A review of the progress and pitfalls of FDA policy process: Planning a pathway for pharmaceutical interventions for hearing loss development.
Abstract The Federal Food and Drug Administration, or FDA is generally considered a powerful gatekeeper, able to deliver or withhold life-saving cures and create or destroy economic windfalls. As the decades go by, and technologies, diseases, public health demands, and politics evolve, we can identify patterns of change, action and inter-action among some of these traditional stakeholders in the FDA's policy sphere. A careful examination of this agency's colorful history can shed light on central features of the agency's policy process, which has been quite receptive to its stakeholders and adaptive to change over...
Source: Hearing Research - November 11, 2016 Category: Audiology Authors: Hammill T Tags: Hear Res Source Type: research

An integrated model of pitch perception incorporating place and temporal pitch codes with application to cochlear implant research.
Abstract Although the neural mechanisms underlying pitch perception are not yet fully understood, there is general agreement that place and temporal representations of pitch are both used by the auditory system. This paper describes a neural network model of pitch perception that integrates both codes of pitch and explores the contributions of, and the interactions between, the two representations in simulated pitch ranking trials in normal and cochlear implant hearing. The model can replicate various psychophysical observations including the perception of the missing fundamental pitch and sensitivity to pitch int...
Source: Hearing Research - November 11, 2016 Category: Audiology Authors: Saeedi NE, Blamey PJ, Burkitt AN, Grayden DB Tags: Hear Res Source Type: research

Reply to: Psychometric properties of the Tinnitus Functional Index (TFI): Assessment in a UK research volunteer population.
PMID: 27842215 [PubMed - as supplied by publisher] (Source: Hearing Research)
Source: Hearing Research - November 10, 2016 Category: Audiology Authors: Henry JA, Thielman E, Zaugg T Tags: Hear Res Source Type: research

Masked speech perception across the adult lifespan: Impact of age and hearing impairment.
This study may contribute to the improvement of auditory rehabilitation programs aiming to prevent aging persons from missing out on conversations, which, in turn, will improve their quality of life. PMID: 27845259 [PubMed - as supplied by publisher] (Source: Hearing Research)
Source: Hearing Research - November 10, 2016 Category: Audiology Authors: Goossens T, Vercammen C, Wouters J, van Wieringen A Tags: Hear Res Source Type: research

A physiologically-inspired model reproducing the speech intelligibility benefit in cochlear implant listeners with residual acoustic hearing.
This study introduces a speech intelligibility model for cochlear implant users with ipsilateral preserved acoustic hearing that aims at simulating the observed speech-in-noise intelligibility benefit when receiving simultaneous electric and acoustic stimulation (EA-benefit). The model simulates the auditory nerve spiking in response to electric and/or acoustic stimulation. The temporally and spatially integrated spiking patterns were used as the final internal representation of noisy speech. Speech reception thresholds (SRTs) in stationary noise were predicted for a sentence test using an automatic speech recognition fram...
Source: Hearing Research - November 8, 2016 Category: Audiology Authors: Zamaninezhad L, Hohmann V, Büchner A, Schädler MR, Jürgens T Tags: Hear Res Source Type: research

Serotonin modulates response properties of neurons in the dorsal cochlear nucleus of the mouse.
In this study, we examined spiking activity of neurons in the dorsal cochlear nucleus (DCN) following iontophoretic application of 5-HT. The DCN is an early site in the auditory pathway that receives dense 5-HT fiber input from the raphe nuclei and has been implicated in the generation of auditory disorders marked by neuronal hyperexcitability. Recordings from the DCN in awake mice demonstrated that iontophoretic application of 5-HT had heterogeneous effects on spiking rate, spike timing, and evoked spiking threshold. We found that 56% of neurons exhibited increases in spiking rate during 5-HT delivery, while 22% had decre...
Source: Hearing Research - November 8, 2016 Category: Audiology Authors: Felix RA, Elde CJ, Nevue AA, Portfors CV Tags: Hear Res Source Type: research

Dynamic activation of basilar membrane macrophages in response to chronic sensory cell degeneration in aging mouse cochleae.
This study reveals that mature, fully differentiated tissue macrophages, not recently infiltrated monocytes, are the major macrophage population for immune responses to chronic sensory cell death. These macrophages display dynamic changes in their numbers and morphologies as age increases, and the changes are related to the phases of sensory cell degeneration. Notably, macrophage activation precedes sensory cell pathogenesis, and strong macrophage activity is maintained until sensory cell degradation is complete. Collectively, these findings suggest that mature tissue macrophages on the basilar membrane are a dynamic group...
Source: Hearing Research - November 8, 2016 Category: Audiology Authors: Frye MD, Yang W, Zhang C, Xiong B, Hu BH Tags: Hear Res Source Type: research

Abnormal auditory synchronization in stuttering: A magnetoencephalographic study.
Abstract In a previous magnetoencephalographic study, we showed both functional and structural reorganization of the right auditory cortex and impaired left auditory cortex function in people who stutter (PWS). In the present work, we reevaluated the same dataset to further investigate how the right and left auditory cortices interact to compensate for stuttering. We evaluated bilateral N100m latencies as well as indices of local and inter-hemispheric phase synchronization of the auditory cortices. The left N100m latency was significantly prolonged relative to the right N100m latency in PWS, while healthy control ...
Source: Hearing Research - November 4, 2016 Category: Audiology Authors: Kikuchi Y, Okamoto T, Ogata K, Hagiwara K, Umezaki T, Kenjo M, Nakagawa T, Tobimatsu S Tags: Hear Res Source Type: research

Visually guided auditory attention in a dynamic "cocktail-party" speech perception task: ERP evidence for age-related differences.
Visually guided auditory attention in a dynamic "cocktail-party" speech perception task: ERP evidence for age-related differences. Hear Res. 2016 Nov 4;: Authors: Getzmann DS, Wascher E Abstract Speech understanding in the presence of concurring sound is a major challenge especially for older persons. In particular, conversational turn-takings usually result in switch costs, as indicated by declined speech perception after changes in the relevant target talker. Here, we investigated whether visual cues indicating the future position of a target talker may reduce the costs of switching in you...
Source: Hearing Research - November 3, 2016 Category: Audiology Authors: Getzmann DS, Wascher E Tags: Hear Res Source Type: research

Lifetime leisure music exposure associated with increased frequency of tinnitus.
The objective measure of speech reception threshold had only a minimal relationship with tinnitus. Self-reported hearing difficulty was more strongly associated with tinnitus, but 76% of people reporting usual or constant tinnitus also reported little or no hearing difficulty. Overall, around 40% of participants of all ages reported never experiencing tinnitus, while 29% reported sometimes, usually or constantly experiencing tinnitus that lasted more than 5 minutes. Together, the results suggest that tinnitus is much more common than hearing loss, but that there is little association between the two, especially among the y...
Source: Hearing Research - November 3, 2016 Category: Audiology Authors: Moore DR, Zobay O, Mackinnon RC, Whitmer WM, Akeroyd MA Tags: Hear Res Source Type: research

Damage to inner ear structure during cochlear implantation: Correlation between insertion force and radio-histological findings in temporal bone specimens.
Abstract Cochlear implant insertion should be as least traumatic as possible in order to reduce trauma to the cochlear sensory structures. The force applied to the cochlea during array insertion should be controlled to limit insertion-related damage. The relationship between insertion force and histological traumatism remains to be demonstrated. Twelve freshly frozen cadaveric temporal bones were implanted with a long straight electrodes array through an anterior extended round window insertion using a motorized insertion tool with real-time measurement of the insertion force. Anatomical parameters, measured on a ...
Source: Hearing Research - November 3, 2016 Category: Audiology Authors: De Seta D, Torres R, Russo FY, Ferrary E, Kazmitcheff G, Heymann D, Amiaud J, Sterkers O, Bernardeschi D, Nguyen Y Tags: Hear Res Source Type: research

Maturation of middle ear transmission in children.
Abstract The goal of the current study was to characterize the normative features of wideband acoustic immittance in children for describing the functional maturation of the middle ear in 5 to 12-year-old children. Absorbance and group delay were measured in adults and three groups of children, 5-6, 7-9 and 10-12-year-olds, in a cross-sectional design. Absorbance showed significant effects of the age group in four out of ten center frequencies of one-half-octave bins from 211 to 6000 Hz, while there was no significant effect for group delay at any frequency. Older children (10-12 years) showed absorbance simi...
Source: Hearing Research - November 2, 2016 Category: Audiology Authors: Mishra SK, Dinger Z, Renken L Tags: Hear Res Source Type: research

Sensory coding and cognitive processing of sound in Veterans with blast exposure.
Abstract Recent anecdotal reports from VA audiology clinics as well as a few published studies have identified a sub-population of Service Members seeking treatment for problems communicating in everyday, noisy listening environments despite having normal to near-normal hearing thresholds. Because of their increased risk of exposure to dangerous levels of prolonged noise and transient explosive blast events, communication problems in these soldiers could be due to either hearing loss (traditional or "hidden") in the auditory sensory periphery or from blast-induced injury to cortical networks associated w...
Source: Hearing Research - November 1, 2016 Category: Audiology Authors: Bressler S, Goldberg H, Shinn-Cunningham B Tags: Hear Res Source Type: research

Effects of noise exposure on young adults with normal audiograms I: Electrophysiology.
ck CJ Abstract Noise-induced cochlear synaptopathy has been demonstrated in numerous rodent studies. In these animal models, the disorder is characterized by a reduction in amplitude of wave I of the auditory brainstem response (ABR) to high-level stimuli, whereas the response at threshold is unaffected. The aim of the present study was to determine if this disorder is prevalent in young adult humans with normal audiometric hearing. One hundred and twenty six participants (75 females) aged 18-36 were tested. Participants had a wide range of lifetime noise exposures as estimated by a structured interview. Audiometr...
Source: Hearing Research - November 1, 2016 Category: Audiology Authors: Prendergast G, Guest H, Munro KJ, Kluk K, Léger A, Hall DA, Heinz MG, Plack CJ Tags: Hear Res Source Type: research

Informational masking and the effects of differences in fundamental frequency and fundamental-frequency contour on phonetic integration in a formant ensemble.
This study explored the effects on speech intelligibility of across-formant differences in fundamental frequency (ΔF0) and F0 contour. Sentence-length speech analogues were presented dichotically (left=F1+F3; right=F2), either alone or-because competition usually reveals grouping cues most clearly-accompanied in the left ear by a competitor for F2 (F2C) that listeners must reject to optimize recognition. F2C was created by inverting the F2 frequency contour. In experiment 1, all left-ear formants shared the same constant F0 and ΔF0F2 was 0 or ±4 semitones. In experiment 2, all left-ear formants shared th...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Summers RJ, Bailey PJ, Roberts B Tags: Hear Res Source Type: research

Using individual differences to assess modulation-processing mechanisms and age effects.
This study used a correlational approach to clarify the mechanisms involved in modulation coding. Amplitude-modulation (AM) and frequency-modulation (FM) detection thresholds (AMDTs and FMDTs, respectively) were assessed for 70 normal-hearing listeners. In order to increase between-listeners variability in peripheral coding, participants with a wide range of age (20-70 years) were included. AMDTs and FMDTs were measured at a 5-Hz rate, using a 500-Hz sinusoidal carrier. FMDTs were also measured in the presence of an interfering AM to discourage the use of temporal-envelope cues. The results showed that AMDTs were significa...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Paraouty N, Lorenzi C Tags: Hear Res Source Type: research

Seasonal variations in auditory processing in the inferior colliculus of Eptesicus fuscus.
Abstract Eptesicus fuscus is typical of temperate zone bats in that both sexes undergo marked seasonal changes in behavior, endocrine status, and reproductive status. Acoustic communication plays a key role in many seasonal behaviors. For example, males emit specialized vocalizations during mating in the fall, and females use different specialized vocalizations to communicate with infants in late spring. Bats of both sexes use echolocation for foraging during times of activity, but engage in little sound-directed behavior during torpor and hibernation in winter. Auditory processing might be expected to reflect the...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Miller KE, Barr K, Krawczyk M, Covey E Tags: Hear Res Source Type: research

Evidence of activity-dependent plasticity in the dorsal cochlear nucleus, in  vivo, induced by brief sound exposure.
We examined the levels of multi- and single-unit spontaneous activity before and immediately following brief exposure (2 min) to tones at levels of either 109 or 85 dB SPL. Exposure frequency was selected to either correspond to the units' best frequency (BF) or fall within the borders of its inhibitory side band. The results demonstrate that these exposure conditions caused significant alterations in spontaneous activity and responses to BF tones. The induced changes have a fast onset (minutes) and are persistent for durations of at least 20 min. The directions of the change were found to depend on the freq...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Gao Y, Manzoor N, Kaltenbach JA Tags: Hear Res Source Type: research

Controlled exploration of the effects of conductive hearing loss on wideband acoustic immittance in human cadaveric preparations.
We report measurements before and after simulation of stapes fixation (n = 8), malleus fixation (n = 10), ossicular disarticulation (n = 10), and superior canal dehiscence (n = 8). Our results are consistent with the small set of previously published reflectance measurements made in temporal bones and patients. In this present study, these temporal bone experiments with different middle- and inner-ear pathologies were compared to the initial normal state by analyzing both WAI and ossicular motion, demonstrating that WAI can be a valuable tool in the diagnosis of conductive hearing lo...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Merchant GR, Merchant SN, Rosowski JJ, Nakajima HH Tags: Hear Res Source Type: research

Does the degree of linguistic experience (native versus nonnative) modulate the degree to which listeners can benefit from a delay between the onset of the maskers and the onset of the target speech?
Abstract Background noise has a greater adverse effect on word recognition when people are listening in their second language (L2) as opposed to their first language (L1). The present study investigates the extent to which linguistic experience affects the ability of L2 listeners to benefit from a delay between the onset of a masker and the onset of a word. In a previous study (Ben-David, Tse & Schneider, 2012), word recognition thresholds for young L1s were found to improve with the increase in the delay between the onset of a masker (either a stationary noise or a babble of voices) and the onset of a word. T...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Ben-David BM, Avivi-Reich M, Schneider BA Tags: Hear Res Source Type: research

Vestibular-dependent inter-stimulus interval effects on sound evoked potentials of central origin.
Abstract Todd et al. (2014ab) have recently demonstrated the presence of vestibular-dependent contributions to auditory evoked potentials (AEPs) when passing through the vestibular threshold as determined by vestibular evoked myogenic potentials (VEMPs), including a particular deflection labeled as an N42/P52 prior to the long-latency AEPs N1 and P2. In this paper we report the results of an experiment to determine the effect of inter-stimulus interval (ISI) and regularity on potentials recorded above and below VEMP threshold. Five healthy, right-handed subjects were recruited and evoked potentials were recor...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Todd NP, Govender S, Colebatch JG Tags: Hear Res Source Type: research

Frequency discrimination in the common marmoset (Callithrix jacchus).
Abstract The common marmoset (Callithrix jacchus) is a highly vocal New World primate species that has emerged in recent years as a promising model system for studies of auditory and vocal processing. Our recent studies have examined perceptual mechanisms related to the pitch of harmonic complex tones in this species. However, no previous psychoacoustic work has measured marmosets' frequency discrimination abilities for pure tones across a broad frequency range. Here we systematically examined frequency difference limens (FDLs), which measure the minimum discriminable frequency difference between two pure tones, i...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Osmanski MS, Song X, Guo Y, Wang X Tags: Hear Res Source Type: research

Effects of sustained release dexamethasone hydrogels in hearing preservation cochlear implantation.
r C Abstract It has been shown that glucocorticoids reduce the hearing threshold shifts associated with cochlear implantation. Previous studies evaluated the administration of glucocorticoids immediately before surgery or the repeated pre- or perioperative systemic application of glucocorticoids. The aim of this study was to evaluate the effects of a sustained release dexamethasone hydrogel in hearing preservation cochlear implantation. To address this issue, a guinea pig model of cochlear implantation was used. 30 normal hearing pigmented guinea pigs were randomized into a group receiving a single dose of a dexam...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Honeder C, Zhu C, Schöpper H, Gausterer JC, Walter M, Landegger LD, Saidov N, Riss D, Plasenzotti R, Gabor F, Arnoldner C Tags: Hear Res Source Type: research

Across-site patterns of electrically evoked compound action potential amplitude-growth functions in multichannel cochlear implant recipients and the effects of the interphase gap.
Abstract Electrically evoked compound action potential (ECAP) measures of peak amplitude, and amplitude-growth function (AGF) slope have been shown to reflect characteristics of cochlear health (primarily spiral ganglion density) in anesthetized cochlear-implanted guinea pigs. Likewise, the effect of increasing the interphase gap (IPG) in each of these measures also reflects SGN density in the implanted guinea pig. Based on these findings, we hypothesize that suprathreshold ECAP measures, and also how they change as the IPG is increased, have the potential to be clinically applicable in human subjects. However, fu...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Schvartz-Leyzac KC, Pfingst BE Tags: Hear Res Source Type: research

Differences in synaptic and intrinsic properties result in topographic heterogeneity of temporal processing of neurons within the inferior colliculus.
Abstract The identification and characterization of organization principals is essential for the understanding of neural function of brain areas. The inferior colliculus (IC) represents a midbrain nexus involved in numerous aspects of auditory processing. Likewise, neurons throughout the IC are tuned to a diverse range of specific stimulus features. Yet beyond a topographic arrangement of the cochlea-inherited frequency tuning, the functional organization of the IC is not well understood. Particularly, a common principle that links the diverse tuning characteristics is unknown. Here we used in vitro patch cla...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Yassin L, Pecka M, Kajopoulos J, Gleiss H, Li L, Leibold C, Felmy F Tags: Hear Res Source Type: research

Low-frequency bias tone suppression of auditory-nerve responses to low-level clicks and tones.
Abstract We used low-frequency "bias" tones (BT's) to explore whether click and tone responses are affected in the same way by cochlear active processes. In nonlinear systems the responses to clicks are not always simply related to the responses to tones. Cochlear amplifier gain depends on the incremental slope of the outer-hair-cell (OHC) stereocilia mechano-electric transduction (MET) function. BTs transiently change the operating-point of OHC MET channels and can suppress cochlear-amplifier gain by pushing OHC METs into low-slope saturation regions. BT effects on single auditory-nerve (AN) fibers have...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Nam H, Guinan JJ Tags: Hear Res Source Type: research

Endothelin-1 mediated induction of extracellular matrix genes in strial marginal cells underlies strial pathology in Alport mice.
Abstract Alport syndrome, a type IV collagen disorder, manifests as glomerular disease associated with hearing loss with thickening of the glomerular and strial capillary basement membranes (SCBMs). We have identified a role for endothelin-1 (ET-1) activation of endothelin A receptors (ETARs) in glomerular pathogenesis. Here we explore whether ET-1 plays a role in strial pathology. Wild type (WT) and Alport mice were treated with the ETAR antagonist, sitaxentan. The stria vascularis was analyzed for SCBM thickness and for extracellular matrix (ECM) proteins. Additional WT and Alport mice were exposed to noise or h...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Meehan DT, Delimont D, Dufek B, Zallocchi M, Phillips G, Gratton MA, Cosgrove D Tags: Hear Res Source Type: research

The contribution of inferior colliculus activity to the auditory brainstem response (ABR) in mice.
In conclusion, the slow ABR wave P0 in the scalp ABR may represent a complementary non-invasive marker for IC activity in the mouse. Further, the latency of synchronized click-evoked activity in the IC supports the view that IC contributes to ABR wave V, and possibly also to ABR wave IV. PMID: 27562195 [PubMed - in process] (Source: Hearing Research)
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Land R, Burghard A, Kral A Tags: Hear Res Source Type: research

The effects of aging and sex on detection of ultrasonic vocalizations by adult CBA/CaJ mice (Mus musculus).
In conclusion, the results highlight the importance of studying complex signals across the lifespan. PMID: 27579993 [PubMed - in process] (Source: Hearing Research)
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Kobrina A, Dent ML Tags: Hear Res Source Type: research

Modelling the effect of round window stiffness on residual hearing after cochlear implantation.
Abstract Preservation of residual hearing after cochlear implantation is now considered an important goal of surgery. However, studies indicate an average post-operative hearing loss of around 20 dB at low frequencies. One factor which may contribute to post-operative hearing loss, but which has received little attention in the literature to date, is the increased stiffness of the round window, due to the physical presence of the cochlear implant, and to its subsequent thickening or to bone growth around it. A finite element model was used to estimate that there is approximately a 100-fold increase in th...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Elliott SJ, Ni G, Verschuur CA Tags: Hear Res Source Type: research

A tri-coil bellows-type round window transducer with improved frequency characteristics for middle-ear implants.
In this study, a new tri-coil bellows-type transducer (TCBT), which has excellent low frequency output and is easy to implant, is proposed. To design the frequency characteristics of the TCBT, mechanical and electrical simulations were performed, and then a comparative analysis was conducted between a floating mass type transducer (like the FMT) and a fixed type transducer (like the TCBT). The features of the proposed TCBT are as follows. First, the TCBT's housing is fixed to the RW niche so that it does not vibrate. Second, the internal end of a tiny bellows is connected to a vibrating three-pole permanent magnet located ...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Shin DH, Seong KW, Puria S, Lee KY, Cho JH Tags: Hear Res Source Type: research

A fast, stochastic, and adaptive model of auditory nerve responses to cochlear implant stimulation.
In this study, a computationally efficient model that accurately predicts auditory nerve responses to CI pulse train input was developed. A three-dimensional volume conduction and active nerve model developed at Leiden University Medical Center was extended with stochasticity, adaptation, and accommodation. This complete model includes spatial and temporal characteristics of both the cochlea and the auditory nerve. The model was validated by comparison with experimentally measured single fiber action potential responses to pulse trains published in the literature. The effects of pulse rate and pulse amplitude on spiking pa...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: van Gendt MJ, Briaire JJ, Kalkman RK, Frijns JH Tags: Hear Res Source Type: research

Speech perception adjusts to stable spectrotemporal properties of the  listening environment.
Speech perception adjusts to stable spectrotemporal properties of the listening environment. Hear Res. 2016 Nov;341:168-178 Authors: Stilp CE, Anderson PW, Assgari AA, Ellis GM, Zahorik P Abstract When perceiving speech, listeners compensate for reverberation and stable spectral peaks in the speech signal. Despite natural listening conditions usually adding both reverberation and spectral coloration, these processes have only been studied separately. Reverberation smears spectral peaks across time, which is predicted to increase listeners' compensation for these peaks. This prediction was tested ...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Stilp CE, Anderson PW, Assgari AA, Ellis GM, Zahorik P Tags: Hear Res Source Type: research

The effect of distraction on change detection in crowded acoustic scenes.
Abstract In this series of behavioural experiments we investigated the effect of distraction on the maintenance of acoustic scene information in short-term memory. Stimuli are artificial acoustic 'scenes' composed of several (up to twelve) concurrent tone-pip streams ('sources'). A gap (1000 ms) is inserted partway through the 'scene'; Changes in the form of an appearance of a new source or disappearance of an existing source, occur after the gap in 50% of the trials. Listeners were instructed to monitor the unfolding 'soundscapes' for these events. Distraction was measured by presenting distractor stimuli du...
Source: Hearing Research - October 31, 2016 Category: Audiology Authors: Petsas T, Harrison J, Kashino M, Furukawa S, Chait M Tags: Hear Res Source Type: research

Effects of long-term non-traumatic noise exposure on the adult central auditory system. Hearing problems without hearing loss.
Abstract It is known that hearing loss induces plastic changes in the brain, causing loudness recruitment and hyperacusis, increased spontaneous firing rates and neural synchrony, reorganizations of the cortical tonotopic maps, and tinnitus. Much less in known about the central effects of exposure to sounds that cause a temporary hearing loss, affect the ribbon synapses in the inner hair cells, and cause a loss of high-threshold auditory nerve fibers. In contrast there is a wealth of information about central effects of long-duration sound exposures at levels ≤ 80 dB SPL that do not even cause a temporary heari...
Source: Hearing Research - October 24, 2016 Category: Audiology Authors: Eggermont JJ Tags: Hear Res Source Type: research

Electro-acoustic pitch matching experiments in patients with single-sided deafness and a cochlear implant: Is there a need for adjustment of the default frequency allocation tables?
Abstract Patients with single-sided deafness (SSD) and a cochlear implant (CI) can compare the pitch of stimulated electrodes and acoustic tones. A pitch mismatch may negatively bear on the fusion of the signals from the two ears, which may limit auditory performance. We aimed to explore this mismatch, correlate it to performance, and finally to discuss its possible clinical consequences. Ten patients with SSD and a CI (Cochlear Ltd.) compared the pitch of electrical and acoustic stimuli. Patients had to choose one of two acoustic stimuli, with the pitch closest to the pitch of the electrical stimulus at electrode...
Source: Hearing Research - October 23, 2016 Category: Audiology Authors: Peters JP, Bennink E, Grolman W, van Zanten GA Tags: Hear Res Source Type: research

Long-term noise exposures: A brief review.
PMID: 27780746 [PubMed - as supplied by publisher] (Source: Hearing Research)
Source: Hearing Research - October 21, 2016 Category: Audiology Authors: Davis R Tags: Hear Res Source Type: research

Effects of brain-derived neurotrophic factor (BDNF) on the cochlear nucleus in cats deafened as neonates.
PMID: 27773647 [PubMed - as supplied by publisher] (Source: Hearing Research)
Source: Hearing Research - October 19, 2016 Category: Audiology Authors: Kandathil CK, Stakhovskaya O, Leake PA Tags: Hear Res Source Type: research

Editorial introduction: Special issue on plasticity following hearing loss and deafness.
PMID: 27771426 [PubMed - as supplied by publisher] (Source: Hearing Research)
Source: Hearing Research - October 18, 2016 Category: Audiology Authors: Butler BE, Meredith MA, Lomber SG Tags: Hear Res Source Type: research

Performance in noise: Impact of reduced speech intelligibility on Sailor performance in a Navy command and control environment.
Abstract Noise, hearing loss, and electronic signal distortion, which are common problems in military environments, can impair speech intelligibility and thereby jeopardize mission success. The current study investigated the impact that impaired communication has on operational performance in a command and control environment by parametrically degrading speech intelligibility in a simulated shipborne Combat Information Center. Experienced U.S. Navy personnel served as the study participants and were required to monitor information from multiple sources and respond appropriately to communications initiated by inves...
Source: Hearing Research - October 18, 2016 Category: Audiology Authors: Keller MD, Ziriax JM, Barns W, Sheffield B, Brungart D, Thomas T, Jaeger B, Yankaskas K Tags: Hear Res Source Type: research

The influence of memory and attention on the ear advantage in dichotic listening.
Abstract The role of memory retention and attentional control on hemispheric asymmetry was investigated using a verbal dichotic listening paradigm, with the consonant-vowel syllables (/ba/,/da/,/ga/,/ka/,/pa/and/ta/), while manipulating the focus of attention and the time interval between stimulus and response. Attention was manipulated using three conditions: non-forced (NF), forced left (FL) and forced right (FR) attention. Memory involvement was varied using four delays (0, 1, 3 and 4 s) between stimulus presentation and response. Results showed a significant right ear advantage (REA) in the NF condition a...
Source: Hearing Research - October 18, 2016 Category: Audiology Authors: D'Anselmo A, Marzoli D, Brancucci A Tags: Hear Res Source Type: research

Category selectivity of the N170 and the role of expertise in deaf signers.
This study was designed to characterize the effects of early deafness and lifelong sign language use on visual category sensitivity of the N170 event-related potential. Images from nine categories of visual forms including upright faces, inverted faces, and hands were presented to twelve typically hearing adults and twelve adult congenitally deaf signers. Classic N170 category sensitivity was observed in both participant groups, whereby faces elicited larger amplitudes than all other visual categories, and inverted faces elicited larger amplitudes and slower latencies than upright faces. In hearing adults, hands elicited a...
Source: Hearing Research - October 18, 2016 Category: Audiology Authors: Mitchell TV Tags: Hear Res Source Type: research

Musicians' edge: A comparison of auditory processing, cognitive abilities and statistical learning.
Abstract It has been hypothesized that musical expertise is associated with enhanced auditory processing and cognitive abilities. Recent research has examined the relationship between musicians' advantage and implicit statistical learning skills. In the present study, we assessed a variety of auditory processing skills, cognitive processing skills, and statistical learning (auditory and visual forms) in age-matched musicians (N = 17) and non-musicians (N = 18). Musicians had significantly better performance than non-musicians on frequency discrimination, and backward digit span. A key finding w...
Source: Hearing Research - October 18, 2016 Category: Audiology Authors: Mandikal Vasuki PR, Sharma M, Demuth K, Arciuli J Tags: Hear Res Source Type: research

Spatial and temporal disparity in signals and maskers affects signal detection in non-human primates.
Abstract Detection thresholds for auditory stimuli (signals) increase in the presence of maskers. Natural environments contain maskers/distractors that can have a wide range of spatiotemporal properties relative to the signal. While these parameters have been well explored psychophysically in humans, they have not been well explored in animal models, and their neuronal underpinnings are not well understood. As a precursor to the neuronal measurements, we report the effects of systematically varying the spatial and temporal relationship between signals and noise in macaque monkeys (Macaca mulatta and Macaca radiata...
Source: Hearing Research - October 18, 2016 Category: Audiology Authors: Rocchi F, Dylla ME, Bohlen PA, Ramachandran R Tags: Hear Res Source Type: research

Hearing testing in the U.S. Department of Defense: Potential impact on Veterans Affairs hearing loss disability awards.
Abstract Hearing loss is the second most common disability awarded by the U.S. Department of Veterans Affairs (VA) to former members of the U.S. uniformed services. Hearing readiness and conservation practices differ among the four largest uniformed military services (Air Force, Army, Marine Corps, and Navy). Utilizing a data set consisting of all hearing loss claims submitted to the VA from fiscal years 2003-2013, we examined characteristics of veterans submitting claims within one year of separation from military service. Our results indicate that having a hearing loss disability claim granted was significantly ...
Source: Hearing Research - October 17, 2016 Category: Audiology Authors: Nelson JT, Swan AA, Swiger B, Packer M, Pugh MJ Tags: Hear Res Source Type: research

Developmental hearing loss impedes auditory task learning and performance in gerbils.
Abstract The consequences of developmental hearing loss have been reported to include both sensory and cognitive deficits. To investigate these issues in a non-human model, auditory learning and asymptotic psychometric performance were compared between normal hearing (NH) adult gerbils and those reared with conductive hearing loss (CHL). At postnatal day 10, before ear canal opening, gerbil pups underwent bilateral malleus removal to induce a permanent CHL. Both CHL and control animals were trained to approach a water spout upon presentation of a target (Go stimuli), and withhold for foils (Nogo stimuli). To asses...
Source: Hearing Research - October 12, 2016 Category: Audiology Authors: von Trapp G, Aloni I, Young S, Semple MN, Sanes DH Tags: Hear Res Source Type: research

Early age noise exposure increases loudness perception - A novel animal model of hyperacusis.
Abstract The neural mechanisms that give rise to hyperacusis, a reduction in loudness tolerance, are largely unknown. Some reports suggest that hyperacusis is linked to childhood hearing loss. However, the evidence for this is largely circumstantial. In order to rigorously test this hypothesis, we studied loudness changes in rats caused by intense noise exposure (12 kHz narrow band noise, 115 dB SPL, 4 h) at postnatal 16 days. Rats without noise exposure were used as controls. The exposed noise group (n = 7) showed a mean 40-50 dB hearing loss compared to the control group (n =&n...
Source: Hearing Research - October 12, 2016 Category: Audiology Authors: Alkharabsheh A, Xiong F, Manohar S, Chen G, Salvi R, Sun W Tags: Hear Res Source Type: research

Effects of noise on speech recognition: Challenges for communication by service members.
This article provides readers with an overview of the challenges associated with speech communication in noisy backgrounds, as well as its assessment and potential impact on functional performance, and provides guidance for important new research directions relevant not only to military personnel, but also to employees who work in high noise environments. PMID: 27743882 [PubMed - as supplied by publisher] (Source: Hearing Research)
Source: Hearing Research - October 11, 2016 Category: Audiology Authors: Le Prell CG, Clavier O Tags: Hear Res Source Type: research

Perilymph pharmacokinetics of locally-applied gentamicin in the guinea pig.
In this study, gentamicin was applied to the round window niche as a 20 μL bolus of 40 mg/ml solution. Ten 2 μL samples of perilymph were collected sequentially from the lateral semi-circular canal (LSCC) at times from 1 to 4 h after application. Gentamicin concentration was typically highest in samples originating from the vestibule and was lower in samples originating from scala tympani. To interpret these results, perilymph elimination kinetics for gentamicin was quantified by loading the entire perilymph space by injection at the LSCC with a 500 μg/ml gentamicin solution followed by se...
Source: Hearing Research - October 7, 2016 Category: Audiology Authors: Salt AN, Hartsock JJ, Gill RM, King E, Kraus FB, Plontke SK Tags: Hear Res Source Type: research

Top-down and bottom-up neurodynamic evidence in patients with tinnitus.
Abstract Although a peripheral auditory (bottom-up) deficit is an essential prerequisite for the generation of tinnitus, central cognitive (top-down) impairment has also been shown to be an inherent neuropathological mechanism. Using an auditory oddball paradigm (for top-down analyses) and a passive listening paradigm (for bottom-up analyses) while recording electroencephalograms (EEGs), we investigated whether top-down or bottom-up components were more critical in the neuropathology of tinnitus, independent of peripheral hearing loss. We observed significantly reduced P300 amplitudes (reflecting fundamental cogni...
Source: Hearing Research - October 7, 2016 Category: Audiology Authors: Hong SK, Park S, Ahn MH, Min BK Tags: Hear Res Source Type: research