience of 8 months. All participants attended the same early intervention program. After at least 2 months of HA use, parents were interviewed with the IT-MAIS questionnaire regarding the auditory behavior of their infants in everyday situations. The results of the present study support the following outcomes: (1) on average, every 10 dB gain in pure-tone average scores (PTA4) threshold improved the IT-MAIS score by 10%; (2) infants who were part of the same unaided hearing categories appeared to have derived different benefits from amplification; (3) when reaching the same aided category, those infants who were originally in a better unaided hearing category achieved higher IT-MAIS scores than those who belonged to a worse unaided hearing category; (4) the hierarchy of auditory development in young aided infants with hearing loss followed that of normal hearing peers; and (5) 62.9% of the variance of IT-MAIS performance was explained by aided hearing level (50.3%), unaided hearing level (6.4%), and duration of HA use (6.2)%. The present study provides important information

  4. Tonotopic organisation of the auditory cortex in sloping sensorineural hearing loss.

    Science.gov (United States)

    Wolak, Tomasz; Cieśla, Katarzyna; Lorens, Artur; Kochanek, Krzysztof; Lewandowska, Monika; Rusiniak, Mateusz; Pluta, Agnieszka; Wójcik, Joanna; Skarżyński, Henryk

    2017-11-01

    Although the tonotopic organisation of the human primary auditory cortex (PAC) has already been studied, the question how its responses are affected in sensorineural hearing loss remains open. Twenty six patients (aged 38.1 ± 9.1 years; 12 men) with symmetrical sloping sensorineural hearing loss (SNHL) and 32 age- and gender-matched controls (NH) participated in an fMRI study using a sparse protocol. The stimuli were binaural 8s complex tones with central frequencies of 400 HzCF, 800 HzCF, 1600 HzCF, 3200 HzCF, or 6400 HzCF, presented at 80 dB(C). In NH responses to all frequency ranges were found in bilateral auditory cortices. The outcomes of a winnermap approach, showing a relative arrangement of active frequency-specific areas, was in line with the existing literature and revealed a V-shape high-frequency gradient surrounding areas that responded to low frequencies in the auditory cortex. In SNHL frequency-specific auditory cortex responses were observed only for sounds from 400 HzCF to 1600 HzCF, due to the severe or profound hearing loss in higher frequency ranges. Using a stringent statistical threshold (p < 0.05; FWE) significant differences between NH and SNHL were only revealed for mid and high-frequency sounds. At a more lenient statistical threshold (p < 0.001, FDRc), however, the size of activation induced by 400 HzCF in PAC was found statistically larger in patients with a prelingual, as compared to a postlingual onset of hearing loss. In addition, this low-frequency range was more extensively represented in the auditory cortex when outcomes obtained in all patients were contrasted with those revealed in normal hearing individuals (although statistically significant only for the secondary auditory cortex). The outcomes of the study suggest preserved patterns of large-scale tonotopic organisation in SNHL which can be further refined following auditory experience, especially when the hearing loss occurs prelingually. SNHL can induce both

  5. Asymmetric transfer of auditory perceptual learning

    Directory of Open Access Journals (Sweden)

    Sygal eAmitay

    2012-11-01

    Full Text Available Perceptual skills can improve dramatically even with minimal practice. A major and practical benefit of learning, however, is in transferring the improvement on the trained task to untrained tasks or stimuli, yet the mechanisms underlying this process are still poorly understood. Reduction of internal noise has been proposed as a mechanism of perceptual learning, and while we have evidence that frequency discrimination (FD learning is due to a reduction of internal noise, the source of that noise was not determined. In this study, we examined whether reducing the noise associated with neural phase locking to tones can explain the observed improvement in behavioural thresholds. We compared FD training between two tone durations (15 and 100 ms that straddled the temporal integration window of auditory nerve fibers upon which computational modeling of phase locking noise was based. Training on short tones resulted in improved FD on probe tests of both the long and short tones. Training on long tones resulted in improvement only on the long tones. Simulations of FD learning, based on the computational model and on signal detection theory, were compared with the behavioral FD data. We found that improved fidelity of phase locking accurately predicted transfer of learning from short to long tones, but also predicted transfer from long to short tones. The observed lack of transfer from long to short tones suggests the involvement of a second mechanism. Training may have increased the temporal integration window which could not transfer because integration time for the short tone is limited by its duration. Current learning models assume complex relationships between neural populations that represent the trained stimuli. In contrast, we propose that training-induced enhancement of the signal-to-noise ratio offers a parsimonious explanation of learning and transfer that easily accounts for asymmetric transfer of learning.

  6. Auditory Association Cortex Lesions Impair Auditory Short-Term Memory in Monkeys

    Science.gov (United States)

    Colombo, Michael; D'Amato, Michael R.; Rodman, Hillary R.; Gross, Charles G.

    1990-01-01

    Monkeys that were trained to perform auditory and visual short-term memory tasks (delayed matching-to-sample) received lesions of the auditory association cortex in the superior temporal gyrus. Although visual memory was completely unaffected by the lesions, auditory memory was severely impaired. Despite this impairment, all monkeys could discriminate sounds closer in frequency than those used in the auditory memory task. This result suggests that the superior temporal cortex plays a role in auditory processing and retention similar to the role the inferior temporal cortex plays in visual processing and retention.

  7. Active Auditory Mechanics in Insects

    Science.gov (United States)

    Robert, D.; Göpfert, M. C.

    2003-02-01

    Evidence is presented that hearing in some insects is an active process. Audition in mosquitoes is used for mate-detection and is supported by antennal receivers, whose sound-induced vibrations are transduced by Johnston's organs. Each of these sensory organs contains ca. 15,000 sensory neurons. As shown by mechanical analysis, a physiologically vulnerable mechanism is at work that nonlinearly enhances the sensitivity and frequency selectivity of antennal hearing. This process of amplification correlates with the electrical activity of the auditory mechanoreceptor units in Johnston's organ.

  8. Primary Auditory Cortex Regulates Threat Memory Specificity

    Science.gov (United States)

    Wigestrand, Mattis B.; Schiff, Hillary C.; Fyhn, Marianne; LeDoux, Joseph E.; Sears, Robert M.

    2017-01-01

    Distinguishing threatening from nonthreatening stimuli is essential for survival and stimulus generalization is a hallmark of anxiety disorders. While auditory threat learning produces long-lasting plasticity in primary auditory cortex (Au1), it is not clear whether such Au1 plasticity regulates memory specificity or generalization. We used…

  9. Auditory Processing Disorder and Foreign Language Acquisition

    Science.gov (United States)

    Veselovska, Ganna

    2015-01-01

    This article aims at exploring various strategies for coping with the auditory processing disorder in the light of foreign language acquisition. The techniques relevant to dealing with the auditory processing disorder can be attributed to environmental and compensatory approaches. The environmental one involves actions directed at creating a…

  10. Further Evidence of Auditory Extinction in Aphasia

    Science.gov (United States)

    Marshall, Rebecca Shisler; Basilakos, Alexandra; Love-Myers, Kim

    2013-01-01

    Purpose: Preliminary research ( Shisler, 2005) suggests that auditory extinction in individuals with aphasia (IWA) may be connected to binding and attention. In this study, the authors expanded on previous findings on auditory extinction to determine the source of extinction deficits in IWA. Method: Seventeen IWA (M[subscript age] = 53.19 years)…

  11. [Symptoms and diagnosis of auditory processing disorder].

    Science.gov (United States)

    Keilmann, A; Läßig, A K; Nospes, S

    2013-08-01

    The definition of an auditory processing disorder (APD) is based on impairments of auditory functions. APDs are disturbances in processes central to hearing that cannot be explained by comorbidities such as attention deficit or language comprehension disorders. Symptoms include difficulties in differentiation and identification of changes in time, structure, frequency and intensity of sounds; problems with sound localization and lateralization, as well as poor speech comprehension in adverse listening environments and dichotic situations. According to the German definition of APD (as opposed to central auditory processing disorder, CAPD), peripheral hearing loss or cognitive impairment also exclude APD. The diagnostic methodology comprises auditory function tests and the required diagnosis of exclusion. APD is diagnosed if a patient's performance is two standard deviations below the normal mean in at least two areas of auditory processing. The treatment approach for an APD depends on the patient's particular deficits. Training, compensatory strategies and improvement of the listening conditions can all be effective.

  12. Looming biases in monkey auditory cortex.

    Science.gov (United States)

    Maier, Joost X; Ghazanfar, Asif A

    2007-04-11

    Looming signals (signals that indicate the rapid approach of objects) are behaviorally relevant signals for all animals. Accordingly, studies in primates (including humans) reveal attentional biases for detecting and responding to looming versus receding signals in both the auditory and visual domains. We investigated the neural representation of these dynamic signals in the lateral belt auditory cortex of rhesus monkeys. By recording local field potential and multiunit spiking activity while the subjects were presented with auditory looming and receding signals, we show here that auditory cortical activity was biased in magnitude toward looming versus receding stimuli. This directional preference was not attributable to the absolute intensity of the sounds nor can it be attributed to simple adaptation, because white noise stimuli with identical amplitude envelopes did not elicit the same pattern of responses. This asymmetrical representation of looming versus receding sounds in the lateral belt auditory cortex suggests that it is an important node in the neural network correlate of looming perception.

  13. Parton distributions with threshold resummation

    CERN Document Server

    Bonvini, Marco; Rojo, Juan; Rottoli, Luca; Ubiali, Maria; Ball, Richard D.; Bertone, Valerio; Carrazza, Stefano; Hartland, Nathan P.

    2015-01-01

    We construct a set of parton distribution functions (PDFs) in which fixed-order NLO and NNLO calculations are supplemented with soft-gluon (threshold) resummation up to NLL and NNLL accuracy respectively, suitable for use in conjunction with any QCD calculation in which threshold resummation is included at the level of partonic cross sections. These resummed PDF sets, based on the NNPDF3.0 analysis, are extracted from deep-inelastic scattering, Drell-Yan, and top quark pair production data, for which resummed calculations can be consistently used. We find that, close to threshold, the inclusion of resummed PDFs can partially compensate the enhancement in resummed matrix elements, leading to resummed hadronic cross-sections closer to the fixed-order calculation. On the other hand, far from threshold, resummed PDFs reduce to their fixed-order counterparts. Our results demonstrate the need for a consistent use of resummed PDFs in resummed calculations.

  14. Temporally selective processing of communication signals by auditory midbrain neurons

    DEFF Research Database (Denmark)

    Elliott, Taffeta M; Christensen-Dalsgaard, Jakob; Kelley, Darcy B

    2011-01-01

    of the rate of clicks in calls. The majority of neurons (85%) were selective for click rates, and this selectivity remained unchanged over sound levels 10 to 20 dB above threshold. Selective neurons give phasic, tonic, or adapting responses to tone bursts and click trains. Some algorithms that could compute...... of auditory neurons in the laminar nucleus of the torus semicircularis (TS) of X. laevis specializes in encoding vocalization click rates. We recorded single TS units while pure tones, natural calls, and synthetic clicks were presented directly to the tympanum via a vibration-stimulation probe. Synthesized...... click rates ranged from 4 to 50 Hz, the rate at which the clicks begin to overlap. Frequency selectivity and temporal processing were characterized using response-intensity curves, temporal-discharge patterns, and autocorrelations of reduplicated responses to click trains. Characteristic frequencies...

  15. PSYCHOACOUSTICS: a comprehensive MATLAB toolbox for auditory testing.

    Science.gov (United States)

    Soranzo, Alessandro; Grassi, Massimo

    2014-01-01

    PSYCHOACOUSTICS is a new MATLAB toolbox which implements three classic adaptive procedures for auditory threshold estimation. The first includes those of the Staircase family (method of limits, simple up-down and transformed up-down); the second is the Parameter Estimation by Sequential Testing (PEST); and the third is the Maximum Likelihood Procedure (MLP). The toolbox comes with more than twenty built-in experiments each provided with the recommended (default) parameters. However, if desired, these parameters can be modified through an intuitive and user friendly graphical interface and stored for future use (no programming skills are required). Finally, PSYCHOACOUSTICS is very flexible as it comes with several signal generators and can be easily extended for any experiment.

  16. A test battery measuring auditory capabilities of listening panels

    DEFF Research Database (Denmark)

    Ghani, Jody; Ellermeier, Wolfgang; Zimmer, Karin

    2005-01-01

    a battery of tests covering a larger range of auditory capabilities in order to assess individual listeners. The format of all tests is kept as 'objective' as possible by using a three-alternative forced-choice paradigm in which the subject must choose which of the sound samples is different, thus keeping...... the instruction to the subjects simple and common for all tests. Both basic (e.g. frequency discrimination) and complex (e.g. profile analysis) psychoacoustic tests are covered in the battery and a threshold of discrimination or detection is obtained for each test. Data were collected on 24 listeners who had been...... recruited for participation in an expert listening panel for evaluating the sound quality of hi-fi audio systems. The test battery data were related to the actual performance of the listeners when judging the degradation in quality produced by audio codecs....

  17. PSYCHOACOUSTICS: a comprehensive MATLAB toolbox for auditory testing

    Directory of Open Access Journals (Sweden)

    Alessandro eSoranzo

    2014-07-01

    Full Text Available PSYCHOACOUSTICS is a new MATLAB toolbox which implements three classic adaptive procedures for auditory threshold estimation. The first includes those of the Staircase family (method of limits, simple up-down and transformed up-down; the second is the Parameter Estimation by Sequential Testing (PEST; and the third is the Maximum Likelihood Procedure (MLP. The toolbox comes with more than twenty built-in experiments each provided with the recommended (default parameters. However, if desired, these parameters can be modified through an intuitive and user friendly graphical interface and stored for future use (no programming skills are required. Finally, PSYCHOACOUSTICS is very flexible as it comes with several signal generators and can be easily extended for any experiment.

  18. Auditory temporal processing in patients with temporal lobe epilepsy.

    Science.gov (United States)

    Lavasani, Azam Navaei; Mohammadkhani, Ghassem; Motamedi, Mahmoud; Karimi, Leyla Jalilvand; Jalaei, Shohreh; Shojaei, Fereshteh Sadat; Danesh, Ali; Azimi, Hadi

    2016-07-01

    Auditory temporal processing is the main feature of speech processing ability. Patients with temporal lobe epilepsy, despite their normal hearing sensitivity, may present speech recognition disorders. The present study was carried out to evaluate the auditory temporal processing in patients with unilateral TLE. The present study was carried out on 25 patients with epilepsy: 11 patients with right temporal lobe epilepsy and 14 with left temporal lobe epilepsy with a mean age of 31.1years and 18 control participants with a mean age of 29.4years. The two experimental and control groups were evaluated via gap-in-noise and duration pattern sequence tests. One-way ANOVA was run to analyze the data. The mean of the threshold of the GIN test in the control group was observed to be better than that in participants with LTLE and RTLE. Also, it was observed that the percentage of correct responses on the DPS test in the control group and in participants with RTLE was better than that in participants with LTLE. Patients with TLE have difficulties in temporal processing. Difficulties are more significant in patients with LTLE, likely because the left temporal lobe is specialized for the processing of temporal information. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Expression and function of scleraxis in the developing auditory system.

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    Zoe F Mann

    Full Text Available A study of genes expressed in the developing inner ear identified the bHLH transcription factor Scleraxis (Scx in the developing cochlea. Previous work has demonstrated an essential role for Scx in the differentiation and development of tendons, ligaments and cells of chondrogenic lineage. Expression in the cochlea has been shown previously, however the functional role for Scx in the cochlea is unknown. Using a Scx-GFP reporter mouse line we examined the spatial and temporal patterns of Scx expression in the developing cochlea between embryonic day 13.5 and postnatal day 25. Embryonically, Scx is expressed broadly throughout the cochlear duct and surrounding mesenchyme and at postnatal ages becomes restricted to the inner hair cells and the interdental cells of the spiral limbus. Deletion of Scx results in hearing impairment indicated by elevated auditory brainstem response (ABR thresholds and diminished distortion product otoacoustic emission (DPOAE amplitudes, across a range of frequencies. No changes in either gross cochlear morphology or expression of the Scx target genes Col2A, Bmp4 or Sox9 were observed in Scx(-/- mutants, suggesting that the auditory defects observed in these animals may be a result of unidentified Scx-dependent processes within the cochlea.

  20. Development of Brainstem-Evoked Responses in Congenital Auditory Deprivation

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    J. Tillein

    2012-01-01

    Full Text Available To compare the development of the auditory system in hearing and completely acoustically deprived animals, naive congenitally deaf white cats (CDCs and hearing controls (HCs were investigated at different developmental stages from birth till adulthood. The CDCs had no hearing experience before the acute experiment. In both groups of animals, responses to cochlear implant stimulation were acutely assessed. Electrically evoked auditory brainstem responses (E-ABRs were recorded with monopolar stimulation at different current levels. CDCs demonstrated extensive development of E-ABRs, from first signs of responses at postnatal (p.n. day 3 through appearance of all waves of brainstem response at day 8 p.n. to mature responses around day 90 p.n.. Wave I of E-ABRs could not be distinguished from the artifact in majority of CDCs, whereas in HCs, it was clearly separated from the stimulus artifact. Waves II, III, and IV demonstrated higher thresholds in CDCs, whereas this difference was not found for wave V. Amplitudes of wave III were significantly higher in HCs, whereas wave V amplitudes were significantly higher in CDCs. No differences in latencies were observed between the animal groups. These data demonstrate significant postnatal subcortical development in absence of hearing, and also divergent effects of deafness on early waves II–IV and wave V of the E-ABR.

  1. Brainstem Evoked Potential Indices of Subcortical Auditory Processing After Mild Traumatic Brain Injury.

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    Vander Werff, Kathy R; Rieger, Brian

    The primary aim of this study was to assess subcortical auditory processing in individuals with chronic symptoms after mild traumatic brain injury (mTBI) by measuring auditory brainstem responses (ABRs) to standard click and complex speech stimuli. Consistent with reports in the literature of auditory problems after mTBI (despite normal-hearing thresholds), it was hypothesized that individuals with mTBI would have evidence of impaired neural encoding in the auditory brainstem compared to noninjured controls, as evidenced by delayed latencies and reduced amplitudes of ABR components. We further hypothesized that the speech-evoked ABR would be more sensitive than the click-evoked ABR to group differences because of its complex nature, particularly when recorded in a background noise condition. Click- and speech-ABRs were collected in 32 individuals diagnosed with mTBI in the past 3 to 18 months. All mTBI participants were experiencing ongoing injury symptoms for which they were seeking rehabilitation through a brain injury rehabilitation management program. The same data were collected in a group of 32 age- and gender-matched controls with no history of head injury. ABRs were recorded in both left and right ears for all participants in all conditions. Speech-ABRs were collected in both quiet and in a background of continuous 20-talker babble ipsilateral noise. Peak latencies and amplitudes were compared between groups and across subgroups of mTBI participants categorized by their behavioral auditory test performance. Click-ABR results were not significantly different between the mTBI and control groups. However, when comparing the control group to only those mTBI subjects with measurably decreased performance on auditory behavioral tests, small differences emerged, including delayed latencies for waves I, III, and V. Similarly, few significant group differences were observed for peak amplitudes and latencies of the speech-ABR when comparing at the whole group level

  2. Detection of auditory signals in quiet and noisy backgrounds while performing a visuo-spatial task

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    Vishakha W Rawool

    2016-01-01

    Full Text Available Context: The ability to detect important auditory signals while performing visual tasks may be further compounded by background chatter. Thus, it is important to know how task performance may interact with background chatter to hinder signal detection. Aim: To examine any interactive effects of speech spectrum noise and task performance on the ability to detect signals. Settings and Design: The setting was a sound-treated booth. A repeated measures design was used. Materials and Methods: Auditory thresholds of 20 normal adults were determined at 0.5, 1, 2 and 4 kHz in the following conditions presented in a random order: (1 quiet with attention; (2 quiet with a visuo-spatial task or puzzle (distraction; (3 noise with attention and (4 noise with task. Statistical Analysis: Multivariate analyses of variance (MANOVA with three repeated factors (quiet versus noise, visuo-spatial task versus no task, signal frequency. Results: MANOVA revealed significant main effects for noise and signal frequency and significant noise–frequency and task–frequency interactions. Distraction caused by performing the task worsened the thresholds for tones presented at the beginning of the experiment and had no effect on tones presented in the middle. At the end of the experiment, thresholds (4 kHz were better while performing the task than those obtained without performing the task. These effects were similar across the quiet and noise conditions. Conclusion: Detection of auditory signals is difficult at the beginning of a distracting visuo-spatial task but over time, task learning and auditory training effects can nullify the effect of distraction and may improve detection of high frequency sounds.

  3. Auditory and Cognitive Factors Associated with Speech-in-Noise Complaints following Mild Traumatic Brain Injury.

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    Hoover, Eric C; Souza, Pamela E; Gallun, Frederick J

    2017-04-01

    Auditory complaints following mild traumatic brain injury (MTBI) are common, but few studies have addressed the role of auditory temporal processing in speech recognition complaints. In this study, deficits understanding speech in a background of speech noise following MTBI were evaluated with the goal of comparing the relative contributions of auditory and nonauditory factors. A matched-groups design was used in which a group of listeners with a history of MTBI were compared to a group matched in age and pure-tone thresholds, as well as a control group of young listeners with normal hearing (YNH). Of the 33 listeners who participated in the study, 13 were included in the MTBI group (mean age = 46.7 yr), 11 in the Matched group (mean age = 49 yr), and 9 in the YNH group (mean age = 20.8 yr). Speech-in-noise deficits were evaluated using subjective measures as well as monaural word (Words-in-Noise test) and sentence (Quick Speech-in-Noise test) tasks, and a binaural spatial release task. Performance on these measures was compared to psychophysical tasks that evaluate monaural and binaural temporal fine-structure tasks and spectral resolution. Cognitive measures of attention, processing speed, and working memory were evaluated as possible causes of differences between MTBI and Matched groups that might contribute to speech-in-noise perception deficits. A high proportion of listeners in the MTBI group reported difficulty understanding speech in noise (84%) compared to the Matched group (9.1%), and listeners who reported difficulty were more likely to have abnormal results on objective measures of speech in noise. No significant group differences were found between the MTBI and Matched listeners on any of the measures reported, but the number of abnormal tests differed across groups. Regression analysis revealed that a combination of auditory and auditory processing factors contributed to monaural speech-in-noise scores, but the benefit of spatial separation was

  4. Motion words selectively modulate direction discrimination sensitivity for threshold motion

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    Pavan, Andrea; Skujevskis, Māris; Baggio, Giosuè

    2013-01-01

    Can speech selectively modulate the sensitivity of a sensory system so that, in the presence of a suitable linguistic context, the discrimination of certain perceptual features becomes more or less likely? In this study, participants heard upward or downward motion words followed by a single visual field of random dots moving upwards or downwards. The time interval between the onsets of the auditory and the visual stimuli was varied parametrically. Motion direction could be either discriminable (suprathreshold motion) or non-discriminable (threshold motion). Participants had to judge whether the dots were moving upward or downward. Results show a double dissociation between discrimination sensitivity (d′) and reaction times depending on whether vertical motion was above or at threshold. With suprathreshold motion, responses were faster for congruent directions of words and dots, but sensitivity was equal across conditions. With threshold motion, sensitivity was higher for congruent directions of words and dots, but responses were equally fast across conditions. The observed differences in sensitivity and response times were largest when the dots appeared 450 ms after word onset, that is, consistently with electrophysiology, at the time the up/down semantics of the word had become available. These data suggest that word meanings can alter the balance between signal and noise within the visual system and affect the perception of low-level sensory features. PMID:23596407

  5. Auditory Midbrain Implant: A Review

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    Lim, Hubert H.; Lenarz, Minoo; Lenarz, Thomas

    2009-01-01

    The auditory midbrain implant (AMI) is a new hearing prosthesis designed for stimulation of the inferior colliculus in deaf patients who cannot sufficiently benefit from cochlear implants. The authors have begun clinical trials in which five patients have been implanted with a single shank AMI array (20 electrodes). The goal of this review is to summarize the development and research that has led to the translation of the AMI from a concept into the first patients. This study presents the rationale and design concept for the AMI as well a summary of the animal safety and feasibility studies that were required for clinical approval. The authors also present the initial surgical, psychophysical, and speech results from the first three implanted patients. Overall, the results have been encouraging in terms of the safety and functionality of the implant. All patients obtain improvements in hearing capabilities on a daily basis. However, performance varies dramatically across patients depending on the implant location within the midbrain with the best performer still not able to achieve open set speech perception without lip-reading cues. Stimulation of the auditory midbrain provides a wide range of level, spectral, and temporal cues, all of which are important for speech understanding, but they do not appear to sufficiently fuse together to enable open set speech perception with the currently used stimulation strategies. Finally, several issues and hypotheses for why current patients obtain limited speech perception along with several feasible solutions for improving AMI implementation are presented. PMID:19762428

  6. A Brain System for Auditory Working Memory.

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    Kumar, Sukhbinder; Joseph, Sabine; Gander, Phillip E; Barascud, Nicolas; Halpern, Andrea R; Griffiths, Timothy D

    2016-04-20

    The brain basis for auditory working memory, the process of actively maintaining sounds in memory over short periods of time, is controversial. Using functional magnetic resonance imaging in human participants, we demonstrate that the maintenance of single tones in memory is associated with activation in auditory cortex. In addition, sustained activation was observed in hippocampus and inferior frontal gyrus. Multivoxel pattern analysis showed that patterns of activity in auditory cortex and left inferior frontal gyrus distinguished the tone that was maintained in memory. Functional connectivity during maintenance was demonstrated between auditory cortex and both the hippocampus and inferior frontal cortex. The data support a system for auditory working memory based on the maintenance of sound-specific representations in auditory cortex by projections from higher-order areas, including the hippocampus and frontal cortex. In this work, we demonstrate a system for maintaining sound in working memory based on activity in auditory cortex, hippocampus, and frontal cortex, and functional connectivity among them. Specifically, our work makes three advances from the previous work. First, we robustly demonstrate hippocampal involvement in all phases of auditory working memory (encoding, maintenance, and retrieval): the role of hippocampus in working memory is controversial. Second, using a pattern classification technique, we show that activity in the auditory cortex and inferior frontal gyrus is specific to the maintained tones in working memory. Third, we show long-range connectivity of auditory cortex to hippocampus and frontal cortex, which may be responsible for keeping such representations active during working memory maintenance. Copyright © 2016 Kumar et al.

  7. Comparative study between pure tone audiometry and auditory steady-state responses in normal hearing subjects.

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    Beck, Roberto Miquelino de Oliveira; Ramos, Bernardo Faria; Grasel, Signe Schuster; Ramos, Henrique Faria; Moraes, Maria Flávia Bonadia B de; Almeida, Edigar Rezende de; Bento, Ricardo Ferreira

    2014-01-01

    Auditory steady-state responses (ASSR) are an important tool to detect objectively frequency-specific hearing thresholds. Pure-tone audiometry is the gold-standard for hearing evaluation, although sometimes it may be inconclusive, especially in children and uncooperative adults. Compare pure tone thresholds (PT) with ASSR thresholds in normal hearing subjects. In this prospective cross-sectional study we included 26 adults (n = 52 ears) of both genders, without any hearing complaints or otologic diseases and normal puretone thresholds. All subjects had clinical history, otomicroscopy, audiometry and immitance measurements. This evaluation was followed by the ASSR test. The mean pure-tone and ASSR thresholds for each frequency were calculated. The mean difference between PTand ASSR thresholdswas 7,12 for 500 Hz, 7,6 for 1000 Hz, 8,27 for 2000 Hz and 9,71 dB for 4000 Hz. There were no difference between PT and ASSR means at either frequency. ASSR thresholds were comparable to pure-tone thresholds in normal hearing adults. Nevertheless it should not be used as the only method of hearing evaluation.

  8. Tactile thresholds in healthy subjects

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    Metka Moharić

    2014-10-01

    Full Text Available Background: The assessment of sensory thresholds provides a method of examining the function of peripheral nerve fibers and their central connections. Quantitative sensory testing is a variant of conventional sensory testing wherein the goal is the quantification of the level of stimulation needed to produce a particular sensation. While thermal and vibratory testing are established methods in assessment of sensory thresholds, assessment of tactile thresholds with monofilaments is not used routinely. The purpose of this study was to assess the tactile thresholds in normal healthy population.Methods: In 39 healthy volunteers (19 men aged 21 to 71 years, tactile thresholds were assessed with von Frey’s hair in 7 parts of the body bilaterally.Results: We found touch sensitivity not to be dependent on age or gender. The right side was significantly more sensitive in the lateral part of the leg (p=0.011 and the left side in the medial part of the arm (p=0.022. There were also significant differences between sites (p<0.001, whereby distal parts of the body were more sensitive.Conclusions: Von Frey filaments allow the estimation of tactile thresholds without the need for complicated instrumentation.

  9. Newborn hearing screening in prematurity: fate of screening failures and auditory maturation.

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    Yang, H C; Sung, C M; Shin, D J; Cho, Y B; Jang, C H; Cho, H-H

    2017-06-01

    The purpose of this study was to identify delayed auditory maturation and the fate of premature infants who failed the newborn hearing screening (NHS) in neonatal intensive care unit. A total of 1375 neonates underwent NHS using the transient evoked otoacoustic emission (TEOAE) in a tertiary hospital between 2007 and 2010 according to the Joint Committee on Infant Hearing guidelines. In addition, a structured telephone survey was given to caregivers of infants who were lost to follow-up NHS. Auditory steady-state response (ASSR) threshold and the threshold change in diagnostic test failures were analysed. Among the 1375 NICU babies, 344 (25.0%) babies, 111 (9.7%) babies and 64 (4.6%) babies failed to pass the first TEOAE, second TEOAE and diagnostic ASSR, respectively. However, at the age of about 5 years, 12 (0.9%) infants showed permanent hearing loss (PHL). The ASSR threshold improved from 69.0 ± 19.7 dB to 52.9 ± 21.6 dB in 67.5 dB for PHL was 9.00 (95% confidence interval, 1.7-46.7). Most of first TEOAE screening failures (91.3%) showed normal hearing and speech development. Hearing levels in premature infants can improve over time, particularly in neonates with initial ASSR threshold <67.5 dB. © 2016 John Wiley & Sons Ltd.

  10. Auditory agnosia due to long-term severe hydrocephalus caused by spina bifida - specific auditory pathway versus nonspecific auditory pathway.

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    Zhang, Qing; Kaga, Kimitaka; Hayashi, Akimasa

    2011-07-01

    A 27-year-old female showed auditory agnosia after long-term severe hydrocephalus due to congenital spina bifida. After years of hydrocephalus, she gradually suffered from hearing loss in her right ear at 19 years of age, followed by her left ear. During the time when she retained some ability to hear, she experienced severe difficulty in distinguishing verbal, environmental, and musical instrumental sounds. However, her auditory brainstem response and distortion product otoacoustic emissions were largely intact in the left ear. Her bilateral auditory cortices were preserved, as shown by neuroimaging, whereas her auditory radiations were severely damaged owing to progressive hydrocephalus. Although she had a complete bilateral hearing loss, she felt great pleasure when exposed to music. After years of self-training to read lips, she regained fluent ability to communicate. Clinical manifestations of this patient indicate that auditory agnosia can occur after long-term hydrocephalus due to spina bifida; the secondary auditory pathway may play a role in both auditory perception and hearing rehabilitation.

  11. Neural correlates of auditory recognition memory in the primate dorsal temporal pole.

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    Ng, Chi-Wing; Plakke, Bethany; Poremba, Amy

    2014-02-01

    Temporal pole (TP) cortex is associated with higher-order sensory perception and/or recognition memory, as human patients with damage in this region show impaired performance during some tasks requiring recognition memory (Olson et al. 2007). The underlying mechanisms of TP processing are largely based on examination of the visual nervous system in humans and monkeys, while little is known about neuronal activity patterns in the auditory portion of this region, dorsal TP (dTP; Poremba et al. 2003). The present study examines single-unit activity of dTP in rhesus monkeys performing a delayed matching-to-sample task utilizing auditory stimuli, wherein two sounds are determined to be the same or different. Neurons of dTP encode several task-relevant events during the delayed matching-to-sample task, and encoding of auditory cues in this region is associated with accurate recognition performance. Population activity in dTP shows a match suppression mechanism to identical, repeated sound stimuli similar to that observed in the visual object identification pathway located ventral to dTP (Desimone 1996; Nakamura and Kubota 1996). However, in contrast to sustained visual delay-related activity in nearby analogous regions, auditory delay-related activity in dTP is transient and limited. Neurons in dTP respond selectively to different sound stimuli and often change their sound response preferences between experimental contexts. Current findings suggest a significant role for dTP in auditory recognition memory similar in many respects to the visual nervous system, while delay memory firing patterns are not prominent, which may relate to monkeys' shorter forgetting thresholds for auditory vs. visual objects.

  12. Decreased auditory GABA+ concentrations in presbycusis demonstrated by edited magnetic resonance spectroscopy.

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    Gao, Fei; Wang, Guangbin; Ma, Wen; Ren, Fuxin; Li, Muwei; Dong, Yuling; Liu, Cheng; Liu, Bo; Bai, Xue; Zhao, Bin; Edden, Richard A E

    2015-02-01

    Gamma-aminobutyric acid (GABA) is the main inhibitory neurotransmitter in the central auditory system. Altered GABAergic neurotransmission has been found in both the inferior colliculus and the auditory cortex in animal models of presbycusis. Edited magnetic resonance spectroscopy (MRS), using the MEGA-PRESS sequence, is the most widely used technique for detecting GABA in the human brain. However, to date there has been a paucity of studies exploring changes to the GABA concentrations in the auditory region of patients with presbycusis. In this study, sixteen patients with presbycusis (5 males/11 females, mean age 63.1 ± 2.6 years) and twenty healthy controls (6 males/14 females, mean age 62.5 ± 2.3 years) underwent audiological and MRS examinations. Pure tone audiometry from 0.125 to 8 kHz and tympanometry were used to assess the hearing abilities of all subjects. The pure tone average (PTA; the average of hearing thresholds at 0.5, 1, 2 and 4 kHz) was calculated. The MEGA-PRESS sequence was used to measure GABA+ concentrations in 4 × 3 × 3 cm(3) volumes centered on the left and right Heschl's gyri. GABA+ concentrations were significantly lower in the presbycusis group compared to the control group (left auditory regions: p = 0.002, right auditory regions: p = 0.008). Significant negative correlations were observed between PTA and GABA+ concentrations in the presbycusis group (r = -0.57, p = 0.02), while a similar trend was found in the control group (r = -0.40, p = 0.08). These results are consistent with a hypothesis of dysfunctional GABAergic neurotransmission in the central auditory system in presbycusis and suggest a potential treatment target for presbycusis. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Electrophysiological assessment of auditory processing disorder in children with non-syndromic cleft lip and/or palate.

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    Ma, Xiaoran; McPherson, Bradley; Ma, Lian

    2016-01-01

    Cleft lip and/or palate is a common congenital craniofacial malformation found worldwide. A frequently associated disorder is conductive hearing loss, and this disorder has been thoroughly investigated in children with non-syndromic cleft lip and/or palate (NSCL/P). However, analysis of auditory processing function is rarely reported for this population, although this issue should not be ignored since abnormal auditory cortical structures have been found in populations with cleft disorders. The present study utilized electrophysiological tests to assess the auditory status of a large group of children with NSCL/P, and investigated whether this group had less robust central auditory processing abilities compared to craniofacially normal children. 146 children with NSCL/P who had normal peripheral hearing thresholds, and 60 craniofacially normal children aged from 6 to 15 years, were recruited. Electrophysiological tests, including auditory brainstem response (ABR), P1-N1-P2 complex, and P300 component recording, were conducted. ABR and N1 wave latencies were significantly prolonged in children with NSCL/P. An atypical developmental trend was found for long latency potentials in children with cleft compared to control group children. Children with unilateral cleft lip and palate showed a greater level of abnormal results compared with other cleft subgroups, whereas the cleft lip subgroup had the most robust responses for all tests. Children with NSCL/P may have slower than normal neural transmission times between the peripheral auditory nerve and brainstem. Possible delayed development of myelination and synaptogenesis may also influence auditory processing function in this population. Present research outcomes were consistent with previous, smaller sample size, electrophysiological studies on infants and children with cleft lip/palate disorders. In view of the these findings, and reports of educational disadvantage associated with cleft disorders, further research

  14. Electrophysiological assessment of auditory processing disorder in children with non-syndromic cleft lip and/or palate

    Directory of Open Access Journals (Sweden)

    Xiaoran Ma

    2016-08-01

    Full Text Available Objectives Cleft lip and/or palate is a common congenital craniofacial malformation found worldwide. A frequently associated disorder is conductive hearing loss, and this disorder has been thoroughly investigated in children with non-syndromic cleft lip and/or palate (NSCL/P. However, analysis of auditory processing function is rarely reported for this population, although this issue should not be ignored since abnormal auditory cortical structures have been found in populations with cleft disorders. The present study utilized electrophysiological tests to assess the auditory status of a large group of children with NSCL/P, and investigated whether this group had less robust central auditory processing abilities compared to craniofacially normal children. Methods 146 children with NSCL/P who had normal peripheral hearing thresholds, and 60 craniofacially normal children aged from 6 to 15 years, were recruited. Electrophysiological tests, including auditory brainstem response (ABR, P1-N1-P2 complex, and P300 component recording, were conducted. Results ABR and N1 wave latencies were significantly prolonged in children with NSCL/P. An atypical developmental trend was found for long latency potentials in children with cleft compared to control group children. Children with unilateral cleft lip and palate showed a greater level of abnormal results compared with other cleft subgroups, whereas the cleft lip subgroup had the most robust responses for all tests. Conclusion Children with NSCL/P may have slower than normal neural transmission times between the peripheral auditory nerve and brainstem. Possible delayed development of myelination and synaptogenesis may also influence auditory processing function in this population. Present research outcomes were consistent with previous, smaller sample size, electrophysiological studies on infants and children with cleft lip/palate disorders. In view of the these findings, and reports of educational

  15. Auditory assessment of patients with acute uncomplicated Plasmodium falciparum malaria treated with three-day mefloquine-artesunate on the north-western border of Thailand

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    Carrara, Verena I; Phyo, Aung P; Nwee, Paw; Soe, Ma; Htoo, Hsar; Arunkamomkiri, Jaruwan; Singhasivanon, Pratap; Nosten, François

    2008-01-01

    Background The use of artemisinin derivatives has increased exponentially with the deployment of artemisinin combination therapy (ACT) in all malarious areas. They are highly effective and are considered safe, but in animal studies artemisinin derivatives produce neurotoxicity targeting mainly the auditory and vestibular pathways. The debate remains as to whether artemisinin derivatives induce similar toxicity in humans. Methods This prospective study assessed the effects on auditory function of a standard 3-day oral dose of artesunate (4 mg/kg/day) combined with mefloquine (25 mg/kg) in patients with acute uncomplicated falciparum malaria treated at the Shoklo Malaria Research Unit, on the Thai-Burmese border. A complete auditory evaluation with tympanometry, audiometry and auditory brainstem responses (ABR) was performed before the first dose and seven days after initiation of the antimalarial treatment. Results Complete auditory tests at day 0 (D0) and day 7 (D7) were obtained for 93 patients. Hearing loss (threshold > 25 dB) on admission was common (57%) and associated with age only. No patient had a threshold change exceeding 10 dB between D0 and D7 at any tested frequency. No patient showed a shift in Wave III peak latency of more than 0.30 msec between baseline and D7. Conclusion Neither audiometric or the ABR tests showed clinical evidence of auditory toxicity seven days after receiving oral artesunate and mefloquine. PMID:18986553

  16. Comparison of distortion product otoacoustic emissions and pure tone audiometry in occupational screening for auditory deficit due to noise exposure.

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    Wooles, N; Mulheran, M; Bray, P; Brewster, M; Banerjee, A R

    2015-12-01

    To examine whether distortion product otoacoustic emissions can serve as a replacement for pure tone audiometry in longitudinal screening for occupational noise exposure related auditory deficit. A retrospective review was conducted of pure tone audiometry and distortion product otoacoustic emission data obtained sequentially during mandatory screening of brickyard workers (n = 16). Individual pure tone audiometry thresholds were compared with distortion product otoacoustic emission amplitudes, and a correlation of these measurements was conducted. Pure tone audiometry threshold elevation was identified in 13 out of 16 workers. When distortion product otoacoustic emission amplitudes were compared with pure tone audiometry thresholds at matched frequencies, no evidence of a robust relationship was apparent. Seven out of 16 workers had substantial distortion product otoacoustic emissions with elevated pure tone audiometry thresholds. No clinically relevant predictive relationship between distortion product otoacoustic emission amplitude and pure tone audiometry threshold was apparent. These results do not support the replacement of pure tone audiometry with distortion product otoacoustic emissions in screening. Distortion product otoacoustic emissions at frequencies associated with elevated pure tone audiometry thresholds are evidence of intact outer hair cell function, suggesting that sites distinct from these contribute to auditory deficit following ototrauma.

  17. Auditory memory function in expert chess players.

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    Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona

    2015-01-01

    Chess is a game that involves many aspects of high level cognition such as memory, attention, focus and problem solving. Long term practice of chess can improve cognition performances and behavioral skills. Auditory memory, as a kind of memory, can be influenced by strengthening processes following long term chess playing like other behavioral skills because of common processing pathways in the brain. The purpose of this study was to evaluate the auditory memory function of expert chess players using the Persian version of dichotic auditory-verbal memory test. The Persian version of dichotic auditory-verbal memory test was performed for 30 expert chess players aged 20-35 years and 30 non chess players who were matched by different conditions; the participants in both groups were randomly selected. The performance of the two groups was compared by independent samples t-test using SPSS version 21. The mean score of dichotic auditory-verbal memory test between the two groups, expert chess players and non-chess players, revealed a significant difference (p≤ 0.001). The difference between the ears scores for expert chess players (p= 0.023) and non-chess players (p= 0.013) was significant. Gender had no effect on the test results. Auditory memory function in expert chess players was significantly better compared to non-chess players. It seems that increased auditory memory function is related to strengthening cognitive performances due to playing chess for a long time.

  18. Looming auditory collision warnings for driving.

    Science.gov (United States)

    Gray, Rob

    2011-02-01

    A driving simulator was used to compare the effectiveness of increasing intensity (looming) auditory warning signals with other types of auditory warnings. Auditory warnings have been shown to speed driver reaction time in rear-end collision situations; however, it is not clear which type of signal is the most effective. Although verbal and symbolic (e.g., a car horn) warnings have faster response times than abstract warnings, they often lead to more response errors. Participants (N=20) experienced four nonlooming auditory warnings (constant intensity, pulsed, ramped, and car horn), three looming auditory warnings ("veridical," "early," and "late"), and a no-warning condition. In 80% of the trials, warnings were activated when a critical response was required, and in 20% of the trials, the warnings were false alarms. For the early (late) looming warnings, the rate of change of intensity signaled a time to collision (TTC) that was shorter (longer) than the actual TTC. Veridical looming and car horn warnings had significantly faster brake reaction times (BRT) compared with the other nonlooming warnings (by 80 to 160 ms). However, the number of braking responses in false alarm conditions was significantly greater for the car horn. BRT increased significantly and systematically as the TTC signaled by the looming warning was changed from early to veridical to late. Looming auditory warnings produce the best combination of response speed and accuracy. The results indicate that looming auditory warnings can be used to effectively warn a driver about an impending collision.

  19. Functional imaging of auditory scene analysis.

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    Gutschalk, Alexander; Dykstra, Andrew R

    2014-01-01

    Our auditory system is constantly faced with the task of decomposing the complex mixture of sound arriving at the ears into perceptually independent streams constituting accurate representations of individual sound sources. This decomposition, termed auditory scene analysis, is critical for both survival and communication, and is thought to underlie both speech and music perception. The neural underpinnings of auditory scene analysis have been studied utilizing invasive experiments with animal models as well as non-invasive (MEG, EEG, and fMRI) and invasive (intracranial EEG) studies conducted with human listeners. The present article reviews human neurophysiological research investigating the neural basis of auditory scene analysis, with emphasis on two classical paradigms termed streaming and informational masking. Other paradigms - such as the continuity illusion, mistuned harmonics, and multi-speaker environments - are briefly addressed thereafter. We conclude by discussing the emerging evidence for the role of auditory cortex in remapping incoming acoustic signals into a perceptual representation of auditory streams, which are then available for selective attention and further conscious processing. This article is part of a Special Issue entitled Human Auditory Neuroimaging. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. Recognition of plosive syllables in noise: comparison of an auditory model with human performance.

    Science.gov (United States)

    Ainsworth, W A; Meyer, G F

    1994-08-01

    Some of the effects of noise on the perception of plosive-vowel syllables have been investigated. It was found that noise added to the syllables for the duration of the speech had a more deleterious effect on perception than noise of the same intensity played continuously. Physiological experiments have shown that the response thresholds of cochlear nerve fibers to tones are raised by continuous background noise but not by short bursts of noise. It is suggested that this may be responsible for the speech perception results. In order to investigate this, an auditory model was developed which incorporated response threshold shifts. This was interfaced to a hidden Markov model recognizer and tested with the same sounds that were employed in the human perception experiments. The recognition scores were greater with the threshold shifts than without them.

  1. Auditory Connections and Functions of Prefrontal Cortex

    Directory of Open Access Journals (Sweden)

    Bethany ePlakke

    2014-07-01

    Full Text Available The functional auditory system extends from the ears to the frontal lobes with successively more complex functions occurring as one ascends the hierarchy of the nervous system. Several areas of the frontal lobe receive afferents from both early and late auditory processing regions within the temporal lobe. Afferents from the early part of the cortical auditory system, the auditory belt cortex, which are presumed to carry information regarding auditory features of sounds, project to only a few prefrontal regions and are most dense in the ventrolateral prefrontal cortex (VLPFC. In contrast, projections from the parabelt and the rostral superior temporal gyrus (STG most likely convey more complex information and target a larger, widespread region of the prefrontal cortex. Neuronal responses reflect these anatomical projections as some prefrontal neurons exhibit responses to features in acoustic stimuli, while other neurons display task-related responses. For example, recording studies in non-human primates indicate that VLPFC is responsive to complex sounds including vocalizations and that VLPFC neurons in area 12/47 respond to sounds with similar acoustic morphology. In contrast, neuronal responses during auditory working memory involve a wider region of the prefrontal cortex. In humans, the frontal lobe is involved in auditory detection, discrimination, and working memory. Past research suggests that dorsal and ventral subregions of the prefrontal cortex process different types of information with dorsal cortex processing spatial/visual information and ventral cortex processing non-spatial/auditory information. While this is apparent in the non-human primate and in some neuroimaging studies, most research in humans indicates that specific task conditions, stimuli or previous experience may bias the recruitment of specific prefrontal regions, suggesting a more flexible role for the frontal lobe during auditory cognition.

  2. Auditory connections and functions of prefrontal cortex

    Science.gov (United States)

    Plakke, Bethany; Romanski, Lizabeth M.

    2014-01-01

    The functional auditory system extends from the ears to the frontal lobes with successively more complex functions occurring as one ascends the hierarchy of the nervous system. Several areas of the frontal lobe receive afferents from both early and late auditory processing regions within the temporal lobe. Afferents from the early part of the cortical auditory system, the auditory belt cortex, which are presumed to carry information regarding auditory features of sounds, project to only a few prefrontal regions and are most dense in the ventrolateral prefrontal cortex (VLPFC). In contrast, projections from the parabelt and the rostral superior temporal gyrus (STG) most likely convey more complex information and target a larger, widespread region of the prefrontal cortex. Neuronal responses reflect these anatomical projections as some prefrontal neurons exhibit responses to features in acoustic stimuli, while other neurons display task-related responses. For example, recording studies in non-human primates indicate that VLPFC is responsive to complex sounds including vocalizations and that VLPFC neurons in area 12/47 respond to sounds with similar acoustic morphology. In contrast, neuronal responses during auditory working memory involve a wider region of the prefrontal cortex. In humans, the frontal lobe is involved in auditory detection, discrimination, and working memory. Past research suggests that dorsal and ventral subregions of the prefrontal cortex process different types of information with dorsal cortex processing spatial/visual information and ventral cortex processing non-spatial/auditory information. While this is apparent in the non-human primate and in some neuroimaging studies, most research in humans indicates that specific task conditions, stimuli or previous experience may bias the recruitment of specific prefrontal regions, suggesting a more flexible role for the frontal lobe during auditory cognition. PMID:25100931

  3. Cochlear, auditory brainstem responses in Type 1 diabetes: relationship with metabolic variables and diabetic complications.

    Science.gov (United States)

    Lasagni, A; Giordano, P; Lacilla, M; Raviolo, A; Trento, M; Camussi, E; Grassi, G; Charrier, L; Cavallo, F; Albera, R; Porta, M; Zanone, M M

    2016-09-01

    Few studies have analysed the presence of hearing abnormalities in diabetes. We assessed the presence of subclinical auditory alterations and their possible association with early vascular and neurological dysfunction in young adults with Type 1 diabetes of long duration. Thirty-one patients with Type 1 diabetes (mean age 33 ± 2.3 years, disease duration 25.7 ± 4.2 years) and 10 healthy controls underwent pure tone audiometry (PTA), distortion product otoacoustic emission (DPOAE) and auditory brainstem response (ABR) analyses. Associations with metabolic variables and chronic complications were explored. Compared with healthy controls, patients with diabetes had significantly higher mean hearing thresholds, although still within the normoacusic range. DPOAE intensities at medium frequencies (2.8-4 kHz) were significantly lower in patients with diabetes. In ABR, in addition to waves I, III and V, we observed the appearance of a visible wave IV in patients with diabetes compared with controls (prevalence 61% vs. 10%, P appearance was related to a prolonged I-V interval (4.40 ± 0.62 ms vs. 4.19 ± 0.58 ms, P trend towards an association between evidence of wave IV and the presence of somatic neuropathy or abnormal cardiovascular autonomic tests was observed. Young adults with long-term Type 1 diabetes have subclinical abnormalities in qualitative auditory perception, despite normal hearing thresholds, which might reflect neuropathic and/or vascular alterations. © 2015 Diabetes UK.

  4. Psychophysical Estimates of Frequency Discrimination: More than Just Limitations of Auditory Processing

    Directory of Open Access Journals (Sweden)

    Beate Sabisch

    2013-07-01

    Full Text Available Efficient auditory processing is hypothesized to support language and literacy development. However, behavioral tasks used to assess this hypothesis need to be robust to non-auditory specific individual differences. This study compared frequency discrimination abilities in a heterogeneous sample of adults using two different psychoacoustic task designs, referred to here as: 2I_6A_X and 3I_2AFC designs. The role of individual differences in nonverbal IQ (NVIQ, socioeconomic status (SES and musical experience in predicting frequency discrimination thresholds on each task were assessed using multiple regression analyses. The 2I_6A_X task was more cognitively demanding and hence more susceptible to differences specifically in SES and musical training. Performance on this task did not, however, relate to nonword repetition ability (a measure of language learning capacity. The 3I_2AFC task, by contrast, was only susceptible to musical training. Moreover, thresholds measured using it predicted some variance in nonword repetition performance. This design thus seems suitable for use in studies addressing questions regarding the role of auditory processing in supporting language and literacy development.

  5. Asymmetric excitatory synaptic dynamics underlie interaural time difference processing in the auditory system.

    Directory of Open Access Journals (Sweden)

    Pablo E Jercog

    2010-06-01

    Full Text Available Low-frequency sound localization depends on the neural computation of interaural time differences (ITD and relies on neurons in the auditory brain stem that integrate synaptic inputs delivered by the ipsi- and contralateral auditory pathways that start at the two ears. The first auditory neurons that respond selectively to ITD are found in the medial superior olivary nucleus (MSO. We identified a new mechanism for ITD coding using a brain slice preparation that preserves the binaural inputs to the MSO. There was an internal latency difference for the two excitatory pathways that would, if left uncompensated, position the ITD response function too far outside the physiological range to be useful for estimating ITD. We demonstrate, and support using a biophysically based computational model, that a bilateral asymmetry in excitatory post-synaptic potential (EPSP slopes provides a robust compensatory delay mechanism due to differential activation of low threshold potassium conductance on these inputs and permits MSO neurons to encode physiological ITDs. We suggest, more generally, that the dependence of spike probability on rate of depolarization, as in these auditory neurons, provides a mechanism for temporal order discrimination between EPSPs.

  6. Noise-induced hearing loss alters the temporal dynamics of auditory-nerve responses.

    Science.gov (United States)

    Scheidt, Ryan E; Kale, Sushrut; Heinz, Michael G

    2010-10-01

    Auditory-nerve fibers demonstrate dynamic response properties in that they adapt to rapid changes in sound level, both at the onset and offset of a sound. These dynamic response properties affect temporal coding of stimulus modulations that are perceptually relevant for many sounds such as speech and music. Temporal dynamics have been well characterized in auditory-nerve fibers from normal-hearing animals, but little is known about the effects of sensorineural hearing loss on these dynamics. This study examined the effects of noise-induced hearing loss on the temporal dynamics in auditory-nerve fiber responses from anesthetized chinchillas. Post-stimulus-time histograms were computed from responses to 50-ms tones presented at characteristic frequency and 30 dB above fiber threshold. Several response metrics related to temporal dynamics were computed from post-stimulus-time histograms and were compared between normal-hearing and noise-exposed animals. Results indicate that noise-exposed auditory-nerve fibers show significantly reduced response latency, increased onset response and percent adaptation, faster adaptation after onset, and slower recovery after offset. The decrease in response latency only occurred in noise-exposed fibers with significantly reduced frequency selectivity. These changes in temporal dynamics have important implications for temporal envelope coding in hearing-impaired ears, as well as for the design of dynamic compression algorithms for hearing aids.

  7. Auditory Outcomes with Hearing Rehabilitation in Children with Unilateral Hearing Loss: A Systematic Review.

    Science.gov (United States)

    Appachi, Swathi; Specht, Jessica L; Raol, Nikhila; Lieu, Judith E C; Cohen, Michael S; Dedhia, Kavita; Anne, Samantha

    2017-10-01

    Objective Options for management of unilateral hearing loss (UHL) in children include conventional hearing aids, bone-conduction hearing devices, contralateral routing of signal (CROS) aids, and frequency-modulating (FM) systems. The objective of this study was to systematically review the current literature to characterize auditory outcomes of hearing rehabilitation options in UHL. Data Sources PubMed, EMBASE, Medline, CINAHL, and Cochrane Library were searched from inception to January 2016. Manual searches of bibliographies were also performed. Review Methods Studies analyzing auditory outcomes of hearing amplification in children with UHL were included. Outcome measures included functional and objective auditory results. Two independent reviewers evaluated each abstract and article. Results Of the 249 articles identified, 12 met inclusion criteria. Seven articles solely focused on outcomes with bone-conduction hearing devices. Outcomes favored improved pure-tone averages, speech recognition thresholds, and sound localization in implanted patients. Five studies focused on FM systems, conventional hearing aids, or CROS hearing aids. Limited data are available but suggest a trend toward improvement in speech perception with hearing aids. FM systems were shown to have the most benefit for speech recognition in noise. Studies evaluating CROS hearing aids demonstrated variable outcomes. Conclusions Data evaluating functional and objective auditory measures following hearing amplification in children with UHL are limited. Most studies do suggest improvement in speech perception, speech recognition in noise, and sound localization with a hearing rehabilitation device.

  8. Auditory findings and electrophysiologics in individuals with G/BBB syndrome.

    Science.gov (United States)

    Cassab, Tatiana Vialôgo; Zanchetta, Sthella; Giacheti, Célia Maria; Zorzetto, Neivo Luiz; Richieri-Costa, Antonio

    2011-01-01

    The G/BBB syndrome is a rare condition characterized by hypertelorism, cleft lip and palate, and hypospadias. No studies were found on the hearing of individuals with this syndrome. To investigate the auditory function in patients with G/BBB syndrome, such as the occurrence of hearing loss, and central and peripheral auditory nerve conduction. Fourteen male patients aged 7-34 years with the G/BBB syndrome were assessed by otoscopy, audiometry, tympanometry and evoked auditory brainstem response (ABR). A retrospective clinical series study. Audiometric thresholds were normal in 12 (66.7%) of the sample and altered in two (33.3%), one with conductive and one with sensorineural loss. ABR results were: all patients had normal absolute wave I latencies; absolute wave III and V latencies were increased in two and six patients, respectively; interpeak latencies I-III, IV and V interpeak latencies were increased in four, three and eight patients respectively. Hearing loss can occur in the G/BBB syndrome. There is evidence of central auditory pathway involvement in the brainstem. Imaging studies are needed to clarify the clinical findings.

  9. Neuromechanistic Model of Auditory Bistability.

    Directory of Open Access Journals (Sweden)

    James Rankin

    2015-11-01

    Full Text Available Sequences of higher frequency A and lower frequency B tones repeating in an ABA- triplet pattern are widely used to study auditory streaming. One may experience either an integrated percept, a single ABA-ABA- stream, or a segregated percept, separate but simultaneous streams A-A-A-A- and -B---B--. During minutes-long presentations, subjects may report irregular alternations between these interpretations. We combine neuromechanistic modeling and psychoacoustic experiments to study these persistent alternations and to characterize the effects of manipulating stimulus parameters. Unlike many phenomenological models with abstract, percept-specific competition and fixed inputs, our network model comprises neuronal units with sensory feature dependent inputs that mimic the pulsatile-like A1 responses to tones in the ABA- triplets. It embodies a neuronal computation for percept competition thought to occur beyond primary auditory cortex (A1. Mutual inhibition, adaptation and noise are implemented. We include slow NDMA recurrent excitation for local temporal memory that enables linkage across sound gaps from one triplet to the next. Percepts in our model are identified in the firing patterns of the neuronal units. We predict with the model that manipulations of the frequency difference between tones A and B should affect the dominance durations of the stronger percept, the one dominant a larger fraction of time, more than those of the weaker percept-a property that has been previously established and generalized across several visual bistable paradigms. We confirm the qualitative prediction with our psychoacoustic experiments and use the behavioral data to further constrain and improve the model, achieving quantitative agreement between experimental and modeling results. Our work and model provide a platform that can be extended to consider other stimulus conditions, including the effects of context and volition.

  10. Assessing the aging effect on auditory-verbal memory by Persian version of dichotic auditory verbal memory test

    Directory of Open Access Journals (Sweden)

    Zahra Shahidipour

    2014-01-01

    Conclusion: Based on the obtained results, significant reduction in auditory memory was seen in aged group and the Persian version of dichotic auditory-verbal memory test, like many other auditory verbal memory tests, showed the aging effects on auditory verbal memory performance.

  11. On amplitude zeros at threshold

    CERN Document Server

    Argyres, E N; Kleiss, R H

    1993-01-01

    The occurrence of zeros of 2 to n amplitudes at threshold in scalar theories is studied. We find a differential equation for the scalar potential, which incorporates all known cases where the 2 to n amplitudes at threshold vanish for all sufficiently large $n$, in all space-time dimensions, $d\\ge 1$. This equation is related to the reflectionless potentials of Quantum Mechanics and to integrable theories in 1+1 dimensions. As an application, we find that the sine-Gordon potential and its hyperbolic version, the sinh-Gordon potential, also have amplitude zeros at threshold, ${\\cal A}(2\\to n)=0$, for $n\\ge 4$ and $d\\ge 2$, independently of the mass and the coupling constant.

  12. Threshold concepts in dental education.

    Science.gov (United States)

    Kinchin, I M; Cabot, L B; Kobus, M; Woolford, M

    2011-11-01

    The paper presents a conceptual framework to inform dental education. Drawing from a vast body of research into student learning, the simple model presented here has an explanatory value in describing what is currently observed to happen and a predictive value in guiding future teaching practices. We introduce to dental education the application of threshold concepts that have a transformative role in offering a new vision of the curriculum that helps to move away from the medieval transmission model of higher education towards a dual processing model that better reflects the way in which professionals operate within the discipline. Threshold concepts give a role for the student voice in offering a novice perspective which is paradoxically something that is out of reach of the subject expert. Finally, the application of threshold concepts highlights some of the weaknesses in the competency-based training model of clinical teaching. 2011 John Wiley & Sons A/S.

  13. Auditory rehabilitation after stroke: treatment of auditory processing disorders in stroke patients with personal frequency-modulated (FM) systems.

    Science.gov (United States)

    Koohi, Nehzat; Vickers, Deborah; Chandrashekar, Hoskote; Tsang, Benjamin; Werring, David; Bamiou, Doris-Eva

    2017-03-01

    Auditory disability due to impaired auditory processing (AP) despite normal pure-tone thresholds is common after stroke, and it leads to isolation, reduced quality of life and physical decline. There are currently no proven remedial interventions for AP deficits in stroke patients. This is the first study to investigate the benefits of personal frequency-modulated (FM) systems in stroke patients with disordered AP. Fifty stroke patients had baseline audiological assessments, AP tests and completed the (modified) Amsterdam Inventory for Auditory Disability and Hearing Handicap Inventory for Elderly questionnaires. Nine out of these 50 patients were diagnosed with disordered AP based on severe deficits in understanding speech in background noise but with normal pure-tone thresholds. These nine patients underwent spatial speech-in-noise testing in a sound-attenuating chamber (the "crescent of sound") with and without FM systems. The signal-to-noise ratio (SNR) for 50% correct speech recognition performance was measured with speech presented from 0° azimuth and competing babble from ±90° azimuth. Spatial release from masking (SRM) was defined as the difference between SNRs measured with co-located speech and babble and SNRs measured with spatially separated speech and babble. The SRM significantly improved when babble was spatially separated from target speech, while the patients had the FM systems in their ears compared to without the FM systems. Personal FM systems may substantially improve speech-in-noise deficits in stroke patients who are not eligible for conventional hearing aids. FMs are feasible in stroke patients and show promise to address impaired AP after stroke. Implications for Rehabilitation This is the first study to investigate the benefits of personal frequency-modulated (FM) systems in stroke patients with disordered AP. All cases significantly improved speech perception in noise with the FM systems, when noise was spatially separated from the

  14. Effects of an Auditory Lateralization Training in Children Suspected to Central Auditory Processing Disorder

    OpenAIRE

    Lotfi, Yones; Moosavi, Abdollah; Abdollahi, Farzaneh Zamiri; BAKHSHI, Enayatollah; Sadjedi, Hamed

    2016-01-01

    Background and Objectives Central auditory processing disorder [(C)APD] refers to a deficit in auditory stimuli processing in nervous system that is not due to higher-order language or cognitive factors. One of the problems in children with (C)APD is spatial difficulties which have been overlooked despite their significance. Localization is an auditory ability to detect sound sources in space and can help to differentiate between the desired speech from other simultaneous sound sources. Aim o...

  15. Use of auditory learning to manage listening problems in children

    OpenAIRE

    Moore, David R.; Halliday, Lorna F.; Amitay, Sygal

    2008-01-01

    This paper reviews recent studies that have used adaptive auditory training to address communication problems experienced by some children in their everyday life. It considers the auditory contribution to developmental listening and language problems and the underlying principles of auditory learning that may drive further refinement of auditory learning applications. Following strong claims that language and listening skills in children could be improved by auditory learning, researchers hav...

  16. AUDITORY REACTION TIME IN BASKETBALL PLAYERS AND HEALTHY CONTROLS

    OpenAIRE

    Ghuntla Tejas P.; Mehta Hemant B.; Gokhale Pradnya A.; Shah Chinmay J.

    2013-01-01

    Reaction is purposeful voluntary response to different stimuli as visual or auditory stimuli. Auditory reaction time is time required to response to auditory stimuli. Quickness of response is very important in games like basketball. This study was conducted to compare auditory reaction time of basketball players and healthy controls. The auditory reaction time was measured by the reaction time instrument in healthy controls and basketball players. Simple reaction time and choice reaction time...

  17. Baryon Form Factors at Threshold

    Energy Technology Data Exchange (ETDEWEB)

    Baldini Ferroli, Rinaldo [Museo Storico della Fisica e Centro Studi e Ricerche ' E. Fermi' , Rome (Italy); INFN, Laboratori Nazionali di Frascati, Frascati (Italy); Pacetti, Simone [INFN and Dipartimento di Fisica, Universita di Perugia, Perugia (Italy)

    2012-04-15

    An extensive study of the e{sup +}e{sup -}{yields}pp{sup Macron }BABAR cross section data is presented. Two unexpected outcomes have been found: the modulus of the proton form factor is normalized to one at threshold, i.e.: |G{sup p}(4M{sub p}{sup 2})|=1, as a pointlike fermion, and the resummation factor in the Sommerfeld formula is not needed. Other e{sup +}e{sup -} {yields} baryon-antibaryon cross sections show a similar behavior near threshold.

  18. On computational Gestalt detection thresholds.

    Science.gov (United States)

    Grompone von Gioi, Rafael; Jakubowicz, Jérémie

    2009-01-01

    The aim of this paper is to show some recent developments of computational Gestalt theory, as pioneered by Desolneux, Moisan and Morel. The new results allow to predict much more accurately the detection thresholds. This step is unavoidable if one wants to analyze visual detection thresholds in the light of computational Gestalt theory. The paper first recalls the main elements of computational Gestalt theory. It points out a precision issue in this theory, essentially due to the use of discrete probability distributions. It then proposes to overcome this issue by using continuous probability distributions and illustrates it on the meaningful alignment detector of Desolneux et al.

  19. [Assessment of the efficiency of the auditory training in children with dyslalia and auditory processing disorders].

    Science.gov (United States)

    Włodarczyk, Elżbieta; Szkiełkowska, Agata; Skarżyński, Henryk; Piłka, Adam

    2011-01-01

    To assess effectiveness of the auditory training in children with dyslalia and central auditory processing disorders. Material consisted of 50 children aged 7-9-years-old. Children with articulation disorders stayed under long-term speech therapy care in the Auditory and Phoniatrics Clinic. All children were examined by a laryngologist and a phoniatrician. Assessment included tonal and impedance audiometry and speech therapists' and psychologist's consultations. Additionally, a set of electrophysiological examinations was performed - registration of N2, P2, N2, P2, P300 waves and psychoacoustic test of central auditory functions: FPT - frequency pattern test. Next children took part in the regular auditory training and attended speech therapy. Speech assessment followed treatment and therapy, again psychoacoustic tests were performed and P300 cortical potentials were recorded. After that statistical analyses were performed. Analyses revealed that application of auditory training in patients with dyslalia and other central auditory disorders is very efficient. Auditory training may be a very efficient therapy supporting speech therapy in children suffering from dyslalia coexisting with articulation and central auditory disorders and in children with educational problems of audiogenic origin. Copyright © 2011 Polish Otolaryngology Society. Published by Elsevier Urban & Partner (Poland). All rights reserved.

  20. Evaluation of an auditory assessment protocol for Chinese infants with nonsyndromic cleft lip and/or palate.

    Science.gov (United States)

    Yang, Frank F; McPherson, Bradley; Shu, Huang

    2012-09-01

    To objectively investigate the auditory status of mainland Chinese infants with nonsyndromic cleft lip and/or palate and to evaluate an auditory assessment protocol for this group. Prospective cohort case review. A total of 42 Chinese infants with nonsyndromic cleft lip and/or palate aged 6 to 24 months. The hearing profiles of participants were acquired using otoscopy, tympanometry, transient-evoked otoacoustic emissions, and auditory brainstem response estimated hearing threshold. The efficiency of the current audiological test battery was analyzed also. Sixty-four (64.2) percent of infants with nonsyndromic cleft lip and/or palate (55.9% of ears) were suspected to have middle ear disorder, and 85.7% of all subjects (83.3% of ears) were found to have hearing loss. Of those with confirmed loss, the overall mean auditory brainstem response estimated air-conduction hearing threshold was 53.5 ± 13.6 decibel normal hearing level [db nHL]. Using auditory brainstem response thresholds as a reference standard, the diagnostic agreement with the other assessment tools for normal/abnormal results was otoscopy, 69% (κ  =  .57); tympanometry, 66.7% (κ  =  .53); and transient-evoked otoacoustic emissions, 80% (κ  =  .64). The high prevalence of middle ear disease and hearing loss in mainland Chinese infants with nonsyndromic cleft lip and/or palate in this study was in contrast to previous studies of older age groups of Chinese children conducted in Hong Kong and Singapore. The audiological assessment protocol used in our study could provide useful information; although, modifications may be necessary to ensure a complete diagnostic overview for children with craniofacial clefts.

  1. The neural substrate for binaural masking level differences in the auditory cortex.

    Science.gov (United States)

    Gilbert, Heather J; Shackleton, Trevor M; Krumbholz, Katrin; Palmer, Alan R

    2015-01-07

    The binaural masking level difference (BMLD) is a phenomenon whereby a signal that is identical at each ear (S0), masked by a noise that is identical at each ear (N0), can be made 12-15 dB more detectable by inverting the waveform of either the tone or noise at one ear (Sπ, Nπ). Single-cell responses to BMLD stimuli were measured in the primary auditory cortex of urethane-anesthetized guinea pigs. Firing rate was measured as a function of signal level of a 500 Hz pure tone masked by low-passed white noise. Responses were similar to those reported in the inferior colliculus. At low signal levels, the response was dominated by the masker. At higher signal levels, firing rate either increased or decreased. Detection thresholds for each neuron were determined using signal detection theory. Few neurons yielded measurable detection thresholds for all stimulus conditions, with a wide range in thresholds. However, across the entire population, the lowest thresholds were consistent with human psychophysical BMLDs. As in the inferior colliculus, the shape of the firing-rate versus signal-level functions depended on the neurons' selectivity for interaural time difference. Our results suggest that, in cortex, BMLD signals are detected from increases or decreases in the firing rate, consistent with predictions of cross-correlation models of binaural processing and that the psychophysical detection threshold is based on the lowest neural thresholds across the population. Copyright © 2015 Gilbert et al.

  2. Great cormorants ( Phalacrocorax carbo) can detect auditory cues while diving

    Science.gov (United States)

    Hansen, Kirstin Anderson; Maxwell, Alyssa; Siebert, Ursula; Larsen, Ole Næsbye; Wahlberg, Magnus

    2017-06-01

    In-air hearing in birds has been thoroughly investigated. Sound provides birds with auditory information for species and individual recognition from their complex vocalizations, as well as cues while foraging and for avoiding predators. Some 10% of existing species of birds obtain their food under the water surface. Whether some of these birds make use of acoustic cues while underwater is unknown. An interesting species in this respect is the great cormorant ( Phalacrocorax carbo), being one of the most effective marine predators and relying on the aquatic environment for food year round. Here, its underwater hearing abilities were investigated using psychophysics, where the bird learned to detect the presence or absence of a tone while submerged. The greatest sensitivity was found at 2 kHz, with an underwater hearing threshold of 71 dB re 1 μPa rms. The great cormorant is better at hearing underwater than expected, and the hearing thresholds are comparable to seals and toothed whales in the frequency band 1-4 kHz. This opens up the possibility of cormorants and other aquatic birds having special adaptations for underwater hearing and making use of underwater acoustic cues from, e.g., conspecifics, their surroundings, as well as prey and predators.

  3. Auditory motion capturing ambiguous visual motion

    Directory of Open Access Journals (Sweden)

    Arjen eAlink

    2012-01-01

    Full Text Available In this study, it is demonstrated that moving sounds have an effect on the direction in which one sees visual stimuli move. During the main experiment sounds were presented consecutively at four speaker locations inducing left- or rightwards auditory apparent motion. On the path of auditory apparent motion, visual apparent motion stimuli were presented with a high degree of directional ambiguity. The main outcome of this experiment is that our participants perceived visual apparent motion stimuli that were ambiguous (equally likely to be perceived as moving left- or rightwards more often as moving in the same direction than in the opposite direction of auditory apparent motion. During the control experiment we replicated this finding and found no effect of sound motion direction on eye movements. This indicates that auditory motion can capture our visual motion percept when visual motion direction is insufficiently determinate without affecting eye movements.

  4. Reconstructing speech from human auditory cortex.

    Directory of Open Access Journals (Sweden)

    Brian N Pasley

    2012-01-01

    Full Text Available How the human auditory system extracts perceptually relevant acoustic features of speech is unknown. To address this question, we used intracranial recordings from nonprimary auditory cortex in the human superior temporal gyrus to determine what acoustic information in speech sounds can be reconstructed from population neural activity. We found that slow and intermediate temporal fluctuations, such as those corresponding to syllable rate, were accurately reconstructed using a linear model based on the auditory spectrogram. However, reconstruction of fast temporal fluctuations, such as syllable onsets and offsets, required a nonlinear sound representation based on temporal modulation energy. Reconstruction accuracy was highest within the range of spectro-temporal fluctuations that have been found to be critical for speech intelligibility. The decoded speech representations allowed readout and identification of individual words directly from brain activity during single trial sound presentations. These findings reveal neural encoding mechanisms of speech acoustic parameters in higher order human auditory cortex.

  5. Auditory Neuropathy Spectrum Disorder (ANSD) (For Parents)

    Science.gov (United States)

    ... to the inner row of hair cells or synapses between the inner hair cells and the auditory ... any other nerve-related problems. Ongoing speech and language testing . A child with ANSD needs regular visits ...

  6. Auditory Feedback and the Online Shopping Experience

    National Research Council Canada - National Science Library

    Ryann Reynolds-McIlnay

    2014-01-01

      The present research proposes that the presence of auditory feedback increases satisfaction with the shopping experience, confidence in the retailer, and the likelihood to return to the retailer...

  7. Environment for Auditory Research Facility (EAR)

    Data.gov (United States)

    Federal Laboratory Consortium — EAR is an auditory perception and communication research center enabling state-of-the-art simulation of various indoor and outdoor acoustic environments. The heart...

  8. Childhood trauma and auditory verbal hallucinations

    NARCIS (Netherlands)

    Daalman, K.; Diederen, K. M. J.; Derks, E. M.; van Lutterveld, R.; Kahn, R. S.; Sommer, Iris E. C.

    2012-01-01

    Background. Hallucinations have consistently been associated with traumatic experiences during childhood. This association appears strongest between physical and sexual abuse and auditory verbal hallucinations (AVH). It remains unclear whether traumatic experiences mainly colour the content of AVH

  9. Auditory stimulation and cardiac autonomic regulation

    Directory of Open Access Journals (Sweden)

    Vitor E. Valenti

    2012-08-01

    Full Text Available Previous studies have already demonstrated that auditory stimulation with music influences the cardiovascular system. In this study, we described the relationship between musical auditory stimulation and heart rate variability. Searches were performed with the Medline, SciELO, Lilacs and Cochrane databases using the following keywords: "auditory stimulation", "autonomic nervous system", "music" and "heart rate variability". The selected studies indicated that there is a strong correlation between noise intensity and vagal-sympathetic balance. Additionally, it was reported that music therapy improved heart rate variability in anthracycline-treated breast cancer patients. It was hypothesized that dopamine release in the striatal system induced by pleasurable songs is involved in cardiac autonomic regulation. Musical auditory stimulation influences heart rate variability through a neural mechanism that is not well understood. Further studies are necessary to develop new therapies to treat cardiovascular disorders.

  10. Effect of omega-3 on auditory system

    Directory of Open Access Journals (Sweden)

    Vida Rahimi

    2014-01-01

    Full Text Available Background and Aim: Omega-3 fatty acid have structural and biological roles in the body 's various systems . Numerous studies have tried to research about it. Auditory system is affected a s well. The aim of this article was to review the researches about the effect of omega-3 on auditory system.Methods: We searched Medline , Google Scholar, PubMed, Cochrane Library and SID search engines with the "auditory" and "omega-3" keywords and read textbooks about this subject between 19 70 and 20 13.Conclusion: Both excess and deficient amounts of dietary omega-3 fatty acid can cause harmful effects on fetal and infant growth and development of brain and central nervous system esspesially auditory system. It is important to determine the adequate dosage of omega-3.

  11. Auditory memory function in expert chess players

    OpenAIRE

    Fattahi, Fariba; Geshani, Ahmad; Jafari, Zahra; Jalaie, Shohreh; Salman Mahini, Mona

    2015-01-01

    Background: Chess is a game that involves many aspects of high level cognition such as memory, attention, focus and problem solving. Long term practice of chess can improve cognition performances and behavioral skills. Auditory memory, as a kind of memory, can be influenced by strengthening processes following long term chess playing like other behavioral skills because of common processing pathways in the brain. The purpose of this study was to evaluate the auditory memory function of expert...

  12. Mental concerts: musical imagery and auditory cortex.

    Science.gov (United States)

    Zatorre, Robert J; Halpern, Andrea R

    2005-07-07

    Most people intuitively understand what it means to "hear a tune in your head." Converging evidence now indicates that auditory cortical areas can be recruited even in the absence of sound and that this corresponds to the phenomenological experience of imagining music. We discuss these findings as well as some methodological challenges. We also consider the role of core versus belt areas in musical imagery, the relation between auditory and motor systems during imagery of music performance, and practical implications of this research.

  13. [Auditory performance analyses of cochlear implanted patients].

    Science.gov (United States)

    Ozdemir, Süleyman; Kıroğlu, Mete; Tuncer, Ulkü; Sahin, Rasim; Tarkan, Ozgür; Sürmelioğlu, Ozgür

    2011-01-01

    The aim of this study was to analyze the auditory performance development of cochlear implanted patients. The effects of age at implantation, gender, implanted ear and model of the cochlear implant on the patients' auditory performance were investigated. Twenty-eight patients (12 boys, 16 girls) with congenital prelingual hearing loss who underwent cochlear implant surgery at our clinic and a follow-up of at least 18 months were selected for the study. Listening Progress Profile (LiP), Monosyllable-Trochee-Polysyllable (MTP) and Meaningful Auditory Integration Scale (MAIS) tests were performed to analyze the auditory performances of the patients. To determine the effect of the age at implantation on the auditory performance, patients were assigned into two groups: group 1 (implantation age = or <60 months, mean 44.8 months) and group 2 (implantation age = or <60 months, mean 100.6 months). Group 2 had higher preoperative test scores than group 1 but after cochlear implant use, the auditory performance levels of the patients in group 1 improved faster and equalized to those of the patients in group 2 after 12-18 months. Our data showed that variables such as sex, implanted ear or model of the cochlear implant did not have any statistically significant effect on the auditory performance of the patients after cochlear implantation. We found a negative correlation between the implantation age and the auditory performance improvement in our study. We observed that children implanted at young age had a quicker language development and have had more success in reading, writing and other educational skills in the future.

  14. Thresholds

    DEFF Research Database (Denmark)

    Hansen, Peter Mandal

    2009-01-01

    Studies of transition spaces in arabic architecture from the architectural workshop Imagination, Damascus, Syria, august 2008 and with the participation of students from Syria, Germany and Denmark.......Studies of transition spaces in arabic architecture from the architectural workshop Imagination, Damascus, Syria, august 2008 and with the participation of students from Syria, Germany and Denmark....

  15. Crossing Thresholds in Academic Reading

    Science.gov (United States)

    Abbott, Rob

    2013-01-01

    This paper looks at the conceptual thresholds in relation to academic reading which might be crossed by undergraduate English Literature students. It is part of a wider study following 16 students through three years of undergraduate study. It uses theoretical ideas from Bakhtin and Foucault to analyse interviews with English lecturers. It…

  16. The Nature of Psychological Thresholds

    NARCIS (Netherlands)

    Rouder, Jeffrey N.; Morey, Richard D.

    Following G. T. Fechner (1966), thresholds have been conceptualized as the amount of intensity needed to transition between mental states, such as between a states of unconsciousness and consciousness. With the advent of the theory of signal detection, however, discrete-state theory and the

  17. Threshold enhancement of diphoton resonances

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    Aoife Bharucha

    2016-10-01

    Full Text Available We revisit a mechanism to enhance the decay width of (pseudo-scalar resonances to photon pairs when the process is mediated by loops of charged fermions produced near threshold. Motivated by the recent LHC data, indicating the presence of an excess in the diphoton spectrum at approximately 750 GeV, we illustrate this threshold enhancement mechanism in the case of a 750 GeV pseudoscalar boson A with a two-photon decay mediated by a charged and uncolored fermion having a mass at the 12MA threshold and a small decay width, <1 MeV. The implications of such a threshold enhancement are discussed in two explicit scenarios: i the Minimal Supersymmetric Standard Model in which the A state is produced via the top quark mediated gluon fusion process and decays into photons predominantly through loops of charginos with masses close to 12MA and ii a two Higgs doublet model in which A is again produced by gluon fusion but decays into photons through loops of vector-like charged heavy leptons. In both these scenarios, while the mass of the charged fermion has to be adjusted to be extremely close to half of the A resonance mass, the small total widths are naturally obtained if only suppressed three-body decay channels occur. Finally, the implications of some of these scenarios for dark matter are discussed.

  18. Threshold Concepts and Pedagogic Representation

    Science.gov (United States)

    Meyer, Jan H. F.

    2016-01-01

    Purpose: The purpose of this paper is to present a brief exposure to the development of the threshold concepts framework (TCF), the intention being to illuminate for interested readers a broader landscape of research activity than that perhaps conveyed by the individual contributions to this special edition. Design/Methodology/Approach: There is…

  19. Glial cell contributions to auditory brainstem development

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    Karina S Cramer

    2016-10-01

    Full Text Available Glial cells, previously thought to have generally supporting roles in the central nervous system, are emerging as essential contributors to multiple aspects of neuronal circuit function and development. This review focuses on the contributions of glial cells to the development of specialized auditory pathways in the brainstem. These pathways display specialized synapses and an unusually high degree of precision in circuitry that enables sound source localization. The development of these pathways thus requires highly coordinated molecular and cellular mechanisms. Several classes of glial cells, including astrocytes, oligodendrocytes, and microglia, have now been explored in these circuits in both avian and mammalian brainstems. Distinct populations of astrocytes are found over the course of auditory brainstem maturation. Early appearing astrocytes are associated with spatial compartments in the avian auditory brainstem. Factors from late appearing astrocytes promote synaptogenesis and dendritic maturation, and astrocytes remain integral parts of specialized auditory synapses. Oligodendrocytes play a unique role in both birds and mammals in highly regulated myelination essential for proper timing to decipher interaural cues. Microglia arise early in brainstem development and may contribute to maturation of auditory pathways. Together these studies demonstrate the importance of non-neuronal cells in the assembly of specialized auditory brainstem circuits.

  20. Long Latency Auditory Evoked Potentials during Meditation.

    Science.gov (United States)

    Telles, Shirley; Deepeshwar, Singh; Naveen, Kalkuni Visweswaraiah; Pailoor, Subramanya

    2015-10-01

    The auditory sensory pathway has been studied in meditators, using midlatency and short latency auditory evoked potentials. The present study evaluated long latency auditory evoked potentials (LLAEPs) during meditation. Sixty male participants, aged between 18 and 31 years (group mean±SD, 20.5±3.8 years), were assessed in 4 mental states based on descriptions in the traditional texts. They were (a) random thinking, (b) nonmeditative focusing, (c) meditative focusing, and (d) meditation. The order of the sessions was randomly assigned. The LLAEP components studied were P1 (40-60 ms), N1 (75-115 ms), P2 (120-180 ms), and N2 (180-280 ms). For each component, the peak amplitude and peak latency were measured from the prestimulus baseline. There was significant decrease in the peak latency of the P2 component during and after meditation (Pmeditation facilitates the processing of information in the auditory association cortex, whereas the number of neurons recruited was smaller in random thinking and non-meditative focused thinking, at the level of the secondary auditory cortex, auditory association cortex and anterior cingulate cortex. © EEG and Clinical Neuroscience Society (ECNS) 2014.

  1. Speech Evoked Auditory Brainstem Response in Stuttering

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    Ali Akbar Tahaei

    2014-01-01

    Full Text Available Auditory processing deficits have been hypothesized as an underlying mechanism for stuttering. Previous studies have demonstrated abnormal responses in subjects with persistent developmental stuttering (PDS at the higher level of the central auditory system using speech stimuli. Recently, the potential usefulness of speech evoked auditory brainstem responses in central auditory processing disorders has been emphasized. The current study used the speech evoked ABR to investigate the hypothesis that subjects with PDS have specific auditory perceptual dysfunction. Objectives. To determine whether brainstem responses to speech stimuli differ between PDS subjects and normal fluent speakers. Methods. Twenty-five subjects with PDS participated in this study. The speech-ABRs were elicited by the 5-formant synthesized syllable/da/, with duration of 40 ms. Results. There were significant group differences for the onset and offset transient peaks. Subjects with PDS had longer latencies for the onset and offset peaks relative to the control group. Conclusions. Subjects with PDS showed a deficient neural timing in the early stages of the auditory pathway consistent with temporal processing deficits and their abnormal timing may underlie to their disfluency.

  2. Investigating bottom-up auditory attention

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    Emine Merve Kaya

    2014-05-01

    Full Text Available Bottom-up attention is a sensory-driven selection mechanism that directs perception towards a subset of the stimulus that is considered salient, or attention-grabbing. Most studies of bottom-up auditory attention have adapted frameworks similar to visual attention models whereby local or global contrast is a central concept in defining salient elements in a scene. In the current study, we take a more fundamental approach to modeling auditory attention; providing the first examination of the space of auditory saliency spanning pitch, intensity and timbre; and shedding light on complex interactions among these features. Informed by psychoacoustic results, we develop a computational model of auditory saliency implementing a novel attentional framework, guided by processes hypothesized to take place in the auditory pathway. In particular, the model tests the hypothesis that perception tracks the evolution of sound events in a multidimensional feature space, and flags any deviation from background statistics as salient. Predictions from the model corroborate the relationship between bottom-up auditory attention and statistical inference, and argues for a potential role of predictive coding as mechanism for saliency detection in acoustic scenes.

  3. Quantifying ecological thresholds from response surfaces

    Science.gov (United States)

    Heather E. Lintz; Bruce McCune; Andrew N. Gray; Katherine A. McCulloh

    2011-01-01

    Ecological thresholds are abrupt changes of ecological state. While an ecological threshold is a widely accepted concept, most empirical methods detect them in time or across geographic space. Although useful, these approaches do not quantify the direct drivers of threshold response. Causal understanding of thresholds detected empirically requires their investigation...

  4. Objective estimation of frequency-specific pure-tone hearing thresholds following bone-conduction hearing aid stimulation.

    Science.gov (United States)

    Rahne, Torsten; Ehelebe, Thomas

    2014-01-01

    Patients suffering from conductive or mixed hearing loss may benefit from bone-conduction hearing systems (BAHS). The amount of amplification provided by the hearing system is selected based on the individual's sensorineural frequency-specific threshold. With patients who are not able to provide thresholds behaviorally, such as young children, objective methods are required to estimate the unaided and aided hearing threshold and thus the success of the hearing system fitting. In a prospective study with ten adult Baha softband users, aided and unaided frequency-specific thresholds were estimated. Aided thresholds to tone bursts via Baha stimulation were obtained behaviorally and electrophysiologically using cortical auditory evoked potentials (CAEPs) and were compared to pure-tone thresholds using routine clinical audiometry. For all stimulation frequencies, the frequency-specific electrophysiological and behavioral hearing thresholds measured with Baha stimulation were highly correlated and not different. Increased thresholds were observed only with the 0.5 kHz Baha stimulation as compared to the pure-tone audiogram. Objective measurement of frequency-specific hearing thresholds with CAEPs is applicable to BAHS users.

  5. Objective Estimation of Frequency-Specific Pure-Tone Hearing Thresholds following Bone-Conduction Hearing Aid Stimulation

    Directory of Open Access Journals (Sweden)

    Torsten Rahne

    2014-01-01

    Full Text Available Patients suffering from conductive or mixed hearing loss may benefit from bone-conduction hearing systems (BAHS. The amount of amplification provided by the hearing system is selected based on the individual’s sensorineural frequency-specific threshold. With patients who are not able to provide thresholds behaviorally, such as young children, objective methods are required to estimate the unaided and aided hearing threshold and thus the success of the hearing system fitting. In a prospective study with ten adult Baha softband users, aided and unaided frequency-specific thresholds were estimated. Aided thresholds to tone bursts via Baha stimulation were obtained behaviorally and electrophysiologically using cortical auditory evoked potentials (CAEPs and were compared to pure-tone thresholds using routine clinical audiometry. For all stimulation frequencies, the frequency-specific electrophysiological and behavioral hearing thresholds measured with Baha stimulation were highly correlated and not different. Increased thresholds were observed only with the 0.5 kHz Baha stimulation as compared to the pure-tone audiogram. Objective measurement of frequency-specific hearing thresholds with CAEPs is applicable to BAHS users.

  6. Reference-Free Assessment of Speech Intelligibility Using Bispectrum of an Auditory Neurogram.

    Science.gov (United States)

    Hossain, Mohammad E; Jassim, Wissam A; Zilany, Muhammad S A

    2016-01-01

    Sensorineural hearing loss occurs due to damage to the inner and outer hair cells of the peripheral auditory system. Hearing loss can cause decreases in audibility, dynamic range, frequency and temporal resolution of the auditory system, and all of these effects are known to affect speech intelligibility. In this study, a new reference-free speech intelligibility metric is proposed using 2-D neurograms constructed from the output of a computational model of the auditory periphery. The responses of the auditory-nerve fibers with a wide range of characteristic frequencies were simulated to construct neurograms. The features of the neurograms were extracted using third-order statistics referred to as bispectrum. The phase coupling of neurogram bispectrum provides a unique insight for the presence (or deficit) of supra-threshold nonlinearities beyond audibility for listeners with normal hearing (or hearing loss). The speech intelligibility scores predicted by the proposed method were compared to the behavioral scores for listeners with normal hearing and hearing loss both in quiet and under noisy background conditions. The results were also compared to the performance of some existing methods. The predicted results showed a good fit with a small error suggesting that the subjective scores can be estimated reliably using the proposed neural-response-based metric. The proposed metric also had a wide dynamic range, and the predicted scores were well-separated as a function of hearing loss. The proposed metric successfully captures the effects of hearing loss and supra-threshold nonlinearities on speech intelligibility. This metric could be applied to evaluate the performance of various speech-processing algorithms designed for hearing aids and cochlear implants.

  7. A point process framework for modeling electrical stimulation of the auditory nerve

    Science.gov (United States)

    Rubinstein, Jay T.; Shea-Brown, Eric

    2012-01-01

    Model-based studies of responses of auditory nerve fibers to electrical stimulation can provide insight into the functioning of cochlear implants. Ideally, these studies can identify limitations in sound processing strategies and lead to improved methods for providing sound information to cochlear implant users. To accomplish this, models must accurately describe spiking activity while avoiding excessive complexity that would preclude large-scale simulations of populations of auditory nerve fibers and obscure insight into the mechanisms that influence neural encoding of sound information. In this spirit, we develop a point process model of individual auditory nerve fibers that provides a compact and accurate description of neural responses to electric stimulation. Inspired by the framework of generalized linear models, the proposed model consists of a cascade of linear and nonlinear stages. We show how each of these stages can be associated with biophysical mechanisms and related to models of neuronal dynamics. Moreover, we derive a semianalytical procedure that uniquely determines each parameter in the model on the basis of fundamental statistics from recordings of single fiber responses to electric stimulation, including threshold, relative spread, jitter, and chronaxie. The model also accounts for refractory and summation effects that influence the responses of auditory nerve fibers to high pulse rate stimulation. Throughout, we compare model predictions to published physiological data of response to high and low pulse rate stimulation. We find that the model, although constructed to fit data from single and paired pulse experiments, can accurately predict responses to unmodulated and modulated pulse train stimuli. We close by performing an ideal observer analysis of simulated spike trains in response to sinusoidally amplitude modulated stimuli and find that carrier pulse rate does not affect modulation detection thresholds. PMID:22673331

  8. Deep transcranial magnetic stimulation add-on for the treatment of auditory hallucinations: a double-blind study

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    Rosenberg Oded

    2012-05-01

    Full Text Available Abstract Background About 25% of schizophrenia patients with auditory hallucinations are refractory to pharmacotherapy and electroconvulsive therapy. We conducted a deep transcranial magnetic stimulation (TMS pilot study in order to evaluate the potential clinical benefit of repeated left temporoparietal cortex stimulation in these patients. The results were encouraging, but a sham-controlled study was needed to rule out a placebo effect. Methods A total of 18 schizophrenic patients with refractory auditory hallucinations were recruited, from Beer Yaakov MHC and other hospitals outpatient populations. Patients received 10 daily treatment sessions with low-frequency (1 Hz for 10 min deep TMS applied over the left temporoparietal cortex, using the H1 coil at the intensity of 110% of the motor threshold. Procedure was either real or sham according to patient randomization. Patients were evaluated via the Auditory Hallucinations Rating Scale, Scale for the Assessment of Positive Symptoms-Negative Symptoms, Clinical Global Impressions, and Quality of Life Questionnaire. Results In all, 10 patients completed the treatment (10 TMS sessions. Auditory hallucination scores of both groups improved; however, there was no statistical difference in any of the scales between the active and the sham treated groups. Conclusions Low-frequency deep TMS to the left temporoparietal cortex using the protocol mentioned above has no statistically significant effect on auditory hallucinations or the other clinical scales measured in schizophrenic patients. Trial Registration Clinicaltrials.gov identifier: NCT00564096.

  9. Amphibious auditory evoked potentials in four North American Testudines genera spanning the aquatic-terrestrial spectrum.

    Science.gov (United States)

    Zeyl, Jeffrey N; Johnston, Carol E

    2015-10-01

    Animals exhibit unique hearing adaptations in relation to the habitat media in which they reside. This study was a comparative analysis of auditory specialization in relation to habitat medium in Testudines, a taxon that includes both highly aquatic and fully terrestrial members. Evoked potential audiograms were collected in four species groups representing diversity along the aquatic-terrestrial spectrum: terrestrial and fossorial Gopherus polyphemus, terrestrial Terrapene carolina carolina, and aquatic Trachemys scripta and Sternotherus (S. odoratus and S. minor). Additionally, underwater sensitivity was tested in T. c. carolina, T. scripta, and Sternotherus with tympana submerged just below the water surface. In aerial audiograms, T. c. carolina were most sensitive, with thresholds 18 dB lower than Sternotherus. At 100-300 Hz, thresholds in T. c. carolina, G. polyphemus, and T. scripta were similar to each other. At 400-800 Hz, G. polyphemus thresholds were elevated to 11 dB above T. c. carolina. The underwater audiograms of T. c. carolina, T. scripta, and Sternotherus were similar. The results suggest aerial hearing adaptations in emydids and high-frequency hearing loss associated with seismic vibration detection in G. polyphemus. The underwater audiogram of T. c. carolina could reflect retention of ancestral aquatic auditory function.

  10. Suppressed Visual Looming Stimuli are Not Integrated with Auditory Looming Signals: Evidence from Continuous Fash Suppression

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    Pieter Moors

    2015-02-01

    Full Text Available Previous studies using binocular rivalry have shown that signals in a modality other than the visual can bias dominance durations depending on their congruency with the rivaling stimuli. More recently, studies using continuous flash suppression (CFS have reported that multisensory integration influences how long visual stimuli remain suppressed. In this study, using CFS, we examined whether the contrast thresholds for detecting visual looming stimuli are influenced by a congruent auditory stimulus. In Experiment 1, we show that a looming visual stimulus can result in lower detection thresholds compared to a static concentric grating, but that auditory tone pips congruent with the looming stimulus did not lower suppression thresholds any further. In Experiments 2, 3, and 4, we again observed no advantage for congruent multisensory stimuli. These results add to our understanding of the conditions under which multisensory integration is possible, and suggest that certain forms of multisensory integration are not evident when the visual stimulus is suppressed from awareness using CFS.

  11. Prolonged auditory brainstem responses in infants with autism

    Science.gov (United States)

    Miron, Oren; Ari‐Even Roth, Daphne; Gabis, Lidia V.; Henkin, Yael; Shefer, Shahar; Dinstein, Ilan

    2015-01-01

    Numerous studies have attempted to identify early physiological abnormalities in infants and toddlers who later develop autism spectrum disorder (ASD). One potential measure of early neurophysiology is the auditory brainstem response (ABR), which has been reported to exhibit prolonged latencies in children with ASD. We examined whether prolonged ABR latencies appear in infancy, before the onset of ASD symptoms, and irrespective of hearing thresholds. To determine how early in development these differences appear, we retrospectively examined clinical ABR recordings of infants who were later diagnosed with ASD. Of the 118 children in the participant pool, 48 were excluded due to elevated ABR thresholds, genetic aberrations, or old testing age, leaving a sample of 70 children: 30 of which were tested at 0–3 months, and 40 were tested at toddlerhood (1.5–3.5 years). In the infant group, the ABR wave‐V was significantly prolonged in those who later developed ASD as compared with case‐matched controls (n = 30). Classification of infants who later developed ASD and case‐matched controls using this measure enabled accurate identification of ASD infants with 80% specificity and 70% sensitivity. In the group of toddlers with ASD, absolute and interpeak latencies were prolonged compared to clinical norms. Findings indicate that ABR latencies are significantly prolonged in infants who are later diagnosed with ASD irrespective of their hearing thresholds; suggesting that abnormal responses might be detected soon after birth. Further research is needed to determine if ABR might be a valid marker for ASD risk. Autism Res 2016, 9: 689–695. © 2015 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research PMID:26477791

  12. Predictive coding of visual-auditory and motor-auditory events: An electrophysiological study

    NARCIS (Netherlands)

    Stekelenburg, J.J.; Vroomen, J.

    2015-01-01

    The amplitude of auditory components of the event-related potential (ERP) is attenuated when sounds are self-generated compared to externally generated sounds. This effect has been ascribed to internal forward modals predicting the sensory consequences of one’s own motor actions. Auditory potentials

  13. Amygdala and auditory cortex exhibit distinct sensitivity to relevant acoustic features of auditory emotions.

    Science.gov (United States)

    Pannese, Alessia; Grandjean, Didier; Frühholz, Sascha

    2016-12-01

    Discriminating between auditory signals of different affective value is critical to successful social interaction. It is commonly held that acoustic decoding of such signals occurs in the auditory system, whereas affective decoding occurs in the amygdala. However, given that the amygdala receives direct subcortical projections that bypass the auditory cortex, it is possible that some acoustic decoding occurs in the amygdala as well, when the acoustic features are relevant for affective discrimination. We tested this hypothesis by combining functional neuroimaging with the neurophysiological phenomena of repetition suppression (RS) and repetition enhancement (RE) in human listeners. Our results show that both amygdala and auditory cortex responded differentially to physical voice features, suggesting that the amygdala and auditory cortex decode the affective quality of the voice not only by processing the emotional content from previously processed acoustic features, but also by processing the acoustic features themselves, when these are relevant to the identification of the voice's affective value. Specifically, we found that the auditory cortex is sensitive to spectral high-frequency voice cues when discriminating vocal anger from vocal fear and joy, whereas the amygdala is sensitive to vocal pitch when discriminating between negative vocal emotions (i.e., anger and fear). Vocal pitch is an instantaneously recognized voice feature, which is potentially transferred to the amygdala by direct subcortical projections. These results together provide evidence that, besides the auditory cortex, the amygdala too processes acoustic information, when this is relevant to the discrimination of auditory emotions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Comparative observation of protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure.

    Science.gov (United States)

    Li, Chao-jun; Zhu, Pei-fang; Liu, Zhao-hua; Wang, Zheng-guo; Yang, Cheng; Chen, Hai-bin; Ning, Xin; Zhou, Ji-hong; Chen, Jian

    2006-08-01

    To explore the protective effects of earplug and barrel on auditory organs of guinea pigs exposed to experimental blast underpressure (BUP). The hearing thresholds of the guinea pigs were assessed with auditory brainstem responses (ABR). The traumatic levels of tympanic membrane and ossicular chain were observed under stereo-microscope. The rate of outer hair cells (OHCs) loss was analyzed using a light microscope. The changes of guinea pigs protected with barrel and earplug were compared with those of the control group without any protection. An important ABR threshold shift of the guinea pigs without any protection was detected from 8h to 14d after being exposed to BUP with a peak ranging from -64.5 kPa to -69.3 kPa ( Pearplug had lower ABR threshold and total OHCs loss rate compared with the animals without any protection (Pearplug (Pearplug and barrel have protective effects against BUP-induced trauma on auditory organs of the guinea pigs and the protective effects of barrel are better than those of earplug.

  15. Efficacy of auditory training in elderly subjects

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    Aline Albuquerque Morais

    2015-05-01

    Full Text Available Auditory training (AT  has been used for auditory rehabilitation in elderly individuals and is an effective tool for optimizing speech processing in this population. However, it is necessary to distinguish training-related improvements from placebo and test-retest effects. Thus, we investigated the efficacy of short-term auditory training (acoustically controlled auditory training - ACAT in elderly subjects through behavioral measures and P300. Sixteen elderly individuals with APD received an initial evaluation (evaluation 1 - E1 consisting of behavioral and electrophysiological tests (P300 evoked by tone burst and speech sounds to evaluate their auditory processing. The individuals were divided into two groups. The Active Control Group [ACG (n=8] underwent placebo training. The Passive Control Group [PCG (n=8] did not receive any intervention. After 12 weeks, the subjects were  revaluated (evaluation 2 - E2. Then, all of the subjects underwent ACAT. Following another 12 weeks (8 training sessions, they underwent the final evaluation (evaluation 3 – E3. There was no significant difference between E1 and E2 in the behavioral test [F(9.6=0,.6 p=0.92, λ de Wilks=0.65] or P300 [F(8.7=2.11, p=0.17, λ de Wilks=0.29] (discarding the presence of placebo effects and test-retest. A significant improvement was observed between the pre- and post-ACAT conditions (E2 and E3 for all auditory skills according to the behavioral methods [F(4.27=0.18, p=0.94, λ de Wilks=0.97]. However, the same result was not observed for P300 in any condition. There was no significant difference between P300 stimuli. The ACAT improved the behavioral performance of the elderly for all auditory skills and was an effective method for hearing rehabilitation.

  16. Auditory sustained field responses to periodic noise

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    Keceli Sumru

    2012-01-01

    Full Text Available Abstract Background Auditory sustained responses have been recently suggested to reflect neural processing of speech sounds in the auditory cortex. As periodic fluctuations below the pitch range are important for speech perception, it is necessary to investigate how low frequency periodic sounds are processed in the human auditory cortex. Auditory sustained responses have been shown to be sensitive to temporal regularity but the relationship between the amplitudes of auditory evoked sustained responses and the repetitive rates of auditory inputs remains elusive. As the temporal and spectral features of sounds enhance different components of sustained responses, previous studies with click trains and vowel stimuli presented diverging results. In order to investigate the effect of repetition rate on cortical responses, we analyzed the auditory sustained fields evoked by periodic and aperiodic noises using magnetoencephalography. Results Sustained fields were elicited by white noise and repeating frozen noise stimuli with repetition rates of 5-, 10-, 50-, 200- and 500 Hz. The sustained field amplitudes were significantly larger for all the periodic stimuli than for white noise. Although the sustained field amplitudes showed a rising and falling pattern within the repetition rate range, the response amplitudes to 5 Hz repetition rate were significantly larger than to 500 Hz. Conclusions The enhanced sustained field responses to periodic noises show that cortical sensitivity to periodic sounds is maintained for a wide range of repetition rates. Persistence of periodicity sensitivity below the pitch range suggests that in addition to processing the fundamental frequency of voice, sustained field generators can also resolve low frequency temporal modulations in speech envelope.

  17. A Decline in Response Variability Improves Neural Signal Detection during Auditory Task Performance.

    Science.gov (United States)

    von Trapp, Gardiner; Buran, Bradley N; Sen, Kamal; Semple, Malcolm N; Sanes, Dan H

    2016-10-26

    The detection of a sensory stimulus arises from a significant change in neural activity, but a sensory neuron's response is rarely identical to successive presentations of the same stimulus. Large trial-to-trial variability would limit the central nervous system's ability to reliably detect a stimulus, presumably affecting perceptual performance. However, if response variability were to decrease while firing rate remained constant, then neural sensitivity could improve. Here, we asked whether engagement in an auditory detection task can modulate response variability, thereby increasing neural sensitivity. We recorded telemetrically from the core auditory cortex of gerbils, both while they engaged in an amplitude-modulation detection task and while they sat quietly listening to the identical stimuli. Using a signal detection theory framework, we found that neural sensitivity was improved during task performance, and this improvement was closely associated with a decrease in response variability. Moreover, units with the greatest change in response variability had absolute neural thresholds most closely aligned with simultaneously measured perceptual thresholds. Our findings suggest that the limitations imposed by response variability diminish during task performance, thereby improving the sensitivity of neural encoding and potentially leading to better perceptual sensitivity. The detection of a sensory stimulus arises from a significant change in neural activity. However, trial-to-trial variability of the neural response may limit perceptual performance. If the neural response to a stimulus is quite variable, then the response on a given trial could be confused with the pattern of neural activity generated when the stimulus is absent. Therefore, a neural mechanism that served to reduce response variability would allow for better stimulus detection. By recording from the cortex of freely moving animals engaged in an auditory detection task, we found that variability

  18. Elicitation threshold of cobalt chloride

    DEFF Research Database (Denmark)

    Fischer, Louise A; Johansen, Jeanne D; Voelund, Aage

    2016-01-01

    BACKGROUND: Cobalt is a strong skin sensitizer (grade 5 of 5 in the guinea-pig maximization test) that is used in various industrial and consumer applications. To prevent sensitization to cobalt and elicitation of allergic cobalt dermatitis, information about the elicitation threshold level...... of cobalt is important. OBJECTIVE: To identify the dermatitis elicitation threshold levels in cobalt-allergic individuals. MATERIALS AND METHODS: Published patch test dose-response studies were reviewed to determine the elicitation dose (ED) levels in dermatitis patients with a previous positive patch test...... reaction to cobalt. A logistic dose-response model was applied to data collected from the published literature to estimate ED values. The 95% confidence interval (CI) for the ratio of mean doses that can elicit a reaction in 10% (ED(10)) of a population was calculated with Fieller's method. RESULTS...

  19. Estudo de caso: neuropatia auditiva Auditory neuropathy: a study case

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    Viviane M. Parra

    2003-03-01

    patient with auditory neuropathy attended at "Centro de Docência e Pesquisa em Fonoaudiologia da Faculdade de Medicina da Universidade de São Paulo", correlating the study data with literature. The patient described is a 24 year-old person, with auditory neuropathy diagnosis, evaluated in our center in 2001. Interview, tonal audiometry thresholds, speech recognition, timpanometry, otoacustic emissions (OAEs and auditory brainstem responses (ABR were applied. In this case we observed incompatible results in the tonal audiometric threshold and speech recognition tests, with objectives tests like OAEs and ABR, in which we found a hearing loss with important changes in the speech recognition test, of OAEs present and abnormal ABR. These data suggest a normal cochlear function and abnormal neural synchrony.

  20. Altered cortical and subcortical connectivity due to infrasound administered near the hearing threshold – Evidence from fMRI

    Science.gov (United States)

    Weichenberger, Markus; Bauer, Martin; Kühler, Robert; Hensel, Johannes; Forlim, Caroline Garcia; Ihlenfeld, Albrecht; Ittermann, Bernd; Gallinat, Jürgen; Koch, Christian; Kühn, Simone

    2017-01-01

    In the present study, the brain’s response towards near- and supra-threshold infrasound (IS) stimulation (sound frequency near-threshold) as well as the right superior frontal gyrus (rSFG) during the near-threshold condition. In summary, this study is the first to demonstrate that infrasound near the hearing threshold may induce changes of neural activity across several brain regions, some of which are known to be involved in auditory processing, while others are regarded as keyplayers in emotional and autonomic control. These findings thus allow us to speculate on how continuous exposure to (sub-)liminal IS could exert a pathogenic influence on the organism, yet further (especially longitudinal) studies are required in order to substantialize these findings. PMID:28403175

  1. Altered cortical and subcortical connectivity due to infrasound administered near the hearing threshold - Evidence from fMRI.

    Science.gov (United States)

    Weichenberger, Markus; Bauer, Martin; Kühler, Robert; Hensel, Johannes; Forlim, Caroline Garcia; Ihlenfeld, Albrecht; Ittermann, Bernd; Gallinat, Jürgen; Koch, Christian; Kühn, Simone

    2017-01-01

    In the present study, the brain's response towards near- and supra-threshold infrasound (IS) stimulation (sound frequency near-threshold) as well as the right superior frontal gyrus (rSFG) during the near-threshold condition. In summary, this study is the first to demonstrate that infrasound near the hearing threshold may induce changes of neural activity across several brain regions, some of which are known to be involved in auditory processing, while others are regarded as keyplayers in emotional and autonomic control. These findings thus allow us to speculate on how continuous exposure to (sub-)liminal IS could exert a pathogenic influence on the organism, yet further (especially longitudinal) studies are required in order to substantialize these findings.

  2. Altered cortical and subcortical connectivity due to infrasound administered near the hearing threshold - Evidence from fMRI.

    Directory of Open Access Journals (Sweden)

    Markus Weichenberger

    Full Text Available In the present study, the brain's response towards near- and supra-threshold infrasound (IS stimulation (sound frequency near-threshold as well as the right superior frontal gyrus (rSFG during the near-threshold condition. In summary, this study is the first to demonstrate that infrasound near the hearing threshold may induce changes of neural activity across several brain regions, some of which are known to be involved in auditory processing, while others are regarded as keyplayers in emotional and autonomic control. These findings thus allow us to speculate on how continuous exposure to (sub-liminal IS could exert a pathogenic influence on the organism, yet further (especially longitudinal studies are required in order to substantialize these findings.

  3. Observations on auditory learning in amplitude- and frequency-modulation rate discrimination

    DEFF Research Database (Denmark)

    Hoffmann, Pablo F.

    2010-01-01

    . One of the key issues when designing such training systems is in the assessment of transfer of learning. In this study we present data on the learning of an auditory task involving sinusoidal amplitude- and frequency-modulated tones. Modulation rate discrimination thresholds were measured during pre......-training, training, a post-training stages. During training, listeners were divided into two groups; one group trained on amplitude-modulation rate discrimination and the other group trained on frequency-modulation rate discrimination. Results will be discussed in terms of their implications for training...... applications by addressing the transfer of learning across carrier frequency, modulation rate, and modulation type....

  4. Auditory and motor imagery modulate learning in music performance

    Science.gov (United States)

    Brown, Rachel M.; Palmer, Caroline

    2013-01-01

    Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians' encoding (during Learning, as they practiced novel melodies), and retrieval (during Recall of those melodies). Pianists learned melodies by listening without performing (auditory learning) or performing without sound (motor learning); following Learning, pianists performed the melodies from memory with auditory feedback (Recall). During either Learning (Experiment 1) or Recall (Experiment 2), pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced) and temporal regularity (variability of quarter-note interonset intervals) were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists' pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2). Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1): Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2): Higher auditory imagery skill predicted greater temporal regularity during Recall in the presence of

  5. Auditory and motor imagery modulate learning in music performance.

    Science.gov (United States)

    Brown, Rachel M; Palmer, Caroline

    2013-01-01

    Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians' encoding (during Learning, as they practiced novel melodies), and retrieval (during Recall of those melodies). Pianists learned melodies by listening without performing (auditory learning) or performing without sound (motor learning); following Learning, pianists performed the melodies from memory with auditory feedback (Recall). During either Learning (Experiment 1) or Recall (Experiment 2), pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced) and temporal regularity (variability of quarter-note interonset intervals) were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists' pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2). Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1): Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2): Higher auditory imagery skill predicted greater temporal regularity during Recall in the presence of

  6. Experience and information loss in auditory and visual memory.

    Science.gov (United States)

    Gloede, Michele E; Paulauskas, Emily E; Gregg, Melissa K

    2017-07-01

    Recent studies show that recognition memory for sounds is inferior to memory for pictures. Four experiments were conducted to examine the nature of auditory and visual memory. Experiments 1-3 were conducted to evaluate the role of experience in auditory and visual memory. Participants received a study phase with pictures/sounds, followed by a recognition memory test. Participants then completed auditory training with each of the sounds, followed by a second memory test. Despite auditory training in Experiments 1 and 2, visual memory was superior to auditory memory. In Experiment 3, we found that it is possible to improve auditory memory, but only after 3 days of specific auditory training and 3 days of visual memory decay. We examined the time course of information loss in auditory and visual memory in Experiment 4 and found a trade-off between visual and auditory recognition memory: Visual memory appears to have a larger capacity, while auditory memory is more enduring. Our results indicate that visual and auditory memory are inherently different memory systems and that differences in visual and auditory recognition memory performance may be due to the different amounts of experience with visual and auditory information, as well as structurally different neural circuitry specialized for information retention.

  7. Current status of auditory aging and anti-aging research.

    Science.gov (United States)

    Ruan, Qingwei; Ma, Cheng; Zhang, Ruxin; Yu, Zhuowei

    2014-01-01

    The development of presbycusis, or age-related hearing loss, is determined by a combination of genetic and environmental factors. The auditory periphery exhibits a progressive bilateral, symmetrical reduction of auditory sensitivity to sound from high to low frequencies. The central auditory nervous system shows symptoms of decline in age-related cognitive abilities, including difficulties in speech discrimination and reduced central auditory processing, ultimately resulting in auditory perceptual abnormalities. The pathophysiological mechanisms of presbycusis include excitotoxicity, oxidative stress, inflammation, aging and oxidative stress-induced DNA damage that results in apoptosis in the auditory pathway. However, the originating signals that trigger these mechanisms remain unclear. For instance, it is still unknown whether insulin is involved in auditory aging. Auditory aging has preclinical lesions, which manifest as asymptomatic loss of periphery auditory nerves and changes in the plasticity of the central auditory nervous system. Currently, the diagnosis of preclinical, reversible lesions depends on the detection of auditory impairment by functional imaging, and the identification of physiological and molecular biological markers. However, despite recent improvements in the application of these markers, they remain under-utilized in clinical practice. The application of antisenescent approaches to the prevention of auditory aging has produced inconsistent results. Future research will focus on the identification of markers for the diagnosis of preclinical auditory aging and the development of effective interventions. © 2013 Japan Geriatrics Society.

  8. Perceptual Plasticity for Auditory Object Recognition

    Science.gov (United States)

    Heald, Shannon L. M.; Van Hedger, Stephen C.; Nusbaum, Howard C.

    2017-01-01

    In our auditory environment, we rarely experience the exact acoustic waveform twice. This is especially true for communicative signals that have meaning for listeners. In speech and music, the acoustic signal changes as a function of the talker (or instrument), speaking (or playing) rate, and room acoustics, to name a few factors. Yet, despite this acoustic variability, we are able to recognize a sentence or melody as the same across various kinds of acoustic inputs and determine meaning based on listening goals, expectations, context, and experience. The recognition process relates acoustic signals to prior experience despite variability in signal-relevant and signal-irrelevant acoustic properties, some of which could be considered as “noise” in service of a recognition goal. However, some acoustic variability, if systematic, is lawful and can be exploited by listeners to aid in recognition. Perceivable changes in systematic variability can herald a need for listeners to reorganize perception and reorient their attention to more immediately signal-relevant cues. This view is not incorporated currently in many extant theories of auditory perception, which traditionally reduce psychological or neural representations of perceptual objects and the processes that act on them to static entities. While this reduction is likely done for the sake of empirical tractability, such a reduction may seriously distort the perceptual process to be modeled. We argue that perceptual representations, as well as the processes underlying perception, are dynamically determined by an interaction between the uncertainty of the auditory signal and constraints of context. This suggests that the process of auditory recognition is highly context-dependent in that the identity of a given auditory object may be intrinsically tied to its preceding context. To argue for the flexible neural and psychological updating of sound-to-meaning mappings across speech and music, we draw upon examples

  9. Perceptual Plasticity for Auditory Object Recognition

    Directory of Open Access Journals (Sweden)

    Shannon L. M. Heald

    2017-05-01

    Full Text Available In our auditory environment, we rarely experience the exact acoustic waveform twice. This is especially true for communicative signals that have meaning for listeners. In speech and music, the acoustic signal changes as a function of the talker (or instrument, speaking (or playing rate, and room acoustics, to name a few factors. Yet, despite this acoustic variability, we are able to recognize a sentence or melody as the same across various kinds of acoustic inputs and determine meaning based on listening goals, expectations, context, and experience. The recognition process relates acoustic signals to prior experience despite variability in signal-relevant and signal-irrelevant acoustic properties, some of which could be considered as “noise” in service of a recognition goal. However, some acoustic variability, if systematic, is lawful and can be exploited by listeners to aid in recognition. Perceivable changes in systematic variability can herald a need for listeners to reorganize perception and reorient their attention to more immediately signal-relevant cues. This view is not incorporated currently in many extant theories of auditory perception, which traditionally reduce psychological or neural representations of perceptual objects and the processes that act on them to static entities. While this reduction is likely done for the sake of empirical tractability, such a reduction may seriously distort the perceptual process to be modeled. We argue that perceptual representations, as well as the processes underlying perception, are dynamically determined by an interaction between the uncertainty of the auditory signal and constraints of context. This suggests that the process of auditory recognition is highly context-dependent in that the identity of a given auditory object may be intrinsically tied to its preceding context. To argue for the flexible neural and psychological updating of sound-to-meaning mappings across speech and music, we

  10. Color difference thresholds in dentistry.

    Science.gov (United States)

    Paravina, Rade D; Ghinea, Razvan; Herrera, Luis J; Bona, Alvaro D; Igiel, Christopher; Linninger, Mercedes; Sakai, Maiko; Takahashi, Hidekazu; Tashkandi, Esam; Perez, Maria del Mar

    2015-01-01

    The aim of this prospective multicenter study was to determine 50:50% perceptibility threshold (PT) and 50:50% acceptability threshold (AT) of dental ceramic under simulated clinical settings. The spectral radiance of 63 monochromatic ceramic specimens was determined using a non-contact spectroradiometer. A total of 60 specimen pairs, divided into 3 sets of 20 specimen pairs (medium to light shades, medium to dark shades, and dark shades), were selected for psychophysical experiment. The coordinating center and seven research sites obtained the Institutional Review Board (IRB) approvals prior the beginning of the experiment. Each research site had 25 observers, divided into five groups of five observers: dentists-D, dental students-S, dental auxiliaries-A, dental technicians-T, and lay persons-L. There were 35 observers per group (five observers per group at each site ×7 sites), for a total of 175 observers. Visual color comparisons were performed using a viewing booth. Takagi-Sugeno-Kang (TSK) fuzzy approximation was used for fitting the data points. The 50:50% PT and 50:50% AT were determined in CIELAB and CIEDE2000. The t-test was used to evaluate the statistical significance in thresholds differences. The CIELAB 50:50% PT was ΔEab  = 1.2, whereas 50:50% AT was ΔEab  = 2.7. Corresponding CIEDE2000 (ΔE00 ) values were 0.8 and 1.8, respectively. 50:50% PT by the observer group revealed differences among groups D, A, T, and L as compared with 50:50% PT for all observers. The 50:50% AT for all observers was statistically different than 50:50% AT in groups T and L. A 50:50% perceptibility and ATs were significantly different. The same is true for differences between two color difference formulas ΔE00 /ΔEab . Observer groups and sites showed high level of statistical difference in all thresholds. Visual color difference thresholds can serve as a quality control tool to guide the selection of esthetic dental materials, evaluate clinical performance, and

  11. Stroke rehabilitation reaches a threshold.

    Directory of Open Access Journals (Sweden)

    Cheol E Han

    2008-08-01

    Full Text Available Motor training with the upper limb affected by stroke partially reverses the loss of cortical representation after lesion and has been proposed to increase spontaneous arm use. Moreover, repeated attempts to use the affected hand in daily activities create a form of practice that can potentially lead to further improvement in motor performance. We thus hypothesized that if motor retraining after stroke increases spontaneous arm use sufficiently, then the patient will enter a virtuous circle in which spontaneous arm use and motor performance reinforce each other. In contrast, if the dose of therapy is not sufficient to bring spontaneous use above threshold, then performance will not increase and the patient will further develop compensatory strategies with the less affected hand. To refine this hypothesis, we developed a computational model of bilateral hand use in arm reaching to study the interactions between adaptive decision making and motor relearning after motor cortex lesion. The model contains a left and a right motor cortex, each controlling the opposite arm, and a single action choice module. The action choice module learns, via reinforcement learning, the value of using each arm for reaching in specific directions. Each motor cortex uses a neural population code to specify the initial direction along which the contralateral hand moves towards a target. The motor cortex learns to minimize directional errors and to maximize neuronal activity for each movement. The derived learning rule accounts for the reversal of the loss of cortical representation after rehabilitation and the increase of this loss after stroke with insufficient rehabilitation. Further, our model exhibits nonlinear and bistable behavior: if natural recovery, motor training, or both, brings performance above a certain threshold, then training can be stopped, as the repeated spontaneous arm use provides a form of motor learning that further bootstraps performance and

  12. Anatomical Pathways for Auditory Memory in Primates

    Directory of Open Access Journals (Sweden)

    Monica Munoz-Lopez

    2010-10-01

    Full Text Available Episodic memory or the ability to store context-rich information about everyday events depends on the hippocampal formation (entorhinal cortex, subiculum, presubiculum, parasubiculum, hippocampus proper, and dentate gyrus. A substantial amount of behavioral-lesion and anatomical studies have contributed to our understanding of the organization of how visual stimuli are retained in episodic memory. However, whether auditory memory is organized similarly is still unclear. One hypothesis is that, like the ‘visual ventral stream’ for which the connections of the inferior temporal gyrus with the perirhinal cortex are necessary for visual recognition in monkeys, direct connections between the auditory association areas of the superior temporal gyrus and the hippocampal formation and with the parahippocampal region (temporal pole, perhirinal, and posterior parahippocampal cortices might also underlie recognition memory for sounds. Alternatively, the anatomical organization of memory could be different in audition. This alternative ‘indirect stream’ hypothesis posits that, unlike the visual association cortex, the majority of auditory association cortex makes one or more synapses in intermediate, polymodal areas, where they may integrate information from other sensory modalities, before reaching the medial temporal memory system. This review considers anatomical studies that can support either one or both hypotheses – focusing on anatomical studies on the primate brain that have reported not only direct auditory association connections with medial temporal areas, but, importantly, also possible indirect pathways for auditory information to reach the medial temporal lobe memory system.

  13. The Harmonic Organization of Auditory Cortex

    Directory of Open Access Journals (Sweden)

    Xiaoqin eWang

    2013-12-01

    Full Text Available A fundamental structure of sounds encountered in the natural environment is the harmonicity. Harmonicity is an essential component of music found in all cultures. It is also a unique feature of vocal communication sounds such as human speech and animal vocalizations. Harmonics in sounds are produced by a variety of acoustic generators and reflectors in the natural environment, including vocal apparatuses of humans and animal species as well as music instruments of many types. We live in an acoustic world full of harmonicity. Given the widespread existence of the harmonicity in many aspects of the hearing environment, it is natural to expect that it be reflected in the evolution and development of the auditory systems of both humans and animals, in particular the auditory cortex. Recent neuroimaging and neurophysiology experiments have identified regions of non-primary auditory cortex in humans and non-human primates that have selective responses to harmonic pitches. Accumulating evidence has also shown that neurons in many regions of the auditory cortex exhibit characteristic responses to harmonically related frequencies beyond the range of pitch. Together, these findings suggest that a fundamental organizational principle of auditory cortex is based on the harmonicity. Such an organization likely plays an important role in music processing by the brain. It may also form the basis of the preference for particular classes of music and voice sounds.

  14. The harmonic organization of auditory cortex

    Science.gov (United States)

    Wang, Xiaoqin

    2013-01-01

    A fundamental structure of sounds encountered in the natural environment is the harmonicity. Harmonicity is an essential component of music found in all cultures. It is also a unique feature of vocal communication sounds such as human speech and animal vocalizations. Harmonics in sounds are produced by a variety of acoustic generators and reflectors in the natural environment, including vocal apparatuses of humans and animal species as well as music instruments of many types. We live in an acoustic world full of harmonicity. Given the widespread existence of the harmonicity in many aspects of the hearing environment, it is natural to expect that it be reflected in the evolution and development of the auditory systems of both humans and animals, in particular the auditory cortex. Recent neuroimaging and neurophysiology experiments have identified regions of non-primary auditory cortex in humans and non-human primates that have selective responses to harmonic pitches. Accumulating evidence has also shown that neurons in many regions of the auditory cortex exhibit characteristic responses to harmonically related frequencies beyond the range of pitch. Together, these findings suggest that a fundamental organizational principle of auditory cortex is based on the harmonicity. Such an organization likely plays an important role in music processing by the brain. It may also form the basis of the preference for particular classes of music and voice sounds. PMID:24381544

  15. Effects of Caffeine on Auditory Brainstem Response

    Directory of Open Access Journals (Sweden)

    Saleheh Soleimanian

    2008-06-01

    Full Text Available Background and Aim: Blocking of the adenosine receptor in central nervous system by caffeine can lead to increasing the level of neurotransmitters like glutamate. As the adenosine receptors are present in almost all brain areas like central auditory pathway, it seems caffeine can change conduction in this way. The purpose of this study was to evaluate the effects of caffeine on latency and amplitude of auditory brainstem response(ABR.Materials and Methods: In this clinical trial study 43 normal 18-25 years old male students were participated. The subjects consumed 0, 2 and 3 mg/kg BW caffeine in three different sessions. Auditory brainstem responses were recorded before and 30 minute after caffeine consumption. The results were analyzed by Friedman and Wilcoxone test to assess the effects of caffeine on auditory brainstem response.Results: Compared to control group the latencies of waves III,V and I-V interpeak interval of the cases decreased significantly after 2 and 3mg/kg BW caffeine consumption. Wave I latency significantly decreased after 3mg/kg BW caffeine consumption(p<0.01. Conclusion: Increasing of the glutamate level resulted from the adenosine receptor blocking brings about changes in conduction in the central auditory pathway.

  16. Voting on Thresholds for Public Goods

    DEFF Research Database (Denmark)

    Rauchdobler, Julian; Sausgruber, Rupert; Tyran, Jean-Robert

    2010-01-01

    Introducing a threshold in the sense of a minimal project size transforms a public-good game with an inefficient equilibrium into a coordination game with a set of Pareto-superior equilibria. Thresholds may therefore improve efficiency in the voluntary provision of public goods. In our one......-shot experiment, we find that coordination often fails and exogenously imposed thresholds are ineffective at best and often counterproductive. This holds over a range of threshold levels and refund rates. We test whether thresholds perform better if they are endogenously chosen, i.e., whether a threshold...

  17. Voting on Thresholds for Public Goods

    DEFF Research Database (Denmark)

    Rauchdobler, Julian; Sausgruber, Rupert; Tyran, Jean-Robert

    Introducing a threshold in the sense of a minimal project size transforms a public goods game with an inefficient equilibrium into a coordination game with a set of Pareto-superior equilibria. Thresholds may therefore improve efficiency in the voluntary provision of public goods. In our one......-shot experiment, we find that coordination often fails and exogenously imposed thresholds are ineffective at best and often counter-productive. This holds under a range of threshold levels and refund rates. We test if thresholds perform better if they are endogenously chosen, i.e. if a threshold is approved...

  18. Source reliability in auditory health persuasion : Its antecedents and consequences

    NARCIS (Netherlands)

    Elbert, Sarah P.; Dijkstra, Arie

    2015-01-01

    Persuasive health messages can be presented through an auditory channel, thereby enhancing the salience of the source, making it fundamentally different from written or pictorial information. We focused on the determinants of perceived source reliability in auditory health persuasion by

  19. Intradermal melanocytic nevus of the external auditory canal.

    Science.gov (United States)

    Alves, Renato V; Brandão, Fabiano H; Aquino, José E P; Carvalho, Maria R M S; Giancoli, Suzana M; Younes, Eduado A P

    2005-01-01

    Intradermal nevi are common benign pigmented skin tumors. Their occurrence within the external auditory canal is uncommon. The clinical and pathologic features of an intradermal nevus arising within the external auditory canal are presented, and the literature reviewed.

  20. The effect of background music in auditory health persuasion

    NARCIS (Netherlands)

    Elbert, Sarah; Dijkstra, Arie

    2013-01-01

    In auditory health persuasion, threatening information regarding health is communicated by voice only. One relevant context of auditory persuasion is the addition of background music. There are different mechanisms through which background music might influence persuasion, for example through mood

  1. The role of temporal coherence in auditory stream segregation

    DEFF Research Database (Denmark)

    Christiansen, Simon Krogholt

    The ability to perceptually segregate concurrent sound sources and focus one’s attention on a single source at a time is essential for the ability to use acoustic information. While perceptual experiments have determined a range of acoustic cues that help facilitate auditory stream segregation......, it is not clear how the auditory system realizes the task. This thesis presents a study of the mechanisms involved in auditory stream segregation. Through a combination of psychoacoustic experiments, designed to characterize the influence of acoustic cues on auditory stream formation, and computational models...... of auditory processing, the role of auditory preprocessing and temporal coherence in auditory stream formation was evaluated. The computational model presented in this study assumes that auditory stream segregation occurs when sounds stimulate non-overlapping neural populations in a temporally incoherent...

  2. A study of the high-frequency hearing thresholds of dentistry professionals

    Directory of Open Access Journals (Sweden)

    Lopes, Andréa Cintra

    2012-01-01

    Full Text Available Introduction: In the dentistry practice, dentists are exposed to harmful effects caused by several factors, such as the noise produced by their work instruments. In 1959, the American Dental Association recommended periodical hearing assessments and the use of ear protectors. Aquiring more information regarding dentists', dental nurses', and prosthodontists' hearing abilities is necessary to propose prevention measures and early treatment strategies. Objective: To investigate the auditory thresholds of dentists, dental nurses, and prosthodontists. Method: In this clinical and experimental study, 44 dentists (Group I; GI, 36 dental nurses (Group II; GII, and 28 prosthodontists (Group III; GIII were included, , with a total of 108 professionals. The procedures that were performed included a specific interview, ear canal inspection, conventional and high-frequency threshold audiometry, a speech reception threshold test, and an acoustic impedance test. Results: In the 3 groups that were tested, the comparison between the mean hearing thresholds provided evidence of worsened hearing ability relative to the increase in frequency. For the tritonal mean at 500 to 2,000 Hz and 3,000 to 6,000 Hz, GIII presented the worst thresholds. For the mean of the high frequencies (9,000 and 16,000 Hz, GII presented the worst thresholds. Conclusion: The conventional hearing threshold evaluation did not demonstrate alterations in the 3 groups that were tested; however, the complementary tests such as high-frequency audiometry provided greater efficacy in the early detection of hearing problems, since this population's hearing loss impaired hearing ability at frequencies that are not tested by the conventional tests. Therefore, we emphasize the need of utilizing high-frequency threshold audiometry in the hearing assessment routine in combination with other audiological tests.

  3. Involvement of nitric oxide generation in noise-induced temporary threshold shift in guinea pigs.

    Science.gov (United States)

    Chen, Yuh-Shyang; Tseng, Fen-Yu; Liu, Tien-Chen; Lin-Shiau, Shoei Yn; Hsu, Chuan-Jen

    2005-05-01

    The present study explored the role of endogenous nitric oxide (NO) in the temporary threshold shift caused by acoustic trauma. Guinea pigs were exposed to broadband white noise at a level of 105+/-2dB sound pressure level (SPL) for 10min, causing a temporary threshold shift (TTS). The guinea pigs were divided into six groups (N-1 to N-6) according to survival days after noise exposure (0, 1, 2, 3, 7, 28days). Auditory brainstem responses (ABR) were recorded before noise exposure, immediately after noise exposure and before sacrifice. Immediately after animals were sacrificed, the stria vascularis and the spiral ligament of the lateral wall of each individual cochlea were harvest as a unit and prepared for assay of NO. There was a significant correlation (Pconcentration and final ABR threshold in the noise exposure groups. But the return of ABR threshold to pre-noise-exposed level is early than that of NO concentration. An average 16.2dB threshold shift was found immediately after noise exposure. The threshold returned to the pre-noise-exposed level on the second post-exposure day. Comparing to unexposed control animals, the NO concentration increased nearly threefold immediately following noise exposure and decreased to twofold when the hearing threshold had returned to the pre-noise-exposed level. On the seventh post-exposure day the NO concentration was not different from that in unexposed control animals. Those findings indicate that endogenous NO is generated in the noise-induced temporal threshold shift and its concentration is correlated with the hearing loss.

  4. Auditory filters at low-frequencies

    DEFF Research Database (Denmark)

    Orellana, Carlos Andrés Jurado; Pedersen, Christian Sejer; Møller, Henrik

    2009-01-01

    Prediction and assessment of low-frequency noise problems requires information about the auditory filter characteristics at low-frequencies. Unfortunately, data at low-frequencies is scarce and practically no results have been published for frequencies below 100 Hz. Extrapolation of ERB results...... from previous studies suggests the filter bandwidth keeps decreasing below 100 Hz, although at a relatively lower rate than at higher frequencies. Main characteristics of the auditory filter were studied from below 100 Hz up to 1000 Hz. Center frequencies evaluated were 50, 63, 125, 250, 500, and 1000...... Hz. The notched-noise method was used, with the noise masker at 40 dB spectral density. A rounded exponential auditory filter model (roex(p,r)) was used to fit the masking data. Preliminary data on 1 subject is discussed. Considering the system as a whole (e.g. without removing the assumed middle...

  5. Auditory Alterations in Children Infected by Human Immunodeficiency Virus Verified Through Auditory Processing Test.

    Science.gov (United States)

    Romero, Ana Carla Leite; Alfaya, Lívia Marangoni; Gonçales, Alina Sanches; Frizzo, Ana Claudia Figueiredo; Isaac, Myriam de Lima

    2017-01-01

    Introduction The auditory system of HIV-positive children may have deficits at various levels, such as the high incidence of problems in the middle ear that can cause hearing loss. Objective The objective of this study is to characterize the development of children infected by the Human Immunodeficiency Virus (HIV) in the Simplified Auditory Processing Test (SAPT) and the Staggered Spondaic Word Test. Methods We performed behavioral tests composed of the Simplified Auditory Processing Test and the Portuguese version of the Staggered Spondaic Word Test (SSW). The participants were 15 children infected by HIV, all using antiretroviral medication. Results The children had abnormal auditory processing verified by Simplified Auditory Processing Test and the Portuguese version of SSW. In the Simplified Auditory Processing Test, 60% of the children presented hearing impairment. In the SAPT, the memory test for verbal sounds showed more errors (53.33%); whereas in SSW, 86.67% of the children showed deficiencies indicating deficit in figure-ground, attention, and memory auditory skills. Furthermore, there are more errors in conditions of background noise in both age groups, where most errors were in the left ear in the Group of 8-year-olds, with similar results for the group aged 9 years. Conclusion The high incidence of hearing loss in children with HIV and comorbidity with several biological and environmental factors indicate the need for: 1) familiar and professional awareness of the impact on auditory alteration on the developing and learning of the children with HIV, and 2) access to educational plans and follow-up with multidisciplinary teams as early as possible to minimize the damage caused by auditory deficits.

  6. Auditory and motor imagery modulate learning in music performance

    Directory of Open Access Journals (Sweden)

    Rachel M. Brown

    2013-07-01

    Full Text Available Skilled performers such as athletes or musicians can improve their performance by imagining the actions or sensory outcomes associated with their skill. Performers vary widely in their auditory and motor imagery abilities, and these individual differences influence sensorimotor learning. It is unknown whether imagery abilities influence both memory encoding and retrieval. We examined how auditory and motor imagery abilities influence musicians’ encoding (during Learning, as they practiced novel melodies, and retrieval (during Recall of those melodies. Pianists learned melodies by listening without performing (auditory learning or performing without sound (motor learning; following Learning, pianists performed the melodies from memory with auditory feedback (Recall. During either Learning (Experiment 1 or Recall (Experiment 2, pianists experienced either auditory interference, motor interference, or no interference. Pitch accuracy (percentage of correct pitches produced and temporal regularity (variability of quarter-note interonset intervals were measured at Recall. Independent tests measured auditory and motor imagery skills. Pianists’ pitch accuracy was higher following auditory learning than following motor learning and lower in motor interference conditions (Experiments 1 and 2. Both auditory and motor imagery skills improved pitch accuracy overall. Auditory imagery skills modulated pitch accuracy encoding (Experiment 1: Higher auditory imagery skill corresponded to higher pitch accuracy following auditory learning with auditory or motor interference, and following motor learning with motor or no interference. These findings suggest that auditory imagery abilities decrease vulnerability to interference and compensate for missing auditory feedback at encoding. Auditory imagery skills also influenced temporal regularity at retrieval (Experiment 2: Higher auditory imagery skill predicted greater temporal regularity during Recall in the

  7. Auditory-Perceptual Learning Improves Speech Motor Adaptation in Children

    OpenAIRE

    Shiller, Douglas M.; Rochon, Marie-Lyne

    2014-01-01

    Auditory feedback plays an important role in children’s speech development by providing the child with information about speech outcomes that is used to learn and fine-tune speech motor plans. The use of auditory feedback in speech motor learning has been extensively studied in adults by examining oral motor responses to manipulations of auditory feedback during speech production. Children are also capable of adapting speech motor patterns to perceived changes in auditory feedback, however it...

  8. A virtual auditory environment for investigating the auditory signal processing of realistic sounds

    DEFF Research Database (Denmark)

    Favrot, Sylvain Emmanuel

    A loudspeaker-based virtual auditory environment (VAE) has been developed to provide a realistic versatile research environment for investigating the auditory signal processing in real environments, i.e., considering multiple sound sources and room reverberation. The VAE allows a full control...... of the acoustic scenario in order to systematically study the auditory processing of reverberant sounds. It is based on the ODEON software, which is state-of-the-art software for room acoustic simulations developed at Acoustic Technology, DTU. First, a MATLAB interface to the ODEON software has been developed...

  9. Weights of Exact Threshold Functions

    DEFF Research Database (Denmark)

    Babai, László; Hansen, Kristoffer Arnsfelt; Podolskii, Vladimir V.

    2010-01-01

    We consider Boolean exact threshold functions defined by linear equations, and in general degree d polynomials. We give upper and lower bounds on the maximum magnitude (absolute value) of the coefficients required to represent such functions. These bounds are very close and in the linear case...... and the Boolean cube {0,1} n . In the process we construct new families of ill-conditioned matrices. We further stratify the problem (in the linear case) in terms of the dimension k of the affine subspace spanned by the solutions, and give upper and lower bounds in this case as well. Our bounds here in terms of k...

  10. Auditory Perception of Statistically Blurred Sound Textures

    DEFF Research Database (Denmark)

    McWalter, Richard Ian; MacDonald, Ewen; Dau, Torsten

    Sound textures have been identified as a category of sounds which are processed by the peripheral auditory system and captured with running timeaveraged statistics. Although sound textures are temporally homogeneous, they offer a listener with enough information to identify and differentiate...... sources. This experiment investigated the ability of the auditory system to identify statistically blurred sound textures and the perceptual relationship between sound textures. Identification performance of statistically blurred sound textures presented at a fixed blur increased over those presented...... as a gradual blur. The results suggests that the correct identification of sound textures is influenced by the preceding blurred stimulus. These findings draw parallels to the recognition of blurred images....

  11. Auditory processing in autism spectrum disorder

    DEFF Research Database (Denmark)

    Vlaskamp, Chantal; Oranje, Bob; Madsen, Gitte Falcher

    2017-01-01

    Children with autism spectrum disorders (ASD) often show changes in (automatic) auditory processing. Electrophysiology provides a method to study auditory processing, by investigating event-related potentials such as mismatch negativity (MMN) and P3a-amplitude. However, findings on MMN in autism...... a hyper-responsivity at the attentional level. In addition, as similar MMN deficits are found in schizophrenia, these MMN results may explain some of the frequently reported increased risk of children with ASD to develop schizophrenia later in life. Autism Res 2017, 10: 1857–1865....

  12. The many facets of auditory display

    Science.gov (United States)

    Blattner, Meera M.

    1995-01-01

    In this presentation we will examine some of the ways sound can be used in a virtual world. We make the case that many different types of audio experience are available to us. A full range of audio experiences include: music, speech, real-world sounds, auditory displays, and auditory cues or messages. The technology of recreating real-world sounds through physical modeling has advanced in the past few years allowing better simulation of virtual worlds. Three-dimensional audio has further enriched our sensory experiences.

  13. Auditory brain-stem responses in adrenomyeloneuropathy.

    Science.gov (United States)

    Grimes, A M; Elks, M L; Grunberger, G; Pikus, A M

    1983-09-01

    We studied three patients with adrenomyeloneuropathy. Complete audiologic assessment was obtained: two patients showed unimpaired peripheral hearing and one showed a mild high-frequency hearing loss. Auditory brain-stem responses were abnormal in both ears of all subjects, with one subject showing no response above wave I, and the other two having significant wave I to III and wave III to V interval prolongations. We concluded that auditory brain-stem response testing provides a simple, valid, reliable method for demonstrating neurologic abnormality in adrenomyeloneuropathy even prior to evidence of clinical signs.

  14. Rhythmic walking interaction with auditory feedback

    DEFF Research Database (Denmark)

    Maculewicz, Justyna; Jylhä, Antti; Serafin, Stefania

    2015-01-01

    We present an interactive auditory display for walking with sinusoidal tones or ecological, physically-based synthetic walking sounds. The feedback is either step-based or rhythmic, with constant or adaptive tempo. In a tempo-following experiment, we investigate different interaction modes...... and auditory feedback, based on the MSE between the target and performed tempo, and the stability of the latter. The results indicate that the MSE with ecological sounds is comparable to that with the sinusoidal tones, yet ecological sounds are considered more natural. Adaptive conditions result in stable...

  15. Minimum alveolar concentration threshold of sevoflurane for postoperative dream recall.

    Science.gov (United States)

    Aceto, P; Perilli, V; Lai, C; Sacco, T; Modesti, C; Luca, E; De Santis, P; Sollazzi, L; Antonelli, M

    2015-11-01

    Many factors affect postoperative dream recall, including patient characteristics, type of anesthesia, timing of postoperative interview and stress hormone secretion. Aims of the study were to determine whether Bispectral Index (BIS)-guided anesthesia might decrease sevoflurane minimum alveolar concentration (MAC) when compared with hemodynamically-guided anesthesia, and to search for a MAC threshold useful for preventing arousal, dream recall and implicit memory. One hundred thirty patients undergoing elective thyroidectomy were enrolled. Anesthesia was induced with propofol 2 mg kg(-1), fentanyl 3 mcg kg(-1) and cis-atracurium 0.15 mg kg(-1). For anesthesia maintenance, patients were randomly assigned to one of two groups: a BIS-guided group in which sevoflurane MAC was adjusted on the basis of BIS values, and a hemodynamic parameters (HP)-guided group in which MAC was adjusted based on HP. An auditory recording was presented to patients during anesthesia maintenance. Dream recall and explicit/implicit memory were investigated upon awakening and approximately after 24 h. Mean sevoflurane MAC during auditory presentation was similar in the two groups (0.85 ± 0.16 and 0.87 ± 0.17 [P = 0.53] in BIS-guided and HP-guided groups, respectively). Frequency of dream recall was similar in the two groups: 27% (N. = 17) in BIS-guided group, 18% (N. = 12) in HP-guided group, P = 0.37. In both groups, dream recall was less probable in patients anesthetized with MAC values ≥ 0.9 (area under ROC curve = 0.83, sensitivity = 90%, and specificity = 49%). BIS-guided anesthesia was not able to generate different MAC values compared to HP-guided anesthesia. Independent of the guide used for anesthesia, a sevoflurane MAC over 0.9 was required to prevent postoperative dream recall.

  16. On the synthesis of multiple frequency tone burst stimuli for efficient high frequency auditory brainstem response.

    Science.gov (United States)

    Ellingson, Roger M; Dille, Marilyn L; Leek, Marjorie R; Fausti, Stephen A

    2008-01-01

    The development and digital waveform synthesis of a multiple-frequency tone-burst (MFTB) stimulus is presented. The stimulus is designed to improve the efficiency of monitoring high-frequency auditory-brainstem-response (ABR) hearing thresholds. The pure-tone-based, fractional-octave-bandwidth MFTB supports frequency selective ABR audiometry with a bandwidth that falls between the conventional click and single-frequency tone-burst stimuli. The MFTB is being used to identify high frequency hearing threshold change due to ototoxic medication which most generally starts at the ultra-highest hearing frequencies and progresses downwards but could be useful in general limited-bandwidth testing applications. Included is a Mathcad implementation and analysis of our MFTB synthesis technique and sample performance measurements of the MFTB stimulus configuration used in a clinical research ABR system.

  17. AN EVALUATION OF AUDITORY LEARNING IN FILIAL IMPRINTING

    NARCIS (Netherlands)

    BOLHUIS, JJ; VANKAMPEN, HS

    The characteristics of auditory learning in filial imprinting in precocial birds are reviewed. Numerous studies have demonstrated that the addition of an auditory stimulus improves following of a visual stimulus. This paper evaluates whether there is genuine auditory imprinting, i.e. the formation

  18. Should Children with Auditory Processing Disorders Receive Services in Schools?

    Science.gov (United States)

    Lucker, Jay R.

    2012-01-01

    Many children with problems learning in school can have educational deficits due to underlying auditory processing disorders (APD). For these children, they can be identified as having auditory learning disabilities. Furthermore, auditory learning disabilities is identified as a specific learning disability (SLD) in the IDEA. Educators and…

  19. 21 CFR 874.1090 - Auditory impedance tester.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Auditory impedance tester. 874.1090 Section 874...) MEDICAL DEVICES EAR, NOSE, AND THROAT DEVICES Diagnostic Devices § 874.1090 Auditory impedance tester. (a) Identification. An auditory impedance tester is a device that is intended to change the air pressure in the...

  20. Auditory Temporal Processing as a Specific Deficit among Dyslexic Readers

    Science.gov (United States)

    Fostick, Leah; Bar-El, Sharona; Ram-Tsur, Ronit

    2012-01-01

    The present study focuses on examining the hypothesis that auditory temporal perception deficit is a basic cause for reading disabilities among dyslexics. This hypothesis maintains that reading impairment is caused by a fundamental perceptual deficit in processing rapid auditory or visual stimuli. Since the auditory perception involves a number of…

  1. 76 FR 61655 - Definition of Part 15 Auditory Assistance Device

    Science.gov (United States)

    2011-10-05

    ... COMMISSION 47 CFR Part 15 Definition of Part 15 Auditory Assistance Device AGENCY: Federal Communications Commission. ACTION: Proposed rule. SUMMARY: This document proposes to amend the definition of ``auditory... definition restricts the use of part 15 auditory assistance devices that operate in the 72.0-73.0 MHz, 74.6...

  2. The role of auditory and cognitive factors in understanding speech in noise by normal-hearing older listeners.

    Science.gov (United States)

    Schoof, Tim; Rosen, Stuart

    2014-01-01

    Normal-hearing older adults often experience increased difficulties understanding speech in noise. In addition, they benefit less from amplitude fluctuations in the masker. These difficulties may be attributed to an age-related auditory temporal processing deficit. However, a decline in cognitive processing likely also plays an important role. This study examined the relative contribution of declines in both auditory and cognitive processing to the speech in noise performance in older adults. Participants included older (60-72 years) and younger (19-29 years) adults with normal hearing. Speech reception thresholds (SRTs) were measured for sentences in steady-state speech-shaped noise (SS), 10-Hz sinusoidally amplitude-modulated speech-shaped noise (AM), and two-talker babble. In addition, auditory temporal processing abilities were assessed by measuring thresholds for gap, amplitude-modulation, and frequency-modulation detection. Measures of processing speed, attention, working memory, Text Reception Threshold (a visual analog of the SRT), and reading ability were also obtained. Of primary interest was the extent to which the various measures correlate with listeners' abilities to perceive speech in noise. SRTs were significantly worse for older adults in the presence of two-talker babble but not SS and AM noise. In addition, older adults showed some cognitive processing declines (working memory and processing speed) although no declines in auditory temporal processing. However, working memory and processing speed did not correlate significantly with SRTs in babble. Despite declines in cognitive processing, normal-hearing older adults do not necessarily have problems understanding speech in noise as SRTs in SS and AM noise did not differ significantly between the two groups. Moreover, while older adults had higher SRTs in two-talker babble, this could not be explained by age-related cognitive declines in working memory or processing speed.

  3. The role of auditory and cognitive factors in understanding speech in noise by normal-hearing older listeners

    Directory of Open Access Journals (Sweden)

    Tim eSchoof

    2014-11-01

    Full Text Available Normal-hearing older adults often experience increased difficulties understanding speech in noise. In addition, they benefit less from amplitude fluctuations in the masker. These difficulties may be attributed to an age-related auditory temporal processing deficit. However, a decline in cognitive processing likely also plays an important role. This study examined the relative contribution of declines in both auditory and cognitive processing to the speech in noise performance in older adults. Participants included older (60 - 72 yrs and younger (19 - 29 yrs adults with normal hearing. Speech reception thresholds (SRTs were measured for sentences in steady-state speech-shaped noise (SS, 10-Hz sinusoidally amplitude-modulated speech-shaped noise (AM, and two-talker babble. In addition, auditory temporal processing abilities were assessed by measuring thresholds for gap, amplitude-modulation, and frequency-modulation detection. Measures of processing speed, attention, working memory, Text Reception Threshold (a visual analogue of the SRT, and reading ability were also obtained. Of primary interest was the extent to which the various measures correlate with listeners' abilities to perceive speech in noise.SRTs were significantly worse for older adults in the presence of two-talker babble but not SS and AM noise. In addition, older adults showed some cognitive processing declines (working memory and processing speed although no declines in auditory temporal processing. However, working memory and processing speed did not correlate significantly with SRTs in babble. Despite declines in cognitive processing, normal-hearing older adults do not necessarily have problems understanding speech in noise as SRTs in SS and AM noise did not differ significantly between the two groups. Moreover, while older adults had higher SRTs in two-talker babble, this could not be explained by age-related cognitive declines in working memory or processing speed.

  4. Threshold Concepts in Finance: Student Perspectives

    Science.gov (United States)

    Hoadley, Susan; Kyng, Tim; Tickle, Leonie; Wood, Leigh N.

    2015-01-01

    Finance threshold concepts are the essential conceptual knowledge that underpin well-developed financial capabilities and are central to the mastery of finance. In this paper we investigate threshold concepts in finance from the point of view of students, by establishing the extent to which students are aware of threshold concepts identified by…

  5. Odor threshold determination for 2-nitropropane.

    Science.gov (United States)

    Crawford, G N; Garrison, R P; McFee, D R

    1984-02-01

    The odor threshold of 2-nitropropane (2-NP) has been characterized as not capable of providing warning that air concentrations possibly exceed acceptable guidelines. However, recent testing indicates that the odor threshold is significantly lower than previously thought. In particular, the odor threshold has been indicated by this study to be below the current TLV for 2-NP.

  6. Lowering the CUORE energy threshold

    Science.gov (United States)

    Copello, S.; Alduino, C.; Alfonso, K.; Artusa, D. R.; Avignone, F. T., III.; Azzolini, O.; Banks, T. I.; Bari, G.; Beeman, J. W.; Bellini, F.; Bersani, A.; Biassoni, M.; Branca, A.; Brofferio, C.; Bucci, C.; Camacho, A.; Caminata, A.; Canonica, L.; Cao, X. G.; Capelli, S.; Cappelli, L.; Carbone, L.; Cardani, L.; Carniti, P.; Casali, N.; Cassina, L.; Chiesa, D.; Chott, N.; Clemenza, M.; Cosmelli, C.; Cremonesi, O.; Creswick, R. J.; Cushman, J. S.; D'Addabbo, A.; Dafinei, I.; Davis, C. J.; Dell'Oro, S.; Deninno, M. M.; Di Domizio, S.; Di Vacri, M. L.; Drobizhev, A.; Fang, D. Q.; Faverzani, M.; Fernandes, G.; Ferri, E.; Ferroni, F.; Fiorini, E.; Franceschi, M. A.; Freedman, S. J.; Fujikawa, B. K.; Giachero, A.; Gironi, L.; Giuliani, A.; Gladstone, L.; Gorla, P.; Gotti, C.; Gutierrez, T. D.; Haller, E. E.; Han, K.; Hansen, E.; Heeger, K. M.; Hennings-Yeomans, R.; Hickerson, K. P.; Huang, H. Z.; Kadel, R.; Keppel, G.; Kolomensky, Yu. G.; Leder, A.; Ligi, C.; Lim, K. E.; Liu, X.; Ma, Y. G.; Maino, M.; Marini, L.; Martinez, M.; Maruyama, R. H.; Mei, Y.; Moggi, N.; Morganti, S.; Mosteiro, P. J.; Napolitano, T.; Nones, C.; Norman, E. B.; Nucciotti, A.; O'Donnell, T.; Orio, F.; Ouellet, J. L.; Pagliarone, C. E.; Pallavicini, M.; Palmieri, V.; Pattavina, L.; Pavan, M.; Pessina, G.; Pettinacci, V.; Piperno, G.; Pira, c. C.; Pirro, S.; Pozzi, S.; Previtali, E.; Rosenfeld, C.; Rusconi, C.; Sangiorgio, S.; Santone, D.; Scielzo, N. D.; Singh, V.; Sisti, M.; Smith, A. R.; Taffarello, L.; Tenconi, M.; Terranova, F.; Tomei, C.; Trentalange, S.; Vignati, M.; Wagaarachchi, S. L.; Wang, B. S.; Wang, H. W.; Wilson, J.; Winslow, L. A.; Wise, T.; Woodcraft, A.; Zanotti, L.; Zhang, G. Q.; Zhu, B. X.; Zimmermann, S.; Zucchelli, S.

    2017-09-01

    The Cryogenic Underground Observatory for Rare Events (CUORE) is a ton-scale double beta decay experiment based on TeO2 cryogenic bolometers and is currently in the last construction stage at the Gran Sasso National Laboratory (LNGS). Its primary goal is to observe neutrino-less double beta decay of 130Te, however thanks to the ultra-low background and large projected exposure it could also be suitable for other rare event searches, as the detection of solar axions, neutrinos from type II supernovae or direct detection of dark matter. The sensitivity for these searches will depend on the performance achieved at the low energy threshold. For this reason a trigger algorithm based on continuous data filtering has been developed which will allow lowering the threshold down to the few keV region. The new trigger has been tested in CUORE-0, a single-tower CUORE prototype consisting of 52 TeO2 bolometers and recently concluded, and here we present the results in terms of trigger efficiency, data selection and low-energy calibration.

  7. Threshold enhancement of diphoton resonances

    CERN Document Server

    Bharucha, Aoife; Goudelis, Andreas

    2016-10-10

    The data collected by the LHC collaborations at an energy of 13 TeV indicates the presence of an excess in the diphoton spectrum that would correspond to a resonance of a 750 GeV mass. The apparently large production cross section is nevertheless very difficult to explain in minimal models. We consider the possibility that the resonance is a pseudoscalar boson $A$ with a two--photon decay mediated by a charged and uncolored fermion having a mass at the $\\frac12 M_A$ threshold and a very small decay width, $\\ll 1$ MeV; one can then generate a large enhancement of the $A\\gamma\\gamma$ amplitude which explains the excess without invoking a large multiplicity of particles propagating in the loop, large electric charges and/or very strong Yukawa couplings. The implications of such a threshold enhancement are discussed in two explicit scenarios: i) the Minimal Supersymmetric Standard Model in which the $A$ state is produced via the top quark mediated gluon fusion process and decays into photons predominantly through...

  8. Use of auditory steady-state responses in children and comparison with other electrophysiological and behavioral tests.

    Science.gov (United States)

    François, M; Dehan, E; Carlevan, M; Dumont, H

    2016-11-01

    In patients who cannot or will not cooperate in behavioral hearing assessment, electrophysiological examinations are used, but are time-consuming because the subject has to remain immobile. The aim of this study was to assess whether auditory steady-state responses (ASSR) are sufficiently reliable, compared to auditory brainstem responses (ABR) and free-field audiometry, for assessment to begin with ASSR instead of ABR. A retrospective study was performed between January 2012 and April 2013, including children less than 6 years of age who could not be tested via headphones. ASSR and ABR were measured during natural sleep or under phenobarbital-alimemazine sedation. Subjective pure-tone audiometry was performed, using the visual reinforcement audiometry method, in 69 children who were able and willing to cooperate. A total of 175 children were included. ASSR and ABR thresholds showed good positive correlation (338 ears; Pearson's correlation coefficient, 0.87). Behavioral thresholds correlated significantly with ASSR thresholds (Student t-test for matched series; Phearing threshold rather than latency is to be determined. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  9. Auditory and tactile gap discrimination by observers with normal and impaired hearing.

    Science.gov (United States)

    Desloge, Joseph G; Reed, Charlotte M; Braida, Louis D; Perez, Zachary D; Delhorne, Lorraine A; Villabona, Timothy J

    2014-02-01

    Temporal processing ability for the senses of hearing and touch was examined through the measurement of gap-duration discrimination thresholds (GDDTs) employing the same low-frequency sinusoidal stimuli in both modalities. GDDTs were measured in three groups of observers (normal-hearing, hearing-impaired, and normal-hearing with simulated hearing loss) covering an age range of 21-69 yr. GDDTs for a baseline gap of 6 ms were measured for four different combinations of 100-ms leading and trailing markers (250-250, 250-400, 400-250, and 400-400 Hz). Auditory measurements were obtained for monaural presentation over headphones and tactile measurements were obtained using sinusoidal vibrations presented to the left middle finger. The auditory GDDTs of the hearing-impaired listeners, which were larger than those of the normal-hearing observers, were well-reproduced in the listeners with simulated loss. The magnitude of the GDDT was generally independent of modality and showed effects of age in both modalities. The use of different-frequency compared to same-frequency markers led to a greater deterioration in auditory GDDTs compared to tactile GDDTs and may reflect differences in bandwidth properties between the two sensory systems.

  10. Focal Suppression of Distractor Sounds by Selective Attention in Auditory Cortex.

    Science.gov (United States)

    Schwartz, Zachary P; David, Stephen V

    2018-01-01

    Auditory selective attention is required for parsing crowded acoustic environments, but cortical systems mediating the influence of behavioral state on auditory perception are not well characterized. Previous neurophysiological studies suggest that attention produces a general enhancement of neural responses to important target sounds versus irrelevant distractors. However, behavioral studies suggest that in the presence of masking noise, attention provides a focal suppression of distractors that compete with targets. Here, we compared effects of attention on cortical responses to masking versus non-masking distractors, controlling for effects of listening effort and general task engagement. We recorded single-unit activity from primary auditory cortex (A1) of ferrets during behavior and found that selective attention decreased responses to distractors masking targets in the same spectral band, compared with spectrally distinct distractors. This suppression enhanced neural target detection thresholds, suggesting that limited attention resources serve to focally suppress responses to distractors that interfere with target detection. Changing effort by manipulating target salience consistently modulated spontaneous but not evoked activity. Task engagement and changing effort tended to affect the same neurons, while attention affected an independent population, suggesting that distinct feedback circuits mediate effects of attention and effort in A1. © The Author 2017. Published by Oxford University Press.

  11. Sounds, behaviour, and auditory receptors of the armoured ground cricket, Acanthoplus longipes.

    Science.gov (United States)

    Kowalski, Kerstin; Lakes-Harlan, Reinhard

    2010-01-01

    The auditory sensory system of the taxon Hetrodinae has not been studied previously. Males of the African armoured ground cricket, Acanthoplus longipes (Orthoptera: Tettigoniidae: Hetrodinae) produce a calling song that lasts for minutes and consists of verses with two pulses. About three impulses are in the first pulse and about five impulses are in the second pulse. In contrast, the disturbance stridulation consists of verses with about 14 impulses that are not separated in pulses. Furthermore, the inter-impulse intervals of both types of sounds are different, whereas verses have similar durations. This indicates that the neuronal networks for sound generation are not identical. The frequency spectrum peaks at about 15 kHz in both types of sounds, whereas the hearing threshold has the greatest sensitivity between 4 and 10 kHz. The auditory afferents project into the prothoracic ganglion. The foreleg contains about 27 sensory neurons in the crista acustica; the midleg has 18 sensory neurons, and the hindleg has 14. The auditory system is similar to those of other Tettigoniidae.

  12. Metabolic changes in the auditory cortex in presbycusis demonstrated by MR spectroscopy.

    Science.gov (United States)

    Profant, Oliver; Balogová, Zuzana; Dezortová, Monika; Wagnerová, Dita; Hájek, Milan; Syka, Josef

    2013-08-01

    In humans, aging is accompanied by the deterioration of the hearing function--presbycusis. The major etiology for presbycusis is the loss of hair cells in the inner ear; less well known are changes in the central auditory system. Therefore, we used 1H magnetic resonance spectroscopy at 3T tomograph to examine metabolite levels in the auditory cortex of three groups of subjects: young healthy subjects less than 30 years old and subjects older than 65 years either with mild presbycusis corresponding to their age or with expressed presbycusis. Hearing function in all subjects was examined by pure tone audiometry (125-16,000 Hz). Significant differences were found in the concentrations of glutamate and N-acetylaspartate, with lower levels in aged subjects. Lactate was particularly increased in subjects with expressed presbycusis. Significant differences were not found in other metabolites, including GABA, between young and elderly subjects. The results demonstrate that the age-related changes of the inner ear are accompanied by a decrease in the excitatory neurotransmitter glutamate as well as a lactate increase in the auditory cortex that is more expressed in elderly subjects with large hearing threshold shifts. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Large cross-sectional study of presbycusis reveals rapid progressive decline in auditory temporal acuity.

    Science.gov (United States)

    Ozmeral, Erol J; Eddins, Ann C; Frisina, D Robert; Eddins, David A

    2016-07-01

    The auditory system relies on extraordinarily precise timing cues for the accurate perception of speech, music, and object identification. Epidemiological research has documented the age-related progressive decline in hearing sensitivity that is known to be a major health concern for the elderly. Although smaller investigations indicate that auditory temporal processing also declines with age, such measures have not been included in larger studies. Temporal gap detection thresholds (TGDTs; an index of auditory temporal resolution) measured in 1071 listeners (aged 18-98 years) were shown to decline at a minimum rate of 1.05 ms (15%) per decade. Age was a significant predictor of TGDT when controlling for audibility (partial correlation) and when restricting analyses to persons with normal-hearing sensitivity (n = 434). The TGDTs were significantly better for males (3.5 ms; 51%) than females when averaged across the life span. These results highlight the need for indices of temporal processing in diagnostics, as treatment targets, and as factors in models of aging. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. The effect of adaptation on the tuning curves of rat auditory cortex.

    Directory of Open Access Journals (Sweden)

    Mohsen Parto Dezfouli

    Full Text Available Repeated stimulus causes a specific suppression of neuronal responses, which is so-called as Stimulus-Specific Adaptation (SSA. This effect can be recovered when the stimulus changes. In the auditory system SSA is a well-known phenomenon that appears at different levels of the mammalian auditory pathway. In this study, we explored the effects of adaptation to a particular stimulus on the auditory tuning curves of anesthetized rats. We used two sequences and compared the responses of each tone combination in these two conditions. First sequence consists of different pure tone combinations that were presented randomly. In the second one, the same stimuli of the first sequence were presented in the context of an adapted stimulus (adapter that occupied 80% of sequence probability. The population results demonstrated that the adaptation factor decreased the frequency response area and made a change in the tuning curve to shift it unevenly toward the higher thresholds of tones. The local field potentials and multi-unit activity responses have indicated that the neural activities strength of the adapted frequency has been suppressed as well as with lower suppression in neighboring frequencies. This aforementioned reduction changed the characteristic frequency of the tuning curve.

  15. Auditory Spatial Discrimination and the Mismatch Negativity Response in Hearing-Impaired Individuals.

    Directory of Open Access Journals (Sweden)

    Yuexin Cai

    Full Text Available The aims of the present study were to investigate the ability of hearing-impaired (HI individuals with different binaural hearing conditions to discriminate spatial auditory-sources at the midline and lateral positions, and to explore the possible central processing mechanisms by measuring the minimal audible angle (MAA and mismatch negativity (MMN response. To measure MAA at the left/right 0°, 45° and 90° positions, 12 normal-hearing (NH participants and 36 patients with sensorineural hearing loss, which included 12 patients with symmetrical hearing loss (SHL and 24 patients with asymmetrical hearing loss (AHL [12 with unilateral hearing loss on the left (UHLL and 12 with unilateral hearing loss on the right (UHLR] were recruited. In addition, 128-electrode electroencephalography was used to record the MMN response in a separate group of 60 patients (20 UHLL, 20 UHLR and 20 SHL patients and 20 NH participants. The results showed MAA thresholds of the NH participants to be significantly lower than the HI participants. Also, a significantly smaller MAA threshold was obtained at the midline position than at the lateral position in both NH and SHL groups. However, in the AHL group, MAA threshold for the 90° position on the affected side was significantly smaller than the MMA thresholds obtained at other positions. Significantly reduced amplitudes and prolonged latencies of the MMN were found in the HI groups compared to the NH group. In addition, contralateral activation was found in the UHL group for sounds emanating from the 90° position on the affected side and in the NH group. These findings suggest that the abilities of spatial discrimination at the midline and lateral positions vary significantly in different hearing conditions. A reduced MMN amplitude and prolonged latency together with bilaterally symmetrical cortical activations over the auditory hemispheres indicate possible cortical compensatory changes associated with poor

  16. The tradeoff between signal detection and recognition rules auditory sensitivity under variable background noise conditions.

    Science.gov (United States)

    Lugli, Marco

    2015-12-07

    Animal acoustic communication commonly takes place under masked conditions. For instance, sound signals relevant for mating and survival are very often masked by background noise, which makes their detection and recognition by organisms difficult. Ambient noise (AN) varies in level and shape among different habitats, but also remarkable variations in time and space occurs within the same habitat. Variable AN conditions mask hearing thresholds of the receiver in complex and unpredictable ways, thereby causing distortions in sound perception. When communication takes place in a noisy environment, a highly sensitive system might confer no advantage to the receiver compared to a less sensitive one. The effects of noise masking on auditory thresholds and hearing-related functions are well known, and the potential role of AN in the evolution of the species' auditory sensitivity has been recognized by few authors. The mechanism of the underlying selection process has never been explored, however. Here I present a simple fitness model that seeks for the best sensitivity of a hearing system performing the detection and recognition of the sound under variable AN conditions. The model predicts higher sensitivity (i.e. lower hearing thresholds) as best strategy for species living in quiet habitats and lower sensitivity (i.e. higher hearing thresholds) as best strategy for those living in noisy habitats provided the cost of incorrect recognition is not low. The tradeoff between detection and recognition of acoustic signals appears to be a key factor determining the best level of hearing sensitivity of a species when acoustic communication is corrupted by noise. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Prolonged maturation of auditory perception and learning in gerbils.

    Science.gov (United States)

    Sarro, Emma C; Sanes, Dan H

    2010-08-01

    In humans, auditory perception reaches maturity over a broad age range, extending through adolescence. Despite this slow maturation, children are considered to be outstanding learners, suggesting that immature perceptual skills might actually be advantageous to improvement on an acoustic task as a result of training (perceptual learning). Previous non-human studies have not employed an identical task when comparing perceptual performance of young and mature subjects, making it difficult to assess learning. Here, we used an identical procedure on juvenile and adult gerbils to examine the perception of amplitude modulation (AM), a stimulus feature that is an important component of most natural sounds. On average, Adult animals could detect smaller fluctuations in amplitude (i.e., smaller modulation depths) than Juveniles, indicating immature perceptual skills in Juveniles. However, the population variance was much greater for Juveniles, a few animals displaying adult-like AM detection. To determine whether immature perceptual skills facilitated learning, we compared naïve performance on the AM detection task with the amount of improvement following additional training. The amount of improvement in Adults correlated with naïve performance: those with the poorest naïve performance improved the most. In contrast, the naïve performance of Juveniles did not predict the amount of learning. Those Juveniles with immature AM detection thresholds did not display greater learning than Adults. Furthermore, for several of the Juveniles with adult-like thresholds, AM detection deteriorated with repeated testing. Thus, immature perceptual skills in young animals were not associated with greater learning. (c) 2010 Wiley Periodicals, Inc.

  18. Auditory models of suprathreshold distortion and speech intelligibility in persons with impaired hearing.

    Science.gov (United States)

    Bernstein, Joshua G W; Summers, Van; Grassi, Elena; Grant, Ken W

    2013-04-01

    Hearing-impaired (HI) individuals with similar ages and audiograms often demonstrate substantial differences in speech-reception performance in noise. Traditional models of speech intelligibility focus primarily on average performance for a given audiogram, failing to account for differences between listeners with similar audiograms. Improved prediction accuracy might be achieved by simulating differences in the distortion that speech may undergo when processed through an impaired ear. Although some attempts to model particular suprathreshold distortions can explain general speech-reception deficits not accounted for by audibility limitations, little has been done to model suprathreshold distortion and predict speech-reception performance for individual HI listeners. Auditory-processing models incorporating individualized measures of auditory distortion, along with audiometric thresholds, could provide a more complete understanding of speech-reception deficits by HI individuals. A computational model capable of predicting individual differences in speech-recognition performance would be a valuable tool in the development and evaluation of hearing-aid signal-processing algorithms for enhancing speech intelligibility. This study investigated whether biologically inspired models simulating peripheral auditory processing for individual HI listeners produce more accurate predictions of speech-recognition performance than audiogram-based models. Psychophysical data on spectral and temporal acuity were incorporated into individualized auditory-processing models consisting of three stages: a peripheral stage, customized to reflect individual audiograms and spectral and temporal acuity; a cortical stage, which extracts spectral and temporal modulations relevant to speech; and an evaluation stage, which predicts speech-recognition performance by comparing the modulation content of clean and noisy speech. To investigate the impact of different aspects of peripheral processing

  19. Neurodynamics, tonality, and the auditory brainstem response.

    Science.gov (United States)

    Large, Edward W; Almonte, Felix V

    2012-04-01

    Tonal relationships are foundational in music, providing the basis upon which musical structures, such as melodies, are constructed and perceived. A recent dynamic theory of musical tonality predicts that networks of auditory neurons resonate nonlinearly to musical stimuli. Nonlinear resonance leads to stability and attraction relationships among neural frequencies, and these neural dynamics give rise to the perception of relationships among tones that we collectively refer to as tonal cognition. Because this model describes the dynamics of neural populations, it makes specific predictions about human auditory neurophysiology. Here, we show how predictions about the auditory brainstem response (ABR) are derived from the model. To illustrate, we derive a prediction about population responses to musical intervals that has been observed in the human brainstem. Our modeled ABR shows qualitative agreement with important features of the human ABR. This provides a source of evidence that fundamental principles of auditory neurodynamics might underlie the perception of tonal relationships, and forces reevaluation of the role of learning and enculturation in tonal cognition. © 2012 New York Academy of Sciences.

  20. Integration and segregation in auditory scene analysis

    Science.gov (United States)

    Sussman, Elyse S.

    2005-03-01

    Assessment of the neural correlates of auditory scene analysis, using an index of sound change detection that does not require the listener to attend to the sounds [a component of event-related brain potentials called the mismatch negativity (MMN)], has previously demonstrated that segregation processes can occur without attention focused on the sounds and that within-stream contextual factors influence how sound elements are integrated and represented in auditory memory. The current study investigated the relationship between the segregation and integration processes when they were called upon to function together. The pattern of MMN results showed that the integration of sound elements within a sound stream occurred after the segregation of sounds into independent streams and, further, that the individual streams were subject to contextual effects. These results are consistent with a view of auditory processing that suggests that the auditory scene is rapidly organized into distinct streams and the integration of sequential elements to perceptual units takes place on the already formed streams. This would allow for the flexibility required to identify changing within-stream sound patterns, needed to appreciate music or comprehend speech..

  1. Cancer of the external auditory canal

    DEFF Research Database (Denmark)

    Nyrop, Mette; Grøntved, Aksel

    2002-01-01

    OBJECTIVE: To evaluate the outcome of surgery for cancer of the external auditory canal and relate this to the Pittsburgh staging system used both on squamous cell carcinoma and non-squamous cell carcinoma. DESIGN: Retrospective case series of all patients who had surgery between 1979 and 2000. M...

  2. Diagnosing Dyslexia: The Screening of Auditory Laterality.

    Science.gov (United States)

    Johansen, Kjeld

    A study investigated whether a correlation exists between the degree and nature of left-brain laterality and specific reading and spelling difficulties. Subjects, 50 normal readers and 50 reading disabled persons native to the island of Bornholm, had their auditory laterality screened using pure-tone audiometry and dichotic listening. Results…

  3. Neural Entrainment to Auditory Imagery of Rhythms

    Directory of Open Access Journals (Sweden)

    Haruki Okawa

    2017-10-01

    Full Text Available A method of reconstructing perceived or imagined music by analyzing brain activity has not yet been established. As a first step toward developing such a method, we aimed to reconstruct the imagery of rhythm, which is one element of music. It has been reported that a periodic electroencephalogram (EEG response is elicited while a human imagines a binary or ternary meter on a musical beat. However, it is not clear whether or not brain activity synchronizes with fully imagined beat and meter without auditory stimuli. To investigate neural entrainment to imagined rhythm during auditory imagery of beat and meter, we recorded EEG while nine participants (eight males and one female imagined three types of rhythm without auditory stimuli but with visual timing, and then we analyzed the amplitude spectra of the EEG. We also recorded EEG while the participants only gazed at the visual timing as a control condition to confirm the visual effect. Furthermore, we derived features of the EEG using canonical correlation analysis (CCA and conducted an experiment to individually classify the three types of imagined rhythm from the EEG. The results showed that classification accuracies exceeded the chance level in all participants. These results suggest that auditory imagery of meter elicits a periodic EEG response that changes at the imagined beat and meter frequency even in the fully imagined conditions. This study represents the first step toward the realization of a method for reconstructing the imagined music from brain activity.

  4. Affective priming with auditory speech stimuli

    NARCIS (Netherlands)

    Degner, J.

    2011-01-01

    Four experiments explored the applicability of auditory stimulus presentation in affective priming tasks. In Experiment 1, it was found that standard affective priming effects occur when prime and target words are presented simultaneously via headphones similar to a dichotic listening procedure. In

  5. Auditory risk estimates for youth target shooting.

    Science.gov (United States)

    Meinke, Deanna K; Murphy, William J; Finan, Donald S; Lankford, James E; Flamme, Gregory A; Stewart, Michael; Soendergaard, Jacob; Jerome, Trevor W

    2014-03-01

    To characterize the impulse noise exposure and auditory risk for youth recreational firearm users engaged in outdoor target shooting events. The youth shooting positions are typically standing or sitting at a table, which places the firearm closer to the ground or reflective surface when compared to adult shooters. Acoustic characteristics were examined and the auditory risk estimates were evaluated using contemporary damage-risk criteria for unprotected adult listeners and the 120-dB peak limit suggested by the World Health Organization (1999) for children. Impulses were generated by 26 firearm/ammunition configurations representing rifles, shotguns, and pistols used by youth. Measurements were obtained relative to a youth shooter's left ear. All firearms generated peak levels that exceeded the 120 dB peak limit suggested by the WHO for children. In general, shooting from the seated position over a tabletop increases the peak levels, LAeq8 and reduces the unprotected maximum permissible exposures (MPEs) for both rifles and pistols. Pistols pose the greatest auditory risk when fired over a tabletop. Youth should utilize smaller caliber weapons, preferably from the standing position, and always wear hearing protection whenever engaging in shooting activities to reduce the risk for auditory damage.

  6. Auditory Neuropathy Spectrum Disorder: A Review

    Science.gov (United States)

    Norrix, Linda W.; Velenovsky, David S.

    2014-01-01

    Purpose: Auditory neuropathy spectrum disorder, or ANSD, can be a confusing diagnosis to physicians, clinicians, those diagnosed, and parents of children diagnosed with the condition. The purpose of this review is to provide the reader with an understanding of the disorder, the limitations in current tools to determine site(s) of lesion, and…

  7. Self-affirmation in auditory persuasion

    NARCIS (Netherlands)

    Elbert, Sarah; Dijkstra, Arie

    Persuasive health information can be presented through an auditory channel. Curiously enough, the effect of voice cues in health persuasion has hardly been studied. Research concerning visual persuasive messages showed that self-affirmation results in a more open-minded reaction to threatening

  8. Lateralization of auditory-cortex functions.

    Science.gov (United States)

    Tervaniemi, Mari; Hugdahl, Kenneth

    2003-12-01

    In the present review, we summarize the most recent findings and current views about the structural and functional basis of human brain lateralization in the auditory modality. Main emphasis is given to hemodynamic and electromagnetic data of healthy adult participants with regard to music- vs. speech-sound encoding. Moreover, a selective set of behavioral dichotic-listening (DL) results and clinical findings (e.g., schizophrenia, dyslexia) are included. It is shown that human brain has a strong predisposition to process speech sounds in the left and music sounds in the right auditory cortex in the temporal lobe. Up to great extent, an auditory area located at the posterior end of the temporal lobe (called planum temporale [PT]) underlies this functional asymmetry. However, the predisposition is not bound to informational sound content but to rapid temporal information more common in speech than in music sounds. Finally, we obtain evidence for the vulnerability of the functional specialization of sound processing. These altered forms of lateralization may be caused by top-down and bottom-up effects inter- and intraindividually In other words, relatively small changes in acoustic sound features or in their familiarity may modify the degree in which the left vs. right auditory areas contribute to sound encoding.

  9. Auditory object formation affects modulation perception

    DEFF Research Database (Denmark)

    Piechowiak, Tobias

    2005-01-01

    the target sound in time determine whether or not across-frequency modulation effects are observed. The results suggest that the binding of sound elements into coherent auditory objects precedes aspects of modulation analysis and imply a cortical locus involving integration times of several hundred...

  10. Auditory confrontation naming in Alzheimer's disease.

    Science.gov (United States)

    Brandt, Jason; Bakker, Arnold; Maroof, David Aaron

    2010-11-01

    Naming is a fundamental aspect of language and is virtually always assessed with visual confrontation tests. Tests of the ability to name objects by their characteristic sounds would be particularly useful in the assessment of visually impaired patients, and may be particularly sensitive in Alzheimer's disease (AD). We developed an auditory naming task, requiring the identification of the source of environmental sounds (i.e., animal calls, musical instruments, vehicles) and multiple-choice recognition of those not identified. In two separate studies mild-to-moderate AD patients performed more poorly than cognitively normal elderly on the auditory naming task. This task was also more difficult than two versions of a comparable visual naming task, and correlated more highly with Mini-Mental State Exam score. Internal consistency reliability was acceptable, although ROC analysis revealed auditory naming to be slightly less successful than visual confrontation naming in discriminating AD patients from normal participants. Nonetheless, our auditory naming task may prove useful in research and clinical practice, especially with visually impaired patients.

  11. Effects of Context on Auditory Stream Segregation

    Science.gov (United States)

    Snyder, Joel S.; Carter, Olivia L.; Lee, Suh-Kyung; Hannon, Erin E.; Alain, Claude

    2008-01-01

    The authors examined the effect of preceding context on auditory stream segregation. Low tones (A), high tones (B), and silences (-) were presented in an ABA-pattern. Participants indicated whether they perceived 1 or 2 streams of tones. The A tone frequency was fixed, and the B tone was the same as the A tone or had 1 of 3 higher frequencies.…

  12. The Goldilocks Effect in Infant Auditory Attention

    Science.gov (United States)

    Kidd, Celeste; Piantadosi, Steven T.; Aslin, Richard N.

    2014-01-01

    Infants must learn about many cognitive domains (e.g., language, music) from auditory statistics, yet capacity limits on their cognitive resources restrict the quantity that they can encode. Previous research has established that infants can attend to only a subset of available acoustic input. Yet few previous studies have directly examined infant…

  13. Auditory-motor coupling affects phonetic encoding.

    Science.gov (United States)

    Schmidt-Kassow, Maren; Thöne, Katharina; Kaiser, Jochen

    2017-11-27

    Recent studies have shown that moving in synchrony with auditory stimuli boosts attention allocation and verbal learning. Furthermore rhythmic tones are processed more efficiently than temporally random tones ('timing effect'), and this effect is increased when participants actively synchronize their motor performance with the rhythm of the tones, resulting in auditory-motor synchronization. Here, we investigated whether this applies also to sequences of linguistic stimuli (syllables). We compared temporally irregular syllable sequences with two temporally regular conditions where either the interval between syllable onsets (stimulus onset asynchrony, SOA) or the interval between the syllables' vowel onsets was kept constant. Entrainment to the stimulus presentation frequency (1 Hz) and event-related potentials were assessed in 24 adults who were instructed to detect pre-defined deviant syllables while they either pedaled or sat still on a stationary exercise bike. We found larger 1 Hz entrainment and P300 amplitudes for the SOA presentation during motor activity. Furthermore, the magnitude of the P300 component correlated with the motor variability in the SOA condition and 1 Hz entrainment, while in turn 1 Hz entrainment correlated with auditory-motor synchronization performance. These findings demonstrate that acute auditory-motor coupling facilitates phonetic encoding. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. fMRI of the auditory system: understanding the neural basis of auditory gestalt.

    Science.gov (United States)

    Di Salle, Francesco; Esposito, Fabrizio; Scarabino, Tommaso; Formisano, Elia; Marciano, Elio; Saulino, Claudio; Cirillo, Sossio; Elefante, Raffaele; Scheffler, Klaus; Seifritz, Erich

    2003-12-01

    Functional magnetic resonance imaging (fMRI) has rapidly become the most widely used imaging method for studying brain functions in humans. This is a result of its extreme flexibility of use and of the astonishingly detailed spatial and temporal information it provides. Nevertheless, until very recently, the study of the auditory system has progressed at a considerably slower pace compared to other functional systems. Several factors have limited fMRI research in the auditory field, including some intrinsic features of auditory functional anatomy and some peculiar interactions between fMRI technique and audition. A well known difficulty arises from the high intensity acoustic noise produced by gradient switching in echo-planar imaging (EPI), as well as in other fMRI sequences more similar to conventional MR sequences. The acoustic noise interacts in an unpredictable way with the experimental stimuli both from a perceptual point of view and in the evoked hemodynamics. To overcome this problem, different approaches have been proposed recently that generally require careful tailoring of the experimental design and the fMRI methodology to the specific requirements posed by the auditory research. The novel methodological approaches can make the fMRI exploration of auditory processing much easier and more reliable, and thus may permit filling the gap with other fields of neuroscience research. As a result, some fundamental neural underpinnings of audition are being clarified, and the way sound stimuli are integrated in the auditory gestalt are beginning to be understood.

  15. Biological impact of auditory expertise across the life span: musicians as a model of auditory learning

    Science.gov (United States)

    Strait, Dana L.; Kraus, Nina

    2013-01-01

    Experience-dependent characteristics of auditory function, especially with regard to speech-evoked auditory neurophysiology, have garnered increasing attention in recent years. This interest stems from both pragmatic and theoretical concerns as it bears implications for the prevention and remediation of language-based learning impairment in addition to providing insight into mechanisms engendering experience-dependent changes in human sensory function. Musicians provide an attractive model for studying the experience-dependency of auditory processing in humans due to their distinctive neural enhancements compared to nonmusicians. We have only recently begun to address whether these enhancements are observable early in life, during the initial years of music training when the auditory system is under rapid development, as well as later in life, after the onset of the aging process. Here we review neural enhancements in musically trained individuals across the life span in the context of cellular mechanisms that underlie learning, identified in animal models. Musicians’ subcortical physiologic enhancements are interpreted according to a cognitive framework for auditory learning, providing a model by which to study mechanisms of experience-dependent changes in auditory function in humans. PMID:23988583

  16. Auditory pathology in cri-du-chat (5p-) syndrome: phenotypic evidence for auditory neuropathy.

    Science.gov (United States)

    Swanepoel, D

    2007-10-01

    5p-(cri-du-chat syndrome) is a well-defined clinical entity presenting with phenotypic and cytogenetic variability. Despite recognition that abnormalities in audition are common, limited reports on auditory functioning in affected individuals are available. The current study presents a case illustrating the auditory functioning in a 22-month-old patient diagnosed with 5p- syndrome, karyotype 46,XX,del(5)(p13). Auditory neuropathy was diagnosed based on abnormal auditory evoked potentials with neural components suggesting severe to profound hearing loss in the presence of cochlear microphonic responses and behavioral reactions to sound at mild to moderate hearing levels. The current case and a review of available reports indicate that auditory neuropathy or neural dys-synchrony may be another phenotype of the condition possibly related to abnormal expression of the protein beta-catenin mapped to 5p. Implications are for routine and diagnostic specific assessments of auditory functioning and for employment of non-verbal communication methods in early intervention.

  17. Auditory Effects of Exposure to Noise and Solvents: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Lobato, Diolen Conceição Barros

    2014-01-01

    Full Text Available Introduction Industry workers are exposed to different environmental risk agents that, when combined, may potentiate risks to hearing. Objective To evaluate the effects of the combined exposure to noise and solvents on hearing in workers. Methods A transversal retrospective cohort study was performed through documentary analysis of an industry. The sample (n = 198 was divided into four groups: the noise group (NG, exposed only to noise; the noise and solvents group (NSG, exposed to noise and solvents; the noise control group and noise and solvents control group (CNS, no exposure. Results The NG showed 16.66% of cases suggestive of bilateral noise-induced hearing loss and NSG showed 5.26%. The NG and NSG had worse thresholds than their respective control groups. Females were less susceptible to noise than males; however, when simultaneously exposed to solvents, hearing was affected in a similar way, resulting in significant differences (p < 0.05. The 40- to 49-year-old age group was significantly worse (p < 0.05 in the auditory thresholds in the NSG compared with the CNS. Conclusion The results observed in this study indicate that simultaneous exposure to noise and solvents can damage the peripheral auditory system.

  18. Auditory effects of exposure to noise and solvents: a comparative study.

    Science.gov (United States)

    Lobato, Diolen Conceição Barros; Lacerda, Adriana Bender Moreira De; Gonçalves, Cláudia Giglio De Oliveira; Coifman, Herton

    2014-04-01

    Introduction Industry workers are exposed to different environmental risk agents that, when combined, may potentiate risks to hearing. Objective To evaluate the effects of the combined exposure to noise and solvents on hearing in workers. Methods A transversal retrospective cohort study was performed through documentary analysis of an industry. The sample (n = 198) was divided into four groups: the noise group (NG), exposed only to noise; the noise and solvents group (NSG), exposed to noise and solvents; the noise control group and noise and solvents control group (CNS), no exposure. Results The NG showed 16.66% of cases suggestive of bilateral noise-induced hearing loss and NSG showed 5.26%. The NG and NSG had worse thresholds than their respective control groups. Females were less susceptible to noise than males; however, when simultaneously exposed to solvents, hearing was affected in a similar way, resulting in significant differences (p old age group was significantly worse (p < 0.05) in the auditory thresholds in the NSG compared with the CNS. Conclusion The results observed in this study indicate that simultaneous exposure to noise and solvents can damage the peripheral auditory system.

  19. Instability Threshold “Hysteresis”

    Directory of Open Access Journals (Sweden)

    Agnes Muszynska

    1999-01-01

    Full Text Available The transient process which starts at the instability threshold of a rotor rotating in a fluid environment, and ends up in the limit cycle of self-excited vibrations known as fluid whirl or fluid whip, is discussed in this paper. A one-lateral-mode, isotropic, nonlinear model of the rotor with fluid interaction allows for exact particular solutions and an estimation of the transient process. The fluid interacting with the rotor is contained in a small radial clearance area, such as in bearings, seals, or rotor-to-stator clearances, and its effects are represented by fluid film radial stiffness, damping, and fluid inertia rotating at a different angular velocities.

  20. Epidemic thresholds for bipartite networks

    Science.gov (United States)

    Hernández, D. G.; Risau-Gusman, S.

    2013-11-01

    It is well known that sexually transmitted diseases (STD) spread across a network of human sexual contacts. This network is most often bipartite, as most STD are transmitted between men and women. Even though network models in epidemiology have quite a long history now, there are few general results about bipartite networks. One of them is the simple dependence, predicted using the mean field approximation, between the epidemic threshold and the average and variance of the degree distribution of the network. Here we show that going beyond this approximation can lead to qualitatively different results that are supported by numerical simulations. One of the new features, that can be relevant for applications, is the existence of a critical value for the infectivity of each population, below which no epidemics can arise, regardless of the value of the infectivity of the other population.

  1. High-resolution audiometry: an automated method for hearing threshold acquisition with quality control.

    Science.gov (United States)

    Bian, Lin

    2012-01-01

    In clinical practice, hearing thresholds are measured at only five to six frequencies at octave intervals. Thus, the audiometric configuration cannot closely reflect the actual status of the auditory structures. In addition, differential diagnosis requires quantitative comparison of behavioral thresholds with physiological measures, such as otoacoustic emissions (OAEs) that are usually measured in higher resolution. The purpose of this research was to develop a method to improve the frequency resolution of the audiogram. A repeated-measure design was used in the study to evaluate the reliability of the threshold measurements. A total of 16 participants with clinically normal hearing and mild hearing loss were recruited from a population of university students. No intervention was involved in the study. Custom developed system and software were used for threshold acquisition with quality control (QC). With real-ear calibration and monitoring of test signals, the system provided accurate and individualized measure of hearing thresholds that were determined by an analysis based on signal detection theory (SDT). The reliability of the threshold measure was assessed by correlation and differences between the repeated measures. The audiometric configurations were diverse and unique to each individual ear. The accuracy, within-subject reliability, and between-test repeatability are relatively high. With QC, the high-resolution audiograms can be reliably and accurately measured. Hearing thresholds measured as ear canal sound pressures with higher frequency resolution can provide more customized hearing-aid fitting. The test system may be integrated with other physiological measures, such as OAEs, into a comprehensive evaluative tool. American Academy of Audiology.

  2. Sesame allergy threshold dose distribution.

    Science.gov (United States)

    Dano, D; Remington, B C; Astier, C; Baumert, J L; Kruizinga, A G; Bihain, B E; Taylor, S L; Kanny, G

    2015-09-01

    Sesame is a relevant food allergen in France. Compared to other allergens there is a lack of food challenge data and more data could help sesame allergy risk management. The aim of this study is to collect more sesame challenge data and investigate the most efficient food challenge method for future studies. Records of patients at University Hospital in Nancy (France) with objective symptoms to sesame challenges were collected and combined with previously published data. An estimation of the sesame allergy population threshold was calculated based on individual NOAELs and LOAELs. Clinical dosing schemes at Nancy were investigated to see if the optimal protocol for sesame is currently used. Fourteen patients (10 M/4 F, 22 ± 14.85 years old) with objective symptoms were added to previously published data making a total of 35 sesame allergic patients. The most sensitive patient reacted to the first dose at challenge of 1.02 mg sesame protein. The ED05 ranges between 1.2 and 4.0 mg of sesame protein (Log-Normal, Log-Logistic, and Weibull models) and the ED10 between 4.2 and 6.2 mg. The optimal food challenge dosing scheme for sesame follows semi-log dose increases from 0.3 to 3000 mg protein. This article provides a valuable update to the existing clinical literature regarding sesame NOAELs and LOAELs. Establishment of a population threshold for sesame could help in increasing the credibility of precautionary labelling and decrease the costs associated with unexpected allergic reactions. Also, the use of an optimal dosing scheme would decrease time spent on diagnostic and thereafter on the economic burden of sesame allergy diagnosis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Multiple Mechanosensory Modalities Influence Development of Auditory Function

    Science.gov (United States)

    Horowitz, Seth S.; Tanyu, Leslie H.; Simmons, Andrea Megela

    2012-01-01

    Sensory development can be dependent on input from multiple modalities. During metamorphic development, ranid frogs exhibit rapid reorganization of pathways mediating auditory, vestibular, and lateral line modalities as the animal transforms from an aquatic to an amphibious form. Here we show that neural sensitivity to the underwater particle motion component of sound follows a different developmental trajectory than that of the pressure component. Throughout larval stages, cells in the medial vestibular nucleus show best frequencies to particle motion in the range from 15 to 65 Hz, with displacement thresholds of <10 μm. During metamorphic climax, best frequencies significantly increase, and sensitivity to lower-frequency (<25 Hz) stimuli tends to decline. These findings suggest that continued sensitivity to particle motion may compensate for the considerable loss of sensitivity to pressure waves observed during the developmental deaf period. Transport of a lipophilic dye from peripheral end organs to the dorsal medulla shows that fibers from the saccule in the inner ear and from the anterior lateral line both terminate in the medial vestibular nucleus. Saccular projections remain stable across larval development, whereas lateral line projections degenerate during metamorphic climax. Sensitivity to particle motion may be based on multimodal input early in development and on saccular input alone during the transition to amphibious life. PMID:17251417

  4. Functional properties of human auditory cortical fields

    Directory of Open Access Journals (Sweden)

    David L Woods

    2010-12-01

    Full Text Available While auditory cortex in non-human primates has been subdivided into multiple functionally-specialized auditory cortical fields (ACFs, the boundaries and functional specialization of human ACFs have not been defined. In the current study, we evaluated whether a widely accepted primate model of auditory cortex could explain regional tuning properties of fMRI activations on the cortical surface to attended and nonattended tones of different frequency, location, and intensity. The limits of auditory cortex were defined by voxels that showed significant activations to nonattended sounds. Three centrally-located fields with mirror-symmetric tonotopic organization were identified and assigned to the three core fields of the primate model while surrounding activations were assigned to belt fields following procedures similar to those used in macaque fMRI studies. The functional properties of core, medial belt, and lateral belt field groups were then analyzed. Field groups were distinguished by tonotopic organization, frequency selectivity, intensity sensitivity, contralaterality, binaural enhancement, attentional modulation, and hemispheric asymmetry. In general, core fields showed greater sensitivity to sound properties than did belt fields, while belt fields showed greater attentional modulation than core fields. Significant distinctions in intensity sensitivity and contralaterality were seen between adjacent core fields A1 and R, while multiple differences in tuning properties were evident at boundaries between adjacent core and belt fields. The reliable differences in functional properties between fields and field groups suggest that the basic primate pattern of auditory cortex organization is preserved in humans. A comparison of the sizes of functionally-defined ACFs in humans and macaques reveals a significant relative expansion in human lateral belt fields implicated in the processing of speech.

  5. Measuring Auditory Selective Attention using Frequency Tagging

    Directory of Open Access Journals (Sweden)

    Hari M Bharadwaj

    2014-02-01

    Full Text Available Frequency tagging of sensory inputs (presenting stimuli that fluctuate periodically at rates to which the cortex can phase lock has been used to study attentional modulation of neural responses to inputs in different sensory modalities. For visual inputs, the visual steady-state response (VSSR at the frequency modulating an attended object is enhanced, while the VSSR to a distracting object is suppressed. In contrast, the effect of attention on the auditory steady-state response (ASSR is inconsistent across studies. However, most auditory studies analyzed results at the sensor level or used only a small number of equivalent current dipoles to fit cortical responses. In addition, most studies of auditory spatial attention used dichotic stimuli (independent signals at the ears rather than more natural, binaural stimuli. Here, we asked whether these methodological choices help explain discrepant results. Listeners attended to one of two competing speech streams, one simulated from the left and one from the right, that were modulated at different frequencies. Using distributed source modeling of magnetoencephalography results, we estimate how spatially directed attention modulates the ASSR in neural regions across the whole brain. Attention enhances the ASSR power at the frequency of the attended stream in the contralateral auditory cortex. The attended-stream modulation frequency also drives phase-locked responses in the left (but not right precentral sulcus (lPCS, a region implicated in control of eye gaze and visual spatial attention. Importantly, this region shows no phase locking to the distracting stream suggesting that the lPCS in engaged in an attention-specific manner. Modeling results that take account of the geometry and phases of the cortical sources phase locked to the two streams (including hemispheric asymmetry of lPCS activity help partly explain why past ASSR studies of auditory spatial attention yield seemingly contradictory

  6. Articulatory movements modulate auditory responses to speech.

    Science.gov (United States)

    Agnew, Z K; McGettigan, C; Banks, B; Scott, S K

    2013-06-01

    Production of actions is highly dependent on concurrent sensory information. In speech production, for example, movement of the articulators is guided by both auditory and somatosensory input. It has been demonstrated in non-human primates that self-produced vocalizations and those of others are differentially processed in the temporal cortex. The aim of the current study was to investigate how auditory and motor responses differ for self-produced and externally produced speech. Using functional neuroimaging, subjects were asked to produce sentences aloud, to silently mouth while listening to a different speaker producing the same sentence, to passively listen to sentences being read aloud, or to read sentences silently. We show that that separate regions of the superior temporal cortex display distinct response profiles to speaking aloud, mouthing while listening, and passive listening. Responses in anterior superior temporal cortices in both hemispheres are greater for passive listening compared with both mouthing while listening, and speaking aloud. This is the first demonstration that articulation, whether or not it has auditory consequences, modulates responses of the dorsolateral temporal cortex. In contrast posterior regions of the superior temporal cortex are recruited during both articulation conditions. In dorsal regions of the posterior superior temporal gyrus, responses to mouthing and reading aloud were equivalent, and in more ventral posterior superior temporal sulcus, responses were greater for reading aloud compared with mouthing while listening. These data demonstrate an anterior-posterior division of superior temporal regions where anterior fields are suppressed during motor output, potentially for the purpose of enhanced detection of the speech of others. We suggest posterior fields are engaged in auditory processing for the guidance of articulation by auditory information. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. A controlled comparison of auditory steady-state responses and pure-tone audiometry in patients with hearing loss.

    Science.gov (United States)

    Wadhera, Raman; Hernot, Sharad; Gulati, Sat Paul; Kalra, Vijay

    2017-01-01

    We performed a prospective interventional study to evaluate correlations between hearing thresholds determined by pure-tone audiometry (PTA) and auditory steady-state response (ASSR) testing in two types of patients with hearing loss and a control group of persons with normal hearing. The study was conducted on 240 ears-80 ears with conductive hearing loss, 80 ears with sensorineural hearing loss, and 80 normal-hearing ears. We found that mean threshold differences between PTA results and ASSR testing at different frequencies did not exceed 15 dB in any group. Using Pearson correlation coefficient calculations, we determined that the two responses correlated better in patients with sensorineural hearing loss than in those with conductive hearing loss. We conclude that measuring ASSRs can be an excellent complement to other diagnostic methods in determining hearing thresholds.

  8. Characterization of auditory synaptic inputs to gerbil perirhinal cortex

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    Vibhakar C Kotak

    2015-08-01

    Full Text Available The representation of acoustic cues involves regions downstream from the auditory cortex (ACx. One such area, the perirhinal cortex (PRh, processes sensory signals containing mnemonic information. Therefore, our goal was to assess whether PRh receives auditory inputs from the auditory thalamus (MG and ACx in an auditory thalamocortical brain slice preparation and characterize these afferent-driven synaptic properties. When the MG or ACx was electrically stimulated, synaptic responses were recorded from the PRh neurons. Blockade of GABA-A receptors dramatically increased the amplitude of evoked excitatory potentials. Stimulation of the MG or ACx also evoked calcium transients in most PRh neurons. Separately, when fluoro ruby was injected in ACx in vivo, anterogradely labeled axons and terminals were observed in the PRh. Collectively, these data show that the PRh integrates auditory information from the MG and ACx and that auditory driven inhibition dominates the postsynaptic responses in a non-sensory cortical region downstream from the auditory cortex.

  9. Multisensory Interactions between Auditory and Haptic Object Recognition

    DEFF Research Database (Denmark)

    Kassuba, Tanja; Menz, Mareike M; R�der, Brigitte

    2013-01-01

    they matched a target object to a sample object within and across audition and touch. By introducing a delay between the presentation of sample and target stimuli, it was possible to dissociate haptic-to-auditory and auditory-to-haptic matching. We hypothesized that only semantically coherent auditory...... and haptic object features activate cortical regions that host unified conceptual object representations. The left fusiform gyrus (FG) and posterior superior temporal sulcus (pSTS) showed increased activation during crossmodal matching of semantically congruent but not incongruent object stimuli. In the FG......, this effect was found for haptic-to-auditory and auditory-to-haptic matching, whereas the pSTS only displayed a crossmodal matching effect for congruent auditory targets. Auditory and somatosensory association cortices showed increased activity during crossmodal object matching which was, however, independent...

  10. Nymphal development of the auditory system in the praying mantis Hierodula membranacea Burmeister (Dictyoptera, Mantidae).

    Science.gov (United States)

    Yager, D D

    1996-01-08

    Like other praying mantises, Hierodula membranacea has a single midline ear on the ventral surface of the metathorax. The ear comprises a deep groove with two tympana forming the walls. A tympanal organ on each side contains 30-40 scolopophorous sensillae with axons that terminate in the metathoracic ganglion in neuropil that does not match the auditory neuropil of other insects. Nymphal development of the mantis ear proceeds in three major stages: 1) The tympanal organ is completely formed with a full complement of sensillae before hatching; 2) the infolding and rotations that form the deep groove are completed primarily over the first half of nymphal development; and 3) over the last five instars (of ten), the tympana thicken and broaden to their adult size and shape, and the impedance-matching tracheal sacs also enlarge and move to become tightly apposed to the inner surfaces of the tympana. Auditory sensitivity gradually increases beginning with the fifth instar and closely parallels tympanum and tracheal sac growth. Late instar nymphs have auditory thresholds of 70-80 dB sound pressure level (SPL). Appropriate connections of afferents to a functional interneuronal system are clearly present by the eighth instar and possibly much earlier. The pattern of auditory system ontogeny in the mantis is similar to that in locusts and in noctuid moths, but it differs from crickets. In evolutionary terms, it is significant that the metathoracic anatomy of newly hatched mantis nymphs matches very closely the anatomy of the homologous regions in adult cockroaches, which are closely related to mantises but are without tympanal hearing, and in mantises that are thought to be primitively deaf.

  11. Auditory risk assessment of college music students in jazz band-based instructional activity.

    Science.gov (United States)

    Gopal, Kamakshi V; Chesky, Kris; Beschoner, Elizabeth A; Nelson, Paul D; Stewart, Bradley J

    2013-01-01

    It is well-known that musicians are at risk for music-induced hearing loss, however, systematic evaluation of music exposure and its effects on the auditory system are still difficult to assess. The purpose of the study was to determine if college students in jazz band-based instructional activity are exposed to loud classroom noise and consequently exhibit acute but significant changes in basic auditory measures compared to non-music students in regular classroom sessions. For this we (1) measured and compared personal exposure levels of college students (n = 14) participating in a routine 50 min jazz ensemble-based instructional activity (experimental) to personal exposure levels of non-music students (n = 11) participating in a 50-min regular classroom activity (control), and (2) measured and compared pre- to post-auditory changes associated with these two types of classroom exposures. Results showed that the L eq (equivalent continuous noise level) generated during the 50 min jazz ensemble-based instructional activity ranged from 95 dBA to 105.8 dBA with a mean of 99.5 ± 2.5 dBA. In the regular classroom, the L eq ranged from 46.4 dBA to 67.4 dBA with a mean of 49.9 ± 10.6 dBA. Additionally, significant differences were observed in pre to post-auditory measures between the two groups. The experimental group showed a significant temporary threshold shift bilaterally at 4000 Hz (P music students place them at risk for hearing loss compared to their non-music cohorts.

  12. Ubiquitous crossmodal Stochastic Resonance in humans: auditory noise facilitates tactile, visual and proprioceptive sensations.

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    Eduardo Lugo

    Full Text Available BACKGROUND: Stochastic resonance is a nonlinear phenomenon whereby the addition of noise can improve the detection of weak stimuli. An optimal amount of added noise results in the maximum enhancement, whereas further increases in noise intensity only degrade detection or information content. The phenomenon does not occur in linear systems, where the addition of noise to either the system or the stimulus only degrades the signal quality. Stochastic Resonance (SR has been extensively studied in different physical systems. It has been extended to human sensory systems where it can be classified as unimodal, central, behavioral and recently crossmodal. However what has not been explored is the extension of this crossmodal SR in humans. For instance, if under the same auditory noise conditions the crossmodal SR persists among different sensory systems. METHODOLOGY/PRINCIPAL FINDINGS: Using physiological and psychophysical techniques we demonstrate that the same auditory noise can enhance the sensitivity of tactile, visual and propioceptive system responses to weak signals. Specifically, we show that the effective auditory noise significantly increased tactile sensations of the finger, decreased luminance and contrast visual thresholds and significantly changed EMG recordings of the leg muscles during posture maintenance. CONCLUSIONS/SIGNIFICANCE: We conclude that crossmodal SR is a ubiquitous phenomenon in humans that can be interpreted within an energy and frequency model of multisensory neurons spontaneous activity. Initially the energy and frequency content of the multisensory neurons' activity (supplied by the weak signals is not enough to be detected but when the auditory noise enters the brain, it generates a general activation among multisensory neurons of different regions, modifying their original activity. The result is an integrated activation that promotes sensitivity transitions and the signals are then perceived. A physiologically

  13. NANOCI-Nanotechnology Based Cochlear Implant With Gapless Interface to Auditory Neurons.

    Science.gov (United States)

    Senn, Pascal; Roccio, Marta; Hahnewald, Stefan; Frick, Claudia; Kwiatkowska, Monika; Ishikawa, Masaaki; Bako, Peter; Li, Hao; Edin, Fredrik; Liu, Wei; Rask-Andersen, Helge; Pyykkö, Ilmari; Zou, Jing; Mannerström, Marika; Keppner, Herbert; Homsy, Alexandra; Laux, Edith; Llera, Miguel; Lellouche, Jean-Paul; Ostrovsky, Stella; Banin, Ehud; Gedanken, Aharon; Perkas, Nina; Wank, Ute; Wiesmüller, Karl-Heinz; Mistrík, Pavel; Benav, Heval; Garnham, Carolyn; Jolly, Claude; Gander, Filippo; Ulrich, Peter; Müller, Marcus; Löwenheim, Hubert

    2017-09-01

    : Cochlear implants (CI) restore functional hearing in the majority of deaf patients. Despite the tremendous success of these devices, some limitations remain. The bottleneck for optimal electrical stimulation with CI is caused by the anatomical gap between the electrode array and the auditory neurons in the inner ear. As a consequence, current devices are limited through 1) low frequency resolution, hence sub-optimal sound quality and 2), large stimulation currents, hence high energy consumption (responsible for significant battery costs and for impeding the development of fully implantable systems). A recently completed, multinational and interdisciplinary project called NANOCI aimed at overcoming current limitations by creating a gapless interface between auditory nerve fibers and the cochlear implant electrode array. This ambitious goal was achieved in vivo by neurotrophin-induced attraction of neurites through an intracochlear gel-nanomatrix onto a modified nanoCI electrode array located in the scala tympani of deafened guinea pigs. Functionally, the gapless interface led to lower stimulation thresholds and a larger dynamic range in vivo, and to reduced stimulation energy requirement (up to fivefold) in an in vitro model using auditory neurons cultured on multi-electrode arrays. In conclusion, the NANOCI project yielded proof of concept that a gapless interface between auditory neurons and cochlear implant electrode arrays is feasible. These findings may be of relevance for the development of future CI systems with better sound quality and performance and lower energy consumption. The present overview/review paper summarizes the NANOCI project history and highlights achievements of the individual work packages.

  14. Auditory inhibition of rapid eye movements and dream recall from REM sleep.

    Science.gov (United States)

    Stuart, Katrina; Conduit, Russell

    2009-03-01

    There is debate in dream research as to whether ponto-geniculo-occipital (PGO) waves or cortical arousal during sleep underlie the biological mechanisms of dreaming. This study comprised 2 experiments. As eye movements (EMs) are currently considered the best noninvasive indicator of PGO burst activity in humans, the aim of the first experiment was to investigate the effect of low-intensity repeated auditory stimulation on EMs (and inferred PGO burst activity) during REM sleep. It was predicted that such auditory stimuli during REM sleep would have a suppressive effect on EMs. The aim of the second experiment was to examine the effects of this auditory stimulation on subsequent dream reporting on awakening. Repeated measures design with counterbalanced order of experimental and control conditions across participants. Sleep laboratory based polysomnography (PSG) PARTICIPANTS: Experiment 1 : 5 males and 10 females aged 18-35 years (M = 20.8, SD = 5.4). Experiment 2 : 7 males and 13 females aged 18-35 years (M = 23.3, SD = 5.5). Below-waking threshold tone presentations during REM sleep compared to control REM sleep conditions without tone presentations. PSG records were manually scored for sleep stages, EEG arousals, and EMs. Auditory stimulation during REM sleep was related to: (a) an increase in EEG arousal, (b) a decrease in the amplitude and frequency of EMs, and (c) a decrease in the frequency of visual imagery reports on awakening. The results of this study provide phenomenological support for PGO-based theories of dream reporting on awakening from sleep in humans.

  15. Fast negative feedback enables mammalian auditory nerve fibers to encode a wide dynamic range of sound intensities.

    Directory of Open Access Journals (Sweden)

    Mark Ospeck

    Full Text Available Mammalian auditory nerve fibers (ANF are remarkable for being able to encode a 40 dB, or hundred fold, range of sound pressure levels into their firing rate. Most of the fibers are very sensitive and raise their quiescent spike rate by a small amount for a faint sound at auditory threshold. Then as the sound intensity is increased, they slowly increase their spike rate, with some fibers going up as high as ∼300 Hz. In this way mammals are able to combine sensitivity and wide dynamic range. They are also able to discern sounds embedded within background noise. ANF receive efferent feedback, which suggests that the fibers are readjusted according to the background noise in order to maximize the information content of their auditory spike trains. Inner hair cells activate currents in the unmyelinated distal dendrites of ANF where sound intensity is rate-coded into action potentials. We model this spike generator compartment as an attenuator that employs fast negative feedback. Input current induces rapid and proportional leak currents. This way ANF are able to have a linear frequency to input current (f-I curve that has a wide dynamic range. The ANF spike generator remains very sensitive to threshold currents, but efferent feedback is able to lower its gain in response to noise.

  16. BOLD responses to tactile stimuli in visual and auditory cortex depend on the frequency content of stimulation.

    Science.gov (United States)

    Nordmark, Per F; Pruszynski, J Andrew; Johansson, Roland S

    2012-10-01

    Although some brain areas preferentially process information from a particular sensory modality, these areas can also respond to other modalities. Here we used fMRI to show that such responsiveness to tactile stimuli depends on the temporal frequency of stimulation. Participants performed a tactile threshold-tracking task where the tip of either their left or right middle finger was stimulated at 3, 20, or 100 Hz. Whole-brain analysis revealed an effect of stimulus frequency in two regions: the auditory cortex and the visual cortex. The BOLD response in the auditory cortex was stronger during stimulation at hearable frequencies (20 and 100 Hz) whereas the response in the visual cortex was suppressed at infrasonic frequencies (3 Hz). Regardless of which hand was stimulated, the frequency-dependent effects were lateralized to the left auditory cortex and the right visual cortex. Furthermore, the frequency-dependent effects in both areas were abolished when the participants performed a visual task while receiving identical tactile stimulation as in the tactile threshold-tracking task. We interpret these findings in the context of the metamodal theory of brain function, which posits that brain areas contribute to sensory processing by performing specific computations regardless of input modality.

  17. Gap detection measured with electrically evoked auditory event-related potentials and speech-perception abilities in children with auditory neuropathy spectrum disorder.

    Science.gov (United States)

    He, Shuman; Grose, John H; Teagle, Holly F B; Woodard, Jennifer; Park, Lisa R; Hatch, Debora R; Buchman, Craig A

    2013-01-01

    This study aimed (1) to investigate the feasibility of recording the electrically evoked auditory event-related potential (eERP), including the onset P1-N1-P2 complex and the electrically evoked auditory change complex (EACC) in response to temporal gaps, in children with auditory neuropathy spectrum disorder (ANSD); and (2) to evaluate the relationship between these measures and speech-perception abilities in these subjects. Fifteen ANSD children who are Cochlear Nucleus device users participated in this study. For each subject, the speech-processor microphone was bypassed and the eERPs were elicited by direct stimulation of one mid-array electrode (electrode 12). The stimulus was a train of biphasic current pulses 800 msec in duration. Two basic stimulation conditions were used to elicit the eERP. In the no-gap condition, the entire pulse train was delivered uninterrupted to electrode 12, and the onset P1-N1-P2 complex was measured relative to the stimulus onset. In the gapped condition, the stimulus consisted of two pulse train bursts, each being 400 msec in duration, presented sequentially on the same electrode and separated by one of five gaps (i.e., 5, 10, 20, 50, and 100 msec). Open-set speech-perception ability of these subjects with ANSD was assessed using the phonetically balanced kindergarten (PBK) word lists presented at 60 dB SPL, using monitored live voice in a sound booth. The eERPs were recorded from all subjects with ANSD who participated in this study. There were no significant differences in test-retest reliability, root mean square amplitude or P1 latency for the onset P1-N1-P2 complex between subjects with good (>70% correct on PBK words) and poorer speech-perception performance. In general, the EACC showed less mature morphological characteristics than the onset P1-N1-P2 response recorded from the same subject. There was a robust correlation between the PBK word scores and the EACC thresholds for gap detection. Subjects with poorer speech

  18. Evaluation of auditory functions for Royal Canadian Mounted Police officers.

    Science.gov (United States)

    Vaillancourt, Véronique; Laroche, Chantal; Giguère, Christian; Beaulieu, Marc-André; Legault, Jean-Pierre

    2011-06-01

    Auditory fitness for duty (AFFD) testing is an important element in an assessment of workers' ability to perform job tasks safely and effectively. Functional hearing is particularly critical to job performance in law enforcement. Most often, assessment is based on pure-tone detection thresholds; however, its validity can be questioned and challenged in court. In an attempt to move beyond the pure-tone audiogram, some organizations like the Royal Canadian Mounted Police (RCMP) are incorporating additional testing to supplement audiometric data in their AFFD protocols, such as measurements of speech recognition in quiet and/or in noise, and sound localization. This article reports on the assessment of RCMP officers wearing hearing aids in speech recognition and sound localization tasks. The purpose was to quantify individual performance in different domains of hearing identified as necessary components of fitness for duty, and to document the type of hearing aids prescribed in the field and their benefit for functional hearing. The data are to help RCMP in making more informed decisions regarding AFFD in officers wearing hearing aids. The proposed new AFFD protocol included unaided and aided measures of speech recognition in quiet and in noise using the Hearing in Noise Test (HINT) and sound localization in the left/right (L/R) and front/back (F/B) horizontal planes. Sixty-four officers were identified and selected by the RCMP to take part in this study on the basis of hearing thresholds exceeding current audiometrically based criteria. This article reports the results of 57 officers wearing hearing aids. Based on individual results, 49% of officers were reclassified from nonoperational status to operational with limitations on fine hearing duties, given their unaided and/or aided performance. Group data revealed that hearing aids (1) improved speech recognition thresholds on the HINT, the effects being most prominent in Quiet and in conditions of spatial separation

  19. The relation between working memory capacity and auditory lateralization in children with auditory processing disorders.

    Science.gov (United States)

    Moossavi, Abdollah; Mehrkian, Saiedeh; Lotfi, Yones; Faghihzadeh, Soghrat; sajedi, Hamed

    2014-11-01

    Auditory processing disorder (APD) describes a complex and heterogeneous disorder characterized by poor speech perception, especially in noisy environments. APD may be responsible for a range of sensory processing deficits associated with learning difficulties. There is no general consensus about the nature of APD and how the disorder should be assessed or managed. This study assessed the effect of cognition abilities (working memory capacity) on sound lateralization in children with auditory processing disorders, in order to determine how "auditory cognition" interacts with APD. The participants in this cross-sectional comparative study were 20 typically developing and 17 children with a diagnosed auditory processing disorder (9-11 years old). Sound lateralization abilities investigated using inter-aural time (ITD) differences and inter-aural intensity (IID) differences with two stimuli (high pass and low pass noise) in nine perceived positions. Working memory capacity was evaluated using the non-word repetition, and forward and backward digits span tasks. Linear regression was employed to measure the degree of association between working memory capacity and localization tests between the two groups. Children in the APD group had consistently lower scores than typically developing subjects in lateralization and working memory capacity measures. The results showed working memory capacity had significantly negative correlation with ITD errors especially with high pass noise stimulus but not with IID errors in APD children. The study highlights the impact of working memory capacity on auditory lateralization. The finding of this research indicates that the extent to which working memory influences auditory processing depend on the type of auditory processing and the nature of stimulus/listening situation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  20. Cell-type specific short-term plasticity at auditory nerve synapses controls feed-forward inhibition in the dorsal cochlear nucleus.

    Science.gov (United States)

    Sedlacek, Miloslav; Brenowitz, Stephan D

    2014-01-01

    Feed-forward inhibition (FFI) represents a powerful mechanism by which control of the timing and fidelity of action potentials in local synaptic circuits of various brain regions is achieved. In the cochlear nucleus, the auditory nerve provides excitation to both principal neurons and inhibitory interneurons. Here, we investigated the synaptic circuit associated with fusiform cells (FCs), principal neurons of the dorsal cochlear nucleus (DCN) that receive excitation from auditory nerve fibers and inhibition from tuberculoventral cells (TVCs) on their basal dendrites in the deep layer of DCN. Despite the importance of these inputs in regulating fusiform cell firing behavior, the mechanisms determining the balance of excitation and FFI in this circuit are not well understood. Therefore, we examined the timing and plasticity of auditory nerve driven FFI onto FCs. We find that in some FCs, excitatory and inhibitory components of FFI had the same stimulation thresholds indicating they could be triggered by activation of the same fibers. In other FCs, excitation and inhibition exhibit different stimulus thresholds, suggesting FCs and TVCs might be activated by different sets of fibers. In addition, we find that during repetitive activation, synapses formed by the auditory nerve onto TVCs and FCs exhibit distinct modes of short-term plasticity. Feed-forward inhibitory post-synaptic currents (IPSCs) in FCs exhibit short-term depression because of prominent synaptic depression at the auditory nerve-TVC synapse. Depression of this feedforward inhibitory input causes a shift in the balance of fusiform cell synaptic input towards greater excitation and suggests that fusiform cell spike output will be enhanced by physiological patterns of auditory nerve activity.

  1. Cell-type specific short-term plasticity at auditory nerve synapses controls feed-forward inhibition in the dorsal cochlear nucleus

    Directory of Open Access Journals (Sweden)

    Miloslav eSedlacek

    2014-07-01

    Full Text Available Feedforward inhibition represents a powerful mechanism by which control of the timing and fidelity of action potentials in local synaptic circuits of various brain regions is achieved. In the cochlear nucleus, the auditory nerve provides excitation to both principal neurons and inhibitory interneurons. Here, we investigated the synaptic circuit associated with fusiform cells (FCs, principal neurons of the dorsal cochlear nucleus (DCN that receive excitation from auditory nerve fibers and inhibition from tuberculoventral cells (TVCs on their basal dendrites in the deep layer of DCN. Despite the importance of these inputs in regulating fusiform cell firing behavior, the mechanisms determining the balance of excitation and feed-forward inhibition in this circuit are not well understood. Therefore, we examined the timing and plasticity of auditory nerve driven feed-forward inhibition (FFI onto FCs. We find that in some FCs, excitatory and inhibitory components of feed-forward inhibition had the same stimulation thresholds indicating they could be triggered by activation of the same fibers. In other FCs, excitation and inhibition exhibit different stimulus thresholds, suggesting FCs and TVCs might be activated by different sets of fibers. In addition we find that during repetitive activation, synapses formed by the auditory nerve onto TVCs and FCs exhibit distinct modes of short-term plasticity. Feed-forward inhibitory post-synaptic currents (IPSCs in FCs exhibit short-term depression because of prominent synaptic depression at the auditory nerve-TVC synapse. Depression of this feedforward inhibitory input causes a shift in the balance of fusiform cell synaptic input towards greater excitation and suggests that fusiform cell spike output will be enhanced by physiological patterns of auditory nerve activity.

  2. Relationship between pure tone audiometry and tone burst auditory brainstem response at low frequencies gated with Blackman window.

    Science.gov (United States)

    Canale, Andrea; Dagna, Federico; Lacilla, Michelangelo; Piumetto, Elena; Albera, Roberto

    2012-03-01

    To assess the reliability of Blackman windowed tone burst auditory brainstem response (ABR) as a predictor of hearing threshold at low frequencies. Fifty-six subjects were divided in to three groups (normal hearing, conductive hearing loss, sensorineural hearing loss) after pure tone audiometry (PTA) testing. Then they underwent tone burst ABR using Blackman windowed stimuli at 0.5 kHz and 1 kHz. Results were compared with PTA threshold. Mean threshold differences between PTA and ABR ranged between 11 dB at 0.5 kHz and 14 dB at 1 kHz. ABR threshold was worse than PTA in each but 2 cases. Mean discrepancy between the two thresholds was about 20 dB in normal hearing, reducing in presence of hearing loss, without any differences in conductive and sensorineural cases. Tone burst ABR is a good predictor of hearing threshold at low frequencies, in case of suspected hearing loss. Further studies are recommended to evaluate an ipsilateral masking such as notched noise to ensure greater frequency specificity.

  3. Long-term recovery from hippocampal-related behavioral and biochemical abnormalities induced by noise exposure during brain development. Evaluation of auditory pathway integrity.

    Science.gov (United States)

    Uran, S L; Gómez-Casati, M E; Guelman, L R

    2014-10-01

    Sound is an important part of man's contact with the environment and has served as critical means for survival throughout his evolution. As a result of exposure to noise, physiological functions such as those involving structures of the auditory and non-auditory systems might be damaged. We have previously reported that noise-exposed developing rats elicited hippocampal-related histological, biochemical and behavioral changes. However, no data about the time lapse of these changes were reported. Moreover, measurements of auditory pathway function were not performed in exposed animals. Therefore, with the present work, we aim to test the onset and the persistence of the different extra-auditory abnormalities observed in noise-exposed rats and to evaluate auditory pathway integrity. Male Wistar rats of 15 days were exposed to moderate noise levels (95-97 dB SPL, 2 h a day) during one day (acute noise exposure, ANE) or during 15 days (sub-acute noise exposure, SANE). Hippocampal biochemical determinations as well as short (ST) and long term (LT) behavioral assessments were performed. In addition, histological and functional evaluations of the auditory pathway were carried out in exposed animals. Our results show that hippocampal-related behavioral and biochemical changes (impairments in habituation, recognition and associative memories as well as distortion of anxiety-related behavior, decreases in reactive oxygen species (ROS) levels and increases in antioxidant enzymes activities) induced by noise exposure were almost completely restored by PND 90. In addition, auditory evaluation shows that increased cochlear thresholds observed in exposed rats were re-established at PND 90, although with a remarkable supra-threshold amplitude reduction. These data suggest that noise-induced hippocampal and auditory-related alterations are mostly transient and that the effects of noise on the hippocampus might be, at least in part, mediated by the damage on the auditory pathway

  4. Enhancement of visual motion detection thresholds in early deaf people.

    Directory of Open Access Journals (Sweden)

    Martha M Shiell

    Full Text Available In deaf people, the auditory cortex can reorganize to support visual motion processing. Although this cross-modal reorganization has long been thought to subserve enhanced visual abilities, previous research has been unsuccessful at identifying behavioural enhancements specific to motion processing. Recently, research with congenitally deaf cats has uncovered an enhancement for visual motion detection. Our goal was to test for a similar difference between deaf and hearing people. We tested 16 early and profoundly deaf participants and 20 hearing controls. Participants completed a visual motion detection task, in which they were asked to determine which of two sinusoidal gratings was moving. The speed of the moving grating varied according to an adaptive staircase procedure, allowing us to determine the lowest speed necessary for participants to detect motion. Consistent with previous research in deaf cats, the deaf group had lower motion detection thresholds than the hearing. This finding supports the proposal that cross-modal reorganization after sensory deprivation will occur for supramodal sensory features and preserve the output functions.

  5. Context-dependent modulation of auditory processing by serotonin

    Science.gov (United States)

    Hurley, L.M.; Hall, I.C.

    2011-01-01

    Context-dependent plasticity in auditory processing is achieved in part by physiological mechanisms that link behavioral state to neural responses to sound. The neuromodulator serotonin has many characteristics suitable for such a role. Serotonergic neurons are extrinsic to the auditory system but send projections to most auditory regions. These projections release serotonin during particular behavioral contexts. Heightened levels of behavioral arousal and specific extrinsic events, including stressful or social events, increase serotonin availability in the auditory system. Although the release of serotonin is likely to be relatively diffuse, highly specific effects of serotonin on auditory neural circuitry are achieved through the localization of serotonergic projections, and through a large array of receptor types that are expressed by specific subsets of auditory neurons. Through this array, serotonin enacts plasticity in auditory processing in multiple ways. Serotonin changes the responses of auditory neurons to input through the alteration of intrinsic and synaptic properties, and alters both short- and long-term forms of plasticity. The infrastructure of the serotonergic system itself is also plastic, responding to age and cochlear trauma. These diverse findings support a view of serotonin as a widespread mechanism for behaviorally relevant plasticity in the regulation of auditory processing. This view also accommodates models of how the same regulatory mechanism can have pathological consequences for auditory processing. PMID:21187135

  6. A Survey of auditory display in image-guided interventions.

    Science.gov (United States)

    Black, David; Hansen, Christian; Nabavi, Arya; Kikinis, Ron; Hahn, Horst

    2017-03-08

    This article investigates the current state of the art of the use of auditory display in image-guided medical interventions. Auditory display is a means of conveying information using sound, and we review the use of this approach to support navigated interventions. We discuss the benefits and drawbacks of published systems and outline directions for future investigation. We undertook a review of scientific articles on the topic of auditory rendering in image-guided intervention. This includes methods for avoidance of risk structures and instrument placement and manipulation. The review did not include auditory display for status monitoring, for instance in anesthesia. We identified 15 publications in the course of the search. Most of the literature (60%) investigates the use of auditory display to convey distance of a tracked instrument to an object using proximity or safety margins. The remainder discuss continuous guidance for navigated instrument placement. Four of the articles present clinical evaluations, 11 present laboratory evaluations, and 3 present informal evaluation (2 present both laboratory and clinical evaluations). Auditory display is a growing field that has been largely neglected in research in image-guided intervention. Despite benefits of auditory displays reported in both the reviewed literature and non-medical fields, adoption in medicine has been slow. Future challenges include increasing interdisciplinary cooperation with auditory display investigators to develop more meaningful auditory display designs and comprehensive evaluations which target the benefits and drawbacks of auditory display in image guidance.

  7. Error Thresholds on Dynamic Fittness-Landscapes

    OpenAIRE

    Nilsson, Martin; Snoad, Nigel

    1999-01-01

    In this paper we investigate error-thresholds on dynamics fitness-landscapes. We show that there exists both lower and an upper threshold, representing limits to the copying fidelity of simple replicators. The lower bound can be expressed as a correction term to the error-threshold present on a static landscape. The upper error-threshold is a new limit that only exists on dynamic fitness-landscapes. We also show that for long genomes on highly dynamic fitness-landscapes there exists a lower b...

  8. Fuzzy-adaptive-thresholding-based exon prediction.

    Science.gov (United States)

    Agrawal, Ankit; Mittal, Ankush; Jain, Rahul; Takkar, Raghav

    2010-01-01

    Thresholding is always critical and decisive in many bioinformatics problems. In this paper, we propose and apply a fuzzy-logic-based adaptive thresholding approach to a well-known solution for the exon prediction problem, which uses a threshold on the frequency component at f = 1/3 in the nucleotide sequence. The proposed approach allows the thresholds to vary along the data set based on the local statistical properties. Experiments and results on the nucleotide data of Saccharomyces cerevisiae (Bakers yeast) illustrate the advantage of our approach. A user-friendly GUI in MATLAB is freely available for academic use at www.cs.iastate.edu/˜ankitag/FATBEP.html.

  9. Noise-Induced “Toughening” Effect in Wistar Rats: Enhanced Auditory Brainstem Responses Are Related to Calretinin and Nitric Oxide Synthase Upregulation

    Science.gov (United States)

    Alvarado, Juan C.; Fuentes-Santamaría, Verónica; Gabaldón-Ull, María C.; Jareño-Flores, Tania; Miller, Josef M.; Juiz, José M.

    2016-01-01

    An appropriate conditioning noise exposure may reduce a subsequent noise-induced threshold shift. Although this “toughening” effect helps to protect the auditory system from a subsequent traumatic noise exposure, the mechanisms that regulate this protective process are not fully understood yet. Accordingly, the goal of the present study was to characterize physiological processes associated with “toughening” and to determine their relationship to metabolic changes in the cochlea and cochlear nucleus (CN). Auditory brainstem responses (ABR) were evaluated in Wistar rats before and after exposures to a sound conditioning protocol consisting of a broad-band white noise of 118 dB SPL for 1 h every 72 h, four times. After the last ABR evaluation, animals were perfused and their cochleae and brains removed and processed for the activity markers calretinin (CR) and neuronal nitric oxide synthase (nNOS). Toughening was demonstrated by a progressively faster recovery of the threshold shift, as well as wave amplitudes and latencies over time. Immunostaining revealed an increase in CR and nNOS levels in the spiral ganglion, spiral ligament, and CN in noise-conditioned rats. Overall, these results suggest that the protective mechanisms of the auditory toughening effect initiate in the cochlea and extend to the central auditory system. Such phenomenon might be in part related to an interplay between CR and nitric oxide signaling pathways, and involve an increased cytosolic calcium buffering capacity induced by the noise conditioning protocol. PMID:27065815

  10. Shaping the aging brain: Role of auditory input patterns in the emergence of auditory cortical impairments

    Directory of Open Access Journals (Sweden)

    Brishna Soraya Kamal

    2013-09-01

    Full Text Available Age-related impairments in the primary auditory cortex (A1 include poor tuning selectivity, neural desynchronization and degraded responses to low-probability sounds. These changes have been largely attributed to reduced inhibition in the aged brain, and are thought to contribute to substantial hearing impairment in both humans and animals. Since many of these changes can be partially reversed with auditory training, it has been speculated that they might not be purely degenerative, but might rather represent negative plastic adjustments to noisy or distorted auditory signals reaching the brain. To test this hypothesis, we examined the impact of exposing young adult rats to 8 weeks of low-grade broadband noise on several aspects of A1 function and structure. We then characterized the same A1 elements in aging rats for comparison. We found that the impact of noise exposure on A1 tuning selectivity, temporal processing of auditory signal and responses to oddball tones was almost indistinguishable from the effect of natural aging. Moreover, noise exposure resulted in a reduction in the population of parvalbumin inhibitory interneurons and cortical myelin as previously documented in the aged group. Most of these changes reversed after returning the rats to a quiet environment. These results support the hypothesis that age-related changes in A1 have a strong activity-dependent component and indicate that the presence or absence of clear auditory input patterns might be a key factor in sustaining adult A1 function.

  11. Longitudinal auditory learning facilitates auditory cognition as revealed by microstate analysis.

    Science.gov (United States)

    Giroud, Nathalie; Lemke, Ulrike; Reich, Philip; Matthes, Katarina L; Meyer, Martin

    2017-02-01

    The current study investigates cognitive processes as reflected in late auditory-evoked potentials as a function of longitudinal auditory learning. A normal hearing adult sample (n=15) performed an active oddball task at three consecutive time points (TPs) arranged at two week intervals, and during which EEG was recorded. The stimuli comprised of syllables consisting of a natural fricative (/sh/,/s/,/f/) embedded between two /a/ sounds, as well as morphed transitions of the two syllables that served as deviants. Perceptual and cognitive modulations as reflected in the onset and the mean global field power (GFP) of N2b- and P3b-related microstates across four weeks were investigated. We found that the onset of P3b-like microstates, but not N2b-like microstates decreased across TPs, more strongly for difficult deviants leading to similar onsets for difficult and easy stimuli after repeated exposure. The mean GFP of all N2b-like and P3b-like microstates increased more in spectrally strong deviants compared to weak deviants, leading to a distinctive activation for each stimulus after learning. Our results indicate that longitudinal training of auditory-related cognitive mechanisms such as stimulus categorization, attention and memory updating processes are an indispensable part of successful auditory learning. This suggests that future studies should focus on the potential benefits of cognitive processes in auditory training. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Selective memory retrieval of auditory what and auditory where involves the ventrolateral prefrontal cortex

    Science.gov (United States)

    Kostopoulos, Penelope; Petrides, Michael

    2016-01-01

    There is evidence from the visual, verbal, and tactile memory domains that the midventrolateral prefrontal cortex plays a critical role in the top–down modulation of activity within posterior cortical areas for the selective retrieval of specific aspects of a memorized experience, a functional process often referred to as active controlled retrieval. In the present functional neuroimaging study, we explore the neural bases of active retrieval for auditory nonverbal information, about which almost nothing is known. Human participants were scanned with functional magnetic resonance imaging (fMRI) in a task in which they were presented with short melodies from different locations in a simulated virtual acoustic environment within the scanner and were then instructed to retrieve selectively either the particular melody presented or its location. There were significant activity increases specifically within the midventrolateral prefrontal region during the selective retrieval of nonverbal auditory information. During the selective retrieval of information from auditory memory, the right midventrolateral prefrontal region increased its interaction with the auditory temporal region and the inferior parietal lobule in the right hemisphere. These findings provide evidence that the midventrolateral prefrontal cortical region interacts with specific posterior cortical areas in the human cerebral cortex for the selective retrieval of object and location features of an auditory memory experience. PMID:26831102

  13. Pure word deafness. (Auditory verbal agnosia).

    Science.gov (United States)

    Shoumaker, R D; Ajax, E T; Schenkenberg, T

    1977-04-01

    The selective inability to comprehend the spoken word, in the absence of aphasia or defective or defective hearing, is defined as pure word deafness (auditory verbal agnosia). Reported cases of this rare disorder have suggested the site of involvement to be strategically placed, interrupting fibers from left and right primary auditory receptive areas which project to Wernicke's are in the dominant hemisphere. Our patient is a 44-year-old male who suffered from an uncertain illness complicated by fever, jaundice and generalized seizures seven years previously. Following an apparent convulsion, the patient was noted to be unable to understand spoken language without loss of ability to recognize and respond to sounds or marked impairment of speech or reading. The evidence suggested bilateral cerebral hemisphere disease more marked on the right. The abrupt onset without progression is consistent with a vascular or ischemic etiology. Conclusions about the nature of the lesion and areas involved must await further studies and ultimately tissue examination.

  14. Simulating Auditory Hallucinations in a Video Game

    DEFF Research Database (Denmark)

    Weinel, Jonathan; Cunningham, Stuart

    2017-01-01

    In previous work the authors have proposed the concept of 'ASC Simulations': including audio-visual installations and experiences, as well as interactive video game systems, which simulate altered states of consciousness (ASCs) such as dreams and hallucinations. Building on the discussion...... of the authors' previous paper, where a large-scale qualitative study explored the changes to auditory perception that users of various intoxicating substances report, here the authors present three prototype audio mechanisms for simulating hallucinations in a video game. These were designed in the Unity video...... game engine as an early proof-of-concept. The first mechanism simulates 'selective auditory attention' to different sound sources, by attenuating the amplitude of unattended sources. The second simulates 'enhanced sounds', by adjusting perceived brightness through filtering. The third simulates...

  15. Implicit temporal expectation attenuates auditory attentional blink.

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    Dawei Shen

    Full Text Available Attentional blink (AB describes a phenomenon whereby correct identification of a first target impairs the processing of a second target (i.e., probe nearby in time. Evidence suggests that explicit attention orienting in the time domain can attenuate the AB. Here, we used scalp-recorded, event-related potentials to examine whether auditory AB is also sensitive to implicit temporal attention orienting. Expectations were set up implicitly by varying the probability (i.e., 80% or 20% that the probe would occur at the +2 or +8 position following target presentation. Participants showed a significant AB, which was reduced with the increased probe probability at the +2 position. The probe probability effect was paralleled by an increase in P3b amplitude elicited by the probe. The results suggest that implicit temporal attention orienting can facilitate short-term consolidation of the probe and attenuate auditory AB.

  16. Binaural processing by the gecko auditory periphery

    DEFF Research Database (Denmark)

    Christensen-Dalsgaard, Jakob; Tang, Ye Zhong; Carr, Catherine E

    2011-01-01

    in the Tokay gecko with neurophysiological recordings from the auditory nerve. Laser vibrometry shows that their ear is a two-input system with approximately unity interaural transmission gain at the peak frequency (around 1.6 kHz). Median interaural delays are 260 μs, almost three times larger than predicted...... from gecko head size, suggesting interaural transmission may be boosted by resonances in the large, open mouth cavity (Vossen et al., 2010). Auditory nerve recordings are sensitive to both interaural time differences (ITD) and interaural level differences (ILD), reflecting the acoustical interactions......Lizards have highly directional ears, owing to strong acoustical coupling of the eardrums and almost perfect sound transmission from the contralateral ear. To investigate the neural processing of this remarkable tympanic directionality, we combined biophysical measurements of eardrum motion...

  17. Auditory environmental context affects visual distance perception.

    Science.gov (United States)

    Etchemendy, Pablo E; Abregú, Ezequiel; Calcagno, Esteban R; Eguia, Manuel C; Vechiatti, Nilda; Iasi, Federico; Vergara, Ramiro O

    2017-08-03

    In this article, we show that visual distance perception (VDP) is influenced by the auditory environmental context through reverberation-related cues. We performed two VDP experiments in two dark rooms with extremely different reverberation times: an anechoic chamber and a reverberant room. Subjects assigned to the reverberant room perceived the targets farther than subjects assigned to the anechoic chamber. Also, we found a positive correlation between the maximum perceived distance and the auditorily perceived room size. We next performed a second experiment in which the same subjects of Experiment 1 were interchanged between rooms. We found that subjects preserved the responses from the previous experiment provided they were compatible with the present perception of the environment; if not, perceived distance was biased towards the auditorily perceived boundaries of the room. Results of both experiments show that the auditory environment can influence VDP, presumably through reverberation cues related to the perception of room size.

  18. Anatomy and Physiology of the Auditory Tracts

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    Mohammad hosein Hekmat Ara

    1999-03-01

    Full Text Available Hearing is one of the excel sense of human being. Sound waves travel through the medium of air and enter the ear canal and then hit the tympanic membrane. Middle ear transfer almost 60-80% of this mechanical energy to the inner ear by means of “impedance matching”. Then, the sound energy changes to traveling wave and is transferred based on its specific frequency and stimulates organ of corti. Receptors in this organ and their synapses transform mechanical waves to the neural waves and transfer them to the brain. The central nervous system tract of conducting the auditory signals in the auditory cortex will be explained here briefly.

  19. Tinnitus and other auditory problems - occupational noise exposure below risk limits may cause inner ear dysfunction.

    Science.gov (United States)

    Lindblad, Ann-Cathrine; Rosenhall, Ulf; Olofsson, Åke; Hagerman, Björn

    2014-01-01

    The aim of the investigation was to study if dysfunctions associated to the cochlea or its regulatory system can be found, and possibly explain hearing problems in subjects with normal or near-normal audiograms. The design was a prospective study of subjects recruited from the general population. The included subjects were persons with auditory problems who had normal, or near-normal, pure tone hearing thresholds, who could be included in one of three subgroups: teachers, Education; people working with music, Music; and people with moderate or negligible noise exposure, Other. A fourth group included people with poorer pure tone hearing thresholds and a history of severe occupational noise, Industry. Ntotal = 193. The following hearing tests were used: - pure tone audiometry with Békésy technique, - transient evoked otoacoustic emissions and distortion product otoacoustic emissions, without and with contralateral noise; - psychoacoustical modulation transfer function, - forward masking, - speech recognition in noise, - tinnitus matching. A questionnaire about occupations, noise exposure, stress/anxiety, muscular problems, medication, and heredity, was addressed to the participants. Forward masking results were significantly worse for Education and Industry than for the other groups, possibly associated to the inner hair cell area. Forward masking results were significantly correlated to louder matched tinnitus. For many subjects speech recognition in noise, left ear, did not increase in a normal way when the listening level was increased. Subjects hypersensitive to loud sound had significantly better speech recognition in noise at the lower test level than subjects not hypersensitive. Self-reported stress/anxiety was similar for all groups. In conclusion, hearing dysfunctions were found in subjects with tinnitus and other auditory problems, combined with normal or near-normal pure tone thresholds. The teachers, mostly regarded as a group exposed to noise

  20. Tinnitus and other auditory problems - occupational noise exposure below risk limits may cause inner ear dysfunction.

    Directory of Open Access Journals (Sweden)

    Ann-Cathrine Lindblad

    Full Text Available The aim of the investigation was to study if dysfunctions associated to the cochlea or its regulatory system can be found, and possibly explain hearing problems in subjects with normal or near-normal audiograms. The design was a prospective study of subjects recruited from the general population. The included subjects were persons with auditory problems who had normal, or near-normal, pure tone hearing thresholds, who could be included in one of three subgroups: teachers, Education; people working with music, Music; and people with moderate or negligible noise exposure, Other. A fourth group included people with poorer pure tone hearing thresholds and a history of severe occupational noise, Industry. Ntotal = 193. The following hearing tests were used: - pure tone audiometry with Békésy technique, - transient evoked otoacoustic emissions and distortion product otoacoustic emissions, without and with contralateral noise; - psychoacoustical modulation transfer function, - forward masking, - speech recognition in noise, - tinnitus matching. A questionnaire about occupations, noise exposure, stress/anxiety, muscular problems, medication, and heredity, was addressed to the participants. Forward masking results were significantly worse for Education and Industry than for the other groups, possibly associated to the inner hair cell area. Forward masking results were significantly correlated to louder matched tinnitus. For many subjects speech recognition in noise, left ear, did not increase in a normal way when the listening level was increased. Subjects hypersensitive to loud sound had significantly better speech recognition in noise at the lower test level than subjects not hypersensitive. Self-reported stress/anxiety was similar for all groups. In conclusion, hearing dysfunctions were found in subjects with tinnitus and other auditory problems, combined with normal or near-normal pure tone thresholds. The teachers, mostly regarded as a group

  1. [Non-auditory effects of noise].

    Science.gov (United States)

    Albera, Roberto; Bin, Ilaria; Cena, Manuele; Dagna, Federico; Giordano, Pamela; Sammartano, Azia

    2011-01-01

    Non-auditory effects of noise involve several systems and functions, the most important of which are the cardiovascular, the vestibular and the psychic. Although several studies correlated noise exposure to some pathologies, like hypertension and anxiety disorders, and recent analysis carried out on cavy explained part of their pathophysiology, their multiple causes and the variability of individual reactions are still important limits to their classification.

  2. Sonic morphology: Aesthetic dimensional auditory spatial awareness

    Science.gov (United States)

    Whitehouse, Martha M.

    The sound and ceramic sculpture installation, " Skirting the Edge: Experiences in Sound & Form," is an integration of art and science demonstrating the concept of sonic morphology. "Sonic morphology" is herein defined as aesthetic three-dimensional auditory spatial awareness. The exhibition explicates my empirical phenomenal observations that sound has a three-dimensional form. Composed of ceramic sculptures that allude to different social and physical situations, coupled with sound compositions that enhance and create a three-dimensional auditory and visual aesthetic experience (see accompanying DVD), the exhibition supports the research question, "What is the relationship between sound and form?" Precisely how people aurally experience three-dimensional space involves an integration of spatial properties, auditory perception, individual history, and cultural mores. People also utilize environmental sound events as a guide in social situations and in remembering their personal history, as well as a guide in moving through space. Aesthetically, sound affects the fascination, meaning, and attention one has within a particular space. Sonic morphology brings art forms such as a movie, video, sound composition, and musical performance into the cognitive scope by generating meaning from the link between the visual and auditory senses. This research examined sonic morphology as an extension of musique concrete, sound as object, originating in Pierre Schaeffer's work in the 1940s. Pointing, as John Cage did, to the corporeal three-dimensional experience of "all sound," I composed works that took their total form only through the perceiver-participant's participation in the exhibition. While contemporary artist Alvin Lucier creates artworks that draw attention to making sound visible, "Skirting the Edge" engages the perceiver-participant visually and aurally, leading to recognition of sonic morphology.

  3. Neural correlates of auditory scale illusion.

    Science.gov (United States)

    Kuriki, Shinya; Numao, Ryousuke; Nemoto, Iku

    2016-09-01

    The auditory illusory perception "scale illusion" occurs when ascending and descending musical scale tones are delivered in a dichotic manner, such that the higher or lower tone at each instant is presented alternately to the right and left ears. Resulting tone sequences have a zigzag pitch in one ear and the reversed (zagzig) pitch in the other ear. Most listeners hear illusory smooth pitch sequences of up-down and down-up streams in the two ears separated in higher and lower halves of the scale. Although many behavioral studies have been conducted, how and where in the brain the illusory percept is formed have not been elucidated. In this study, we conducted functional magnetic resonance imaging using sequential tones that induced scale illusion (ILL) and those that mimicked the percept of scale illusion (PCP), and we compared the activation responses evoked by those stimuli by region-of-interest analysis. We examined the effects of adaptation, i.e., the attenuation of response that occurs when close-frequency sounds are repeated, which might interfere with the changes in activation by the illusion process. Results of the activation difference of the two stimuli, measured at varied tempi of tone presentation, in the superior temporal auditory cortex were not explained by adaptation. Instead, excess activation of the ILL stimulus from the PCP stimulus at moderate tempi (83 and 126 bpm) was significant in the posterior auditory cortex with rightward superiority, while significant prefrontal activation was dominant at the highest tempo (245 bpm). We suggest that the area of the planum temporale posterior to the primary auditory cortex is mainly involved in the illusion formation, and that the illusion-related process is strongly dependent on the rate of tone presentation. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Lesions in the external auditory canal

    Directory of Open Access Journals (Sweden)

    Priyank S Chatra

    2011-01-01

    Full Text Available The external auditory canal is an S- shaped osseo-cartilaginous structure that extends from the auricle to the tympanic membrane. Congenital, inflammatory, neoplastic, and traumatic lesions can affect the EAC. High-resolution CT is well suited for the evaluation of the temporal bone, which has a complex anatomy with multiple small structures. In this study, we describe the various lesions affecting the EAC.

  5. Stroke caused auditory attention deficits in children

    Directory of Open Access Journals (Sweden)

    Karla Maria Ibraim da Freiria Elias

    2013-01-01

    Full Text Available OBJECTIVE: To verify the auditory selective attention in children with stroke. METHODS: Dichotic tests of binaural separation (non-verbal and consonant-vowel and binaural integration - digits and Staggered Spondaic Words Test (SSW - were applied in 13 children (7 boys, from 7 to 16 years, with unilateral stroke confirmed by neurological examination and neuroimaging. RESULTS: The attention performance showed significant differences in comparison to the control group in both kinds of tests. In the non-verbal test, identifications the ear opposite the lesion in the free recall stage was diminished and, in the following stages, a difficulty in directing attention was detected. In the consonant- vowel test, a modification in perceptual asymmetry and difficulty in focusing in the attended stages was found. In the digits and SSW tests, ipsilateral, contralateral and bilateral deficits were detected, depending on the characteristics of the lesions and demand of the task. CONCLUSION: Stroke caused auditory attention deficits when dealing with simultaneous sources of auditory information.

  6. BALDEY: A database of auditory lexical decisions.

    Science.gov (United States)

    Ernestus, Mirjam; Cutler, Anne

    2015-01-01

    In an auditory lexical decision experiment, 5541 spoken content words and pseudowords were presented to 20 native speakers of Dutch. The words vary in phonological make-up and in number of syllables and stress pattern, and are further representative of the native Dutch vocabulary in that most are morphologically complex, comprising two stems or one stem plus derivational and inflectional suffixes, with inflections representing both regular and irregular paradigms; the pseudowords were matched in these respects to the real words. The BALDEY ("biggest auditory lexical decision experiment yet") data file includes response times and accuracy rates, with for each item morphological information plus phonological and acoustic information derived from automatic phonemic segmentation of the stimuli. Two initial analyses illustrate how this data set can be used. First, we discuss several measures of the point at which a word has no further neighbours and compare the degree to which each measure predicts our lexical decision response outcomes. Second, we investigate how well four different measures of frequency of occurrence (from written corpora, spoken corpora, subtitles, and frequency ratings by 75 participants) predict the same outcomes. These analyses motivate general conclusions about the auditory lexical decision task. The (publicly available) BALDEY database lends itself to many further analyses.

  7. Visual speech gestures modulate efferent auditory system.

    Science.gov (United States)

    Namasivayam, Aravind Kumar; Wong, Wing Yiu Stephanie; Sharma, Dinaay; van Lieshout, Pascal

    2015-03-01

    Visual and auditory systems interact at both cortical and subcortical levels. Studies suggest a highly context-specific cross-modal modulation of the auditory system by the visual system. The present study builds on this work by sampling data from 17 young healthy adults to test whether visual speech stimuli evoke different responses in the auditory efferent system compared to visual non-speech stimuli. The descending cortical influences on medial olivocochlear (MOC) activity were indirectly assessed by examining the effects of contralateral suppression of transient-evoked otoacoustic emissions (TEOAEs) at 1, 2, 3 and 4 kHz under three conditions: (a) in the absence of any contralateral noise (Baseline), (b) contralateral noise + observing facial speech gestures related to productions of vowels /a/ and /u/ and (c) contralateral noise + observing facial non-speech gestures related to smiling and frowning. The results are based on 7 individuals whose data met strict recording criteria and indicated a significant difference in TEOAE suppression between observing speech gestures relative to the non-speech gestures, but only at the 1 kHz frequency. These results suggest that observing a speech gesture compared to a non-speech gesture may trigger a difference in MOC activity, possibly to enhance peripheral neural encoding. If such findings can be reproduced in future research, sensory perception models and theories positing the downstream convergence of unisensory streams of information in the cortex may need to be revised.

  8. Mechanisms of auditory verbal hallucination in schizophrenia

    Directory of Open Access Journals (Sweden)

    Raymond eCho

    2013-11-01

    Full Text Available Recent work on the mechanisms underlying auditory verbal hallucination (AVH has been heavily informed by self-monitoring accounts that postulate defects in an internal monitoring mechanism as the basis of AVH. A more neglected alternative is an account focusing on defects in auditory processing, namely a spontaneous activation account of auditory activity underlying AVH. Science is often aided by putting theories in competition. Accordingly, a discussion that systematically contrasts the two models of AVH can generate sharper questions that will lead to new avenues of investigation. In this paper, we provide such a theoretical discussion of the two models, drawing strong contrasts between them. We identify a set of challenges for the self-monitoring account and argue that the spontaneous activation account has much in favor of it and should be the default account. Our theoretical overview leads to new questions and issues regarding the explanation of AVH as a subjective phenomenon and its neural basis. Accordingly, we suggest a set of experimental strategies to dissect the underlying mechanisms of AVH in light of the two competing models.

  9. Hierarchical processing of auditory objects in humans.

    Directory of Open Access Journals (Sweden)

    Sukhbinder Kumar

    2007-06-01

    Full Text Available This work examines the computational architecture used by the brain during the analysis of the spectral envelope of sounds, an important acoustic feature for defining auditory objects. Dynamic causal modelling and Bayesian model selection were used to evaluate a family of 16 network models explaining functional magnetic resonance imaging responses in the right temporal lobe during spectral envelope analysis. The models encode different hypotheses about the effective connectivity between Heschl's Gyrus (HG, containing the primary auditory cortex, planum temporale (PT, and superior temporal sulcus (STS, and the modulation of that coupling during spectral envelope analysis. In particular, we aimed to determine whether information processing during spectral envelope analysis takes place in a serial or parallel fashion. The analysis provides strong support for a serial architecture with connections from HG to PT and from PT to STS and an increase of the HG to PT connection during spectral envelope analysis. The work supports a computational model of auditory object processing, based on the abstraction of spectro-temporal "templates" in the PT before further analysis of the abstracted form in anterior temporal lobe areas.

  10. Binaural processing by the gecko auditory periphery.

    Science.gov (United States)

    Christensen-Dalsgaard, Jakob; Tang, Yezhong; Carr, Catherine E

    2011-05-01

    Lizards have highly directional ears, owing to strong acoustical coupling of the eardrums and almost perfect sound transmission from the contralateral ear. To investigate the neural processing of this remarkable tympanic directionality, we combined biophysical measurements of eardrum motion in the Tokay gecko with neurophysiological recordings from the auditory nerve. Laser vibrometry shows that their ear is a two-input system with approximately unity interaural transmission gain at the peak frequency (∼ 1.6 kHz). Median interaural delays are 260 μs, almost three times larger than predicted from gecko head size, suggesting interaural transmission may be boosted by resonances in the large, open mouth cavity (Vossen et al. 2010). Auditory nerve recordings are sensitive to both interaural time differences (ITD) and interaural level differences (ILD), reflecting the acoustical interactions of direct and indirect sound components at the eardrum. Best ITD and click delays match interaural transmission delays, with a range of 200-500 μs. Inserting a mold in the mouth cavity blocks ITD and ILD sensitivity. Thus the neural response accurately reflects tympanic directionality, and most neurons in the auditory pathway should be directional.

  11. Sensorimotor Learning Enhances Expectations During Auditory Perception.

    Science.gov (United States)

    Mathias, Brian; Palmer, Caroline; Perrin, Fabien; Tillmann, Barbara

    2015-08-01

    Sounds that have been produced with one's own motor system tend to be remembered better than sounds that have only been perceived, suggesting a role of motor information in memory for auditory stimuli. To address potential contributions of the motor network to the recognition of previously produced sounds, we used event-related potential, electric current density, and behavioral measures to investigate memory for produced and perceived melodies. Musicians performed or listened to novel melodies, and then heard the melodies either in their original version or with single pitch alterations. Production learning enhanced subsequent recognition accuracy and increased amplitudes of N200, P300, and N400 responses to pitch alterations. Premotor and supplementary motor regions showed greater current density during the initial detection of alterations in previously produced melodies than in previously perceived melodies, associated with the N200. Primary motor cortex was more strongly engaged by alterations in previously produced melodies within the P300 and N400 timeframes. Motor memory traces may therefore interface with auditory pitch percepts in premotor regions as early as 200 ms following perceived pitch onsets. Outcomes suggest that auditory-motor interactions contribute to memory benefits conferred by production experience, and support a role of motor prediction mechanisms in the production effect. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  12. Auditory Discrimination Learning: Role of Working Memory.

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    Yu-Xuan Zhang

    Full Text Available Perceptual training is generally assumed to improve perception by modifying the encoding or decoding of sensory information. However, this assumption is incompatible with recent demonstrations that transfer of learning can be enhanced by across-trial variation of training stimuli or task. Here we present three lines of evidence from healthy adults in support of the idea that the enhanced transfer of auditory discrimination learning is mediated by working memory (WM. First, the ability to discriminate small differences in tone frequency or duration was correlated with WM measured with a tone n-back task. Second, training frequency discrimination around a variable frequency transferred to and from WM learning, but training around a fixed frequency did not. The transfer of learning in both directions was correlated with a reduction of the influence of stimulus variation in the discrimination task, linking WM and its improvement to across-trial stimulus interaction in auditory discrimination. Third, while WM training transferred broadly to other WM and auditory discrimination tasks, variable-frequency training on duration discrimination did not improve WM, indicating that stimulus variation challenges and trains WM only if the task demands stimulus updating in the varied dimension. The results provide empirical evidence as well as a theoretic framework for interactions between cognitive and sensory plasticity during perceptual experience.

  13. Central auditory masking by an illusory tone.

    Science.gov (United States)

    Plack, Christopher J; Oxenham, Andrew J; Kreft, Heather A; Carlyon, Robert P

    2013-01-01

    Many natural sounds fluctuate over time. The detectability of sounds in a sequence can be reduced by prior stimulation in a process known as forward masking. Forward masking is thought to reflect neural adaptation or neural persistence in the auditory nervous system, but it has been unclear where in the auditory pathway this processing occurs. To address this issue, the present study used a "Huggins pitch" stimulus, the perceptual effects of which depend on central auditory processing. Huggins pitch is an illusory tonal sensation produced when the same noise is presented to the two ears except for a narrow frequency band that is different (decorrelated) between the ears. The pitch sensation depends on the combination of the inputs to the two ears, a process that first occurs at the level of the superior olivary complex in the brainstem. Here it is shown that a Huggins pitch stimulus produces more forward masking in the frequency region of the decorrelation than a noise stimulus identical to the Huggins-pitch stimulus except with perfect correlation between the ears. This stimulus has a peripheral neural representation that is identical to that of the Huggins-pitch stimulus. The results show that processing in, or central to, the superior olivary complex can contribute to forward masking in human listeners.

  14. Central auditory masking by an illusory tone.

    Directory of Open Access Journals (Sweden)

    Christopher J Plack

    Full Text Available Many natural sounds fluctuate over time. The detectability of sounds in a sequence can be reduced by prior stimulation in a process known as forward masking. Forward masking is thought to reflect neural adaptation or neural persistence in the auditory nervous system, but it has been unclear where in the auditory pathway this processing occurs. To address this issue, the present study used a "Huggins pitch" stimulus, the perceptual effects of which depend on central auditory processing. Huggins pitch is an illusory tonal sensation produced when the same noise is presented to the two ears except for a narrow frequency band that is different (decorrelated between the ears. The pitch sensation depends on the combination of the inputs to the two ears, a process that first occurs at the level of the superior olivary complex in the brainstem. Here it is shown that a Huggins pitch stimulus produces more forward masking in the frequency region of the decorrelation than a noise stimulus identical to the Huggins-pitch stimulus except with perfect correlation between the ears. This stimulus has a peripheral neural representation that is identical to that of the Huggins-pitch stimulus. The results show that processing in, or central to, the superior olivary complex can contribute to forward masking in human listeners.

  15. Binaural processing by the gecko auditory periphery

    Science.gov (United States)

    Christensen-Dalsgaard, Jakob; Tang, Yezhong

    2011-01-01

    Lizards have highly directional ears, owing to strong acoustical coupling of the eardrums and almost perfect sound transmission from the contralateral ear. To investigate the neural processing of this remarkable tympanic directionality, we combined biophysical measurements of eardrum motion in the Tokay gecko with neurophysiological recordings from the auditory nerve. Laser vibrometry shows that their ear is a two-input system with approximately unity interaural transmission gain at the peak frequency (∼1.6 kHz). Median interaural delays are 260 μs, almost three times larger than predicted from gecko head size, suggesting interaural transmission may be boosted by resonances in the large, open mouth cavity (Vossen et al. 2010). Auditory nerve recordings are sensitive to both interaural time differences (ITD) and interaural level differences (ILD), reflecting the acoustical interactions of direct and indirect sound components at the eardrum. Best ITD and click delays match interaural transmission delays, with a range of 200–500 μs. Inserting a mold in the mouth cavity blocks ITD and ILD sensitivity. Thus the neural response accurately reflects tympanic directionality, and most neurons in the auditory pathway should be directional. PMID:21325679

  16. Sleep and rest facilitate auditory learning.

    Science.gov (United States)

    Gottselig, J M; Hofer-Tinguely, G; Borbély, A A; Regel, S J; Landolt, H-P; Rétey, J V; Achermann, P

    2004-01-01

    Sleep is superior to waking for promoting performance improvements between sessions of visual perceptual and motor learning tasks. Few studies have investigated possible effects of sleep on auditory learning. A key issue is whether sleep specifically promotes learning, or whether restful waking yields similar benefits. According to the "interference hypothesis," sleep facilitates learning because it prevents interference from ongoing sensory input, learning and other cognitive activities that normally occur during waking. We tested this hypothesis by comparing effects of sleep, busy waking (watching a film) and restful waking (lying in the dark) on auditory tone sequence learning. Consistent with recent findings for human language learning, we found that compared with busy waking, sleep between sessions of auditory tone sequence learning enhanced performance improvements. Restful waking provided similar benefits, as predicted based on the interference hypothesis. These findings indicate that physiological, behavioral and environmental conditions that accompany restful waking are sufficient to facilitate learning and may contribute to the facilitation of learning that occurs during sleep.

  17. Auditory perception of a human walker.

    Science.gov (United States)

    Cottrell, David; Campbell, Megan E J

    2014-01-01

    When one hears footsteps in the hall, one is able to instantly recognise it as a person: this is an everyday example of auditory biological motion perception. Despite the familiarity of this experience, research into this phenomenon is in its infancy compared with visual biological motion perception. Here, two experiments explored sensitivity to, and recognition of, auditory stimuli of biological and nonbiological origin. We hypothesised that the cadence of a walker gives rise to a temporal pattern of impact sounds that facilitates the recognition of human motion from auditory stimuli alone. First a series of detection tasks compared sensitivity with three carefully matched impact sounds: footsteps, a ball bouncing, and drumbeats. Unexpectedly, participants were no more sensitive to footsteps than to impact sounds of nonbiological origin. In the second experiment participants made discriminations between pairs of the same stimuli, in a series of recognition tasks in which the temporal pattern of impact sounds was manipulated to be either that of a walker or the pattern more typical of the source event (a ball bouncing or a drumbeat). Under these conditions, there was evidence that both temporal and nontemporal cues were important in recognising theses stimuli. It is proposed that the interval between footsteps, which reflects a walker's cadence, is a cue for the recognition of the sounds of a human walking.

  18. Rapid detection of threshold VEPs.

    Science.gov (United States)

    Mackay, Alison M; Bradnam, Michael S; Hamilton, Ruth

    2003-06-01

    To determine whether a one-dimensional (1D) Laplacian analysis detects steady-state visual evoked potentials (ssVEPs) faster than the standard O(z)-F(z) montage and to establish the optimum position of Laplacian reference electrodes. Twenty-two normal adults were shown reversing checks ranging from 1.5' to 60'. Three electrode montages were investigated: O(z)-F(z), LO-F(z) and a 1D Laplacian analysis of 3 occipital electrodes (2O(z)-(RO+LO)). RO and LO were placed symmetrically and horizontally about O(z). Five different locations for RO and LO were investigated. Recordings were analysed in the frequency domain and the presence (and detection time, DT) or absence of a ssVEP defined statistically. Effects of individual, reference electrode site and check size on DT and phase differences between recording montages were investigated. Laplacian analysis detected ssVEPs to small (3') checks faster than O(z)-F(z), by 12.3 and 4.1s on average with Laplacian reference electrodes at 15 and 20% of half-head circumference, respectively. The optimum position of reference electrodes was governed by the instantaneous spatial spread of the response and the noise coherence between midline and lateral electrodes. A 1D Laplacian analysis can reduce the time to statistical detection of ssVEPs compared to the traditional O(z)-F(z) recording for stimuli near the normal acuity threshold of adults. This in turn could be used to minimise the length of a VEP acuity assessment.

  19. Auditory processing deficits are sometimes necessary and sometimes sufficient for language