OtoRhinoLaryngology by Sfakianakis G.Alexandros Sfakianakis G.Alexandros,Anapafseos 5 Agios Nikolaos 72100 Crete Greece,tel : 00302841026182,00306932607174
Δευτέρα 31 Οκτωβρίου 2016
Sound perception and the importance of context
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Sound perception and the importance of context
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Sound perception and the importance of context
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How to Overcome the Struggles of Pediatric Hearing Loss
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How to Overcome the Struggles of Pediatric Hearing Loss
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How to Overcome the Struggles of Pediatric Hearing Loss
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Κυριακή 30 Οκτωβρίου 2016
Distinct capacity for differentiation to inner ear cell types by progenitor cells of the cochlea and vestibular organs.
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Distinct capacity for differentiation to inner ear cell types by progenitor cells of the cochlea and vestibular organs.
Development. 2016 Oct 27;:
Authors: McLean WJ, McLean DT, Eatock RA, Edge AS
Abstract
Disorders of hearing and balance are most commonly associated with damage to cochlear and vestibular hair cells or neurons. Although these cells are not capable of spontaneous regeneration, progenitor cells in the hearing and balance organs of the neonatal mammalian inner ear have the capacity to generate new hair cells after damage. To investigate whether these cells were restricted in their differentiation capacity, we assessed the phenotypes of differentiated progenitor cells isolated from three compartments of the inner ear - the vestibular and cochlear sensory epithelia and the spiral ganglion - by measuring electrophysiological properties and gene expression. Lgr5+ progenitor cells from the sensory epithelia gave rise to hair cell-like cells, but not neurons or glial cells. Newly created hair cell-like cells had hair bundle proteins, synaptic proteins, and membrane proteins characteristic of the compartment of origin. PLP+ glial cells from the spiral ganglion were identified as neural progenitors, which gave rise to neurons, astrocytes, and oligodendrocytes, but not hair cells. Thus, distinct progenitor populations from the neonatal inner ear differentiate to cell types associated with their organ of origin.
PMID: 27789624 [PubMed - as supplied by publisher]
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Distinct capacity for differentiation to inner ear cell types by progenitor cells of the cochlea and vestibular organs.
Related Articles |
Distinct capacity for differentiation to inner ear cell types by progenitor cells of the cochlea and vestibular organs.
Development. 2016 Oct 27;:
Authors: McLean WJ, McLean DT, Eatock RA, Edge AS
Abstract
Disorders of hearing and balance are most commonly associated with damage to cochlear and vestibular hair cells or neurons. Although these cells are not capable of spontaneous regeneration, progenitor cells in the hearing and balance organs of the neonatal mammalian inner ear have the capacity to generate new hair cells after damage. To investigate whether these cells were restricted in their differentiation capacity, we assessed the phenotypes of differentiated progenitor cells isolated from three compartments of the inner ear - the vestibular and cochlear sensory epithelia and the spiral ganglion - by measuring electrophysiological properties and gene expression. Lgr5+ progenitor cells from the sensory epithelia gave rise to hair cell-like cells, but not neurons or glial cells. Newly created hair cell-like cells had hair bundle proteins, synaptic proteins, and membrane proteins characteristic of the compartment of origin. PLP+ glial cells from the spiral ganglion were identified as neural progenitors, which gave rise to neurons, astrocytes, and oligodendrocytes, but not hair cells. Thus, distinct progenitor populations from the neonatal inner ear differentiate to cell types associated with their organ of origin.
PMID: 27789624 [PubMed - as supplied by publisher]
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Σάββατο 29 Οκτωβρίου 2016
A Formant Range Profile for Singers
Source:Journal of Voice
Author(s): Ingo R. Titze, Lynn M. Maxfield, Megan C. Walker
Vowel selection is important in differentiating between singing styles. The timbre of the vocal instrument, which is related to its frequency spectrum, is governed by both the glottal sound source and the vowel choices made by singers. Consequently, the ability to modify the vowel space is a measure of how successfully a singer can maintain a desired timbre across a range of pitches. Formant range profiles were produced as a means of quantifying this ability. Seventy-seven subjects (including trained and untrained vocalists) participated, producing vowels with three intended mouth shapes: (1) neutral or speech-like, (2) megaphone-shaped (wide open mouth), and (3) inverted-megaphone-shaped (widened oropharynx with moderate mouth opening). The first and second formant frequencies (F1 and F2) were estimated with fry phonation for each shape and values were plotted in F1-F2 space. By taking four vowels of a quadrangle /i, æ, a, u/, the resulting area was quantified in kHz2 (kHz squared) as a measure of the subject's ability to modify their vocal tract for spectral differences.
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Period for Normalization of Voice Acoustic Parameters in Indian Pediatric Cochlear Implantees
Source:Journal of Voice
Author(s): Jeena V. Joy, Shweta Deshpande, Dr. Neelam Vaid
ObjectiveThe purpose of this study was to investigate the duration required by children with cochlear implants to approximate the norms of voice acoustic parameters.Study DesignThe study design is retrospective.MethodsThirty children with cochlear implants (chronological ages ranging between 4.1 and 6.7 years) were divided into three groups, based on the postimplantation duration. Ten normal-hearing children (chronological ages ranging between 4 and 7 years) were selected as the control group. All implanted children underwent an objective voice analysis using Dr. Speech software (Tiger DRS, Inc., Seattle, WA, USA) at 6 months and at 1 and 2 years of implant use. Voice analysis was done for the children in the control group and means were derived for all the parameters analyzed to obtain the normal values. Habitual fundamental frequency (HFF), jitter (frequency variation), and shimmer (amplitude variation) were the voice acoustic parameters analyzed for the vowels |a|, |i|, and |u|. The obtained values of these parameters were then compared with the norms.ResultsHFF for the children with implant use for 6 months and 1 year did significantly differ from the control group. However, there was no significant difference (P > 0.5) observed in the children with implant use for 2 years, thus matching the norms. Jitter and shimmer showed a significant difference (P < 0.5) even at 2 years of implant use when compared with the control group.ConclusionsThe findings of the study divulge that children with cochlear implants approximate age-matched normal-hearing kids with respect to the voice acoustic parameter of HFF by 2 years of implant use. However, jitter and shimmer were not found to stabilize for the duration studied.
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Speech Adjustments for Room Acoustics and Their Effects on Vocal Effort
Source:Journal of Voice
Author(s): Pasquale Bottalico
ObjectivesThe aims of the present study are (1) to analyze the effects of the acoustical environment and the voice style on time dose (Dt_p) and fundamental frequency (mean f0 and standard deviation std_f0) while taking into account the effect of short-term vocal fatigue and (2) to predict the self-reported vocal effort from the voice acoustical parameters.MethodsTen male and ten female subjects were recorded while reading a text in normal and loud styles, in three rooms—anechoic, semi-reverberant, and reverberant—with and without acrylic glass panels 0.5 m from the mouth, which increased external auditory feedback. Subjects quantified how much effort was required to speak in each condition on a visual analogue scale after each task.Results(Aim1) In the loud style, Dt_p, f0, and std_f0 increased. The Dt_p was higher in the reverberant room compared to the other two rooms. Both genders tended to increase f0 in less reverberant environments, whereas a more monotonous speech was produced in rooms with greater reverberation. All three voice parameters increased with short-term vocal fatigue. (Aim2) A model of the vocal effort to acoustic vocal parameters is proposed. The sound pressure level contributed to 66% of the variance explained by the model, followed by the f0 (30%) and the modulation in amplitude (4%).ConclusionsThe results provide insight into how voice acoustical parameters can predict vocal effort. In particular, it increased when SPL and f0 increased and when the amplitude voice modulation decreased.
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Joint Engagement and Early Language in Young Children With Fragile X Syndrome
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Epidemiology of Vocal Health in Young Adults Attending College in the United States
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Comprehension of Inferences in a Narrative in 3- to 6-Year-Old Children
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An Item Analysis of the French Version of the Test for Reception of Grammar Among Children and Adolescents With Down Syndrome or Intellectual Disability of Undifferentiated Etiology
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Towards a Theory of Learning for Naming Rehabilitation: Retrieval Practice and Spacing Effects
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Short-Term Memory Performance in 7- and 8-Year-Old Children: The Relationship Between Phonological and Pitch Processing
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Automated Proposition Density Analysis for Discourse in Aphasia
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Exploring the Clinical Utility of Relative Fundamental Frequency as an Objective Measure of Vocal Hyperfunction
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Objective Measure of Nasal Air Emission Using Nasal Accelerometry
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Dyslexia Limits the Ability to Categorize Talker Dialect
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Effects of Biofeedback on Control and Generalization of Nasalization in Typical Speakers
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Effects of Noise on Speech Recognition and Listening Effort in Children With Normal Hearing and Children With Mild Bilateral or Unilateral Hearing Loss
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Screening for Language Delay: Growth Trajectories of Language Ability in Low- and High-Performing Children
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The Palin Parent Rating Scales: Parents' Perspectives of Childhood Stuttering and Its Impact
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Examining the Language Phenotype in Children With Typical Development, Specific Language Impairment, and Fragile X Syndrome
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Glimpsing Speech in the Presence of Nonsimultaneous Amplitude Modulations From a Competing Talker: Effect of Modulation Rate, Age, and Hearing Loss
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Longitudinal Effects on Early Adolescent Language: A Twin Study
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Patient-Reported Measures of Hearing Loss and Tinnitus in Pediatric Cancer and Hematopoietic Stem Cell Transplantation: A Systematic Review
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Executive Functions in Children With Specific Language Impairment: A Meta-Analysis
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Lidcombe Program Webcam Treatment for Early Stuttering: A Randomized Controlled Trial
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Joint Engagement and Early Language in Young Children With Fragile X Syndrome
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Epidemiology of Vocal Health in Young Adults Attending College in the United States
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Comprehension of Inferences in a Narrative in 3- to 6-Year-Old Children
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An Item Analysis of the French Version of the Test for Reception of Grammar Among Children and Adolescents With Down Syndrome or Intellectual Disability of Undifferentiated Etiology
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Towards a Theory of Learning for Naming Rehabilitation: Retrieval Practice and Spacing Effects
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Short-Term Memory Performance in 7- and 8-Year-Old Children: The Relationship Between Phonological and Pitch Processing
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Automated Proposition Density Analysis for Discourse in Aphasia
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Exploring the Clinical Utility of Relative Fundamental Frequency as an Objective Measure of Vocal Hyperfunction
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Objective Measure of Nasal Air Emission Using Nasal Accelerometry
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Dyslexia Limits the Ability to Categorize Talker Dialect
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Effects of Biofeedback on Control and Generalization of Nasalization in Typical Speakers
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Effects of Noise on Speech Recognition and Listening Effort in Children With Normal Hearing and Children With Mild Bilateral or Unilateral Hearing Loss
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Screening for Language Delay: Growth Trajectories of Language Ability in Low- and High-Performing Children
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The Palin Parent Rating Scales: Parents' Perspectives of Childhood Stuttering and Its Impact
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Examining the Language Phenotype in Children With Typical Development, Specific Language Impairment, and Fragile X Syndrome
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Glimpsing Speech in the Presence of Nonsimultaneous Amplitude Modulations From a Competing Talker: Effect of Modulation Rate, Age, and Hearing Loss
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Longitudinal Effects on Early Adolescent Language: A Twin Study
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Patient-Reported Measures of Hearing Loss and Tinnitus in Pediatric Cancer and Hematopoietic Stem Cell Transplantation: A Systematic Review
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Executive Functions in Children With Specific Language Impairment: A Meta-Analysis
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Lidcombe Program Webcam Treatment for Early Stuttering: A Randomized Controlled Trial
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Joint Engagement and Early Language in Young Children With Fragile X Syndrome
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Epidemiology of Vocal Health in Young Adults Attending College in the United States
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Comprehension of Inferences in a Narrative in 3- to 6-Year-Old Children
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An Item Analysis of the French Version of the Test for Reception of Grammar Among Children and Adolescents With Down Syndrome or Intellectual Disability of Undifferentiated Etiology
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Towards a Theory of Learning for Naming Rehabilitation: Retrieval Practice and Spacing Effects
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Short-Term Memory Performance in 7- and 8-Year-Old Children: The Relationship Between Phonological and Pitch Processing
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Automated Proposition Density Analysis for Discourse in Aphasia
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Παρασκευή 28 Οκτωβρίου 2016
Estimation of Round-Trip Outer-Middle Ear Gain Using DPOAEs
Abstract
The reported research introduces a noninvasive approach to estimate round-trip outer-middle ear pressure gain using distortion product otoacoustic emissions (DPOAEs). Our ability to hear depends primarily on sound waves traveling through the outer and middle ear toward the inner ear. The role of the outer and middle ear in sound transmission is particularly important for otoacoustic emissions (OAEs), which are sound signals generated in a healthy cochlea and recorded by a sensitive microphone placed in the ear canal. OAEs are used to evaluate the health and function of the cochlea; however, they are also affected by outer and middle ear characteristics. To better assess cochlear health using OAEs, it is critical to quantify the effect of the outer and middle ear on sound transmission. DPOAEs were obtained in two conditions: (i) two-tone and (ii) three-tone. In the two-tone condition, DPOAEs were generated by presenting two primary tones in the ear canal. In the three-tone condition, DPOAEs at the same frequencies (as in the two-tone condition) were generated by the interaction of the lower frequency primary tone in the two-tone condition with a distortion product generated by the interaction of two other external tones. Considering how the primary tones and DPOAEs of the aforementioned conditions were affected by the forward and reverse outer-middle ear transmission, an estimate of the round-trip outer-middle ear pressure gain was obtained. The round-trip outer-middle ear gain estimates ranged from −39 to −17 dB between 1 and 3.3 kHz.
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Discovery of CDH23 as a Significant Contributor to Progressive Postlingual Sensorineural Hearing Loss in Koreans
by Bong Jik Kim, Ah Reum Kim, Chung Lee, So Young Kim, Nayoung K. D. Kim, Mun Young Chang, Jihye Rhee, Mi-Hyun Park, Soo Kyung Koo, Min Young Kim, Jin Hee Han, Seung-ha Oh, Woong-Yang Park, Byung Yoon Choi
CDH23 mutations have mostly been associated with prelingual severe-to-profound sensorineural hearing loss (SNHL) in either syndromic or nonsyndromic SNHL (DFNB12). Herein, we demonstrate the contribution of CDH23 mutations to postlingual nonsyndromic SNHL (NS-SNHL). We screened 32 Korean adult probands with postlingual NS-SNHL sporadically or in autosomal recessive fashion using targeted panel or whole exome sequencing. We identified four (12.5%, 4/32) potential postlingual DFNB12 families that segregated the recessive CDH23 variants, qualifying for our criteria along with rapidly progressive SNHL. Three of the four families carried one definite pathogenic CDH23 variant previously known as the prelingual DFNB12 variant in a trans configuration with rare CDH23 variants. To determine the contribution of rare CDH23 variants to the postlingual NS-SNHL, we checked the minor allele frequency (MAF) of CDH23 variants detected from our postlingual NS-SNHL cohort and prelingual NS-SNHL cohort, among the 2040 normal control chromosomes. The allele frequency of these CDH23 variants in our postlingual cohort was 12.5%, which was significantly higher than that of the 2040 control chromosomes (5.53%), confirming the contribution of these rare CDH23 variants to postlingual NS-SNHL. Furthermore, MAF of rare CDH23 variants from the postlingual NS-SNHL group was significantly higher than that from the prelingual NS-SNHL group. This study demonstrates an important contribution of CDH23 mutations to poslingual NS-SNHL and shows that the phenotypic spectrum of DFNB12 can be broadened even into the presbycusis, depending on the pathogenic potential of variants. We also propose that pathogenic potential of CDH23 variants and the clinical fate of DFNB12 may be predicted by MAF.from #Audiology via xlomafota13 on Inoreader http://ift.tt/2e58bJF
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Application of SNPscan in Genetic Screening for Common Hearing Loss Genes
by Zixuan Gao, Yu Lu, Jia Ke, Tao Li, Ping Hu, Yu Song, Chiyu Xu, Jie Wang, Jing Cheng, Lei Zhang, Hong Duan, Huijun Yuan, Furong Ma
The current study reports the successful application of a fast and efficient genetic screening system for common hearing loss (HL) genes based on SNPscan genotyping technology. Genetic analysis of 115 variants in common genes related to HL, GJB2, SLC26A4 and MT-RNR, was performed on 695 subjects with non-syndromic hearing loss (NSHL) from the Northern China. The results found that 38.7% (269/695) of cases carried bi-allelic pathogenic variants in GJB2 and SLC26A4 and 0.7% (5/695) of cases carried homoplasmic MT-RNR1 variants. The variant allele frequency of GJB2, SLC26A4 and MT-RNR1 was 19.8% (275/1390), 21.9% (304/1390), and 0.86% (6/695), respectively. This approach can explain ~40% of NSHL cases and thus is a useful tool for establishing primary molecular diagnosis of NSHL in clinical genetics.from #Audiology via xlomafota13 on Inoreader http://ift.tt/2eZSbGs
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Πέμπτη 27 Οκτωβρίου 2016
Otoacoustic Emission Estimates of Human Basilar Membrane Impulse Response Duration and Cochlear Filter Tuning
Source:Hearing Research
Author(s): Stefan Raufer, Sarah Verhulst
This study describes a method based on temporal suppression of click-evoked otoacoustic emissions (CEOAEs) to estimate the time course and duration of human basilar membrane impulse responses (BM IRs). This was achieved by tracing the suppression of dominant peaks in the CEOAE spectrum as a function of the temporal separation between two equal-level stimulus clicks. The relationship between the suppression pattern and underlying BM IR duration near the generation site of the CEOAE frequency was established using model simulations. To relate BM IR duration estimates to cochlear filter tuning (aQERB), a tuning ratio was derived from available BM IR measurements in animals. Results for 11 normal-hearing subjects yielded BM IR duration estimates of 37.4/F ms at 65 dB peSPL and 36.4/F ms at 71 dB peSPL, with F in kHz. Corresponding QERB estimates were 14.2F[in kHz]0.22 at 65 dB peSPL and 13.8F[in kHz]0.22 at 71 dB peSPL. Because the proposed temporal suppression method relies on cochlear nonlinearity, the method is applicable for stimulus levels above 30–40 dB SPL and complements existing OAE methods to assess human cochlear filter tuning.
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Plastic Changes along Auditory Pathway during Salicylate-Induced Ototoxicity: Hyperactivity and CF Shifts
Source:Hearing Research
Author(s): Chen Jiang, Bin Luo, Senthilvelan Manohar, Guang-Di Chen, Richard Salvi
High dose of salicylate, the active ingredient in aspirin, has long been known to induce transient hearing loss, tinnitus and hyperacusis making it a powerful experimental tool. These salicylate-induced perceptual disturbances are associated with a massive reduction in the neural output of the cochlea. Paradoxically, the diminished neural output of the cochlea is accompanied by a dramatic increase in sound-evoked activity in the auditory cortex (AC) and several other parts of the central nervous system. Exactly where the increase in neural activity begins and builds up along the central auditory pathway are not fully understood. To address this issue, we measured sound-evoked neural activity in the cochlea, cochlear nucleus (CN), inferior colliculus (IC), and AC before and after administering a high dose of sodium salicylate (SS, 300 mg/kg). The SS-treatment abolished low-level sound-evoked responses along the auditory pathway resulting in a 20-30 dB threshold shift. While the neural output of the cochlea was substantially reduced at high intensities, the neural responses in the CN were only slightly reduced; those in the IC were nearly normal or slightly enhanced while those in the AC considerably enhanced, indicative of a progress increase in central gain. The SS-induced increase in central response in the IC and AC was frequency-dependent with the greatest increase occurring in the mid-frequency range the putative pitch of SS-induced tinnitus. This frequency-dependent hyperactivity appeared to result from shifts in the frequency receptive fields (FRF) such that the response areas of many FRF shifted/expanded toward the mid-frequencies. Our results suggest that the SS-induced threshold shift originates in the cochlea. In contrast, enhanced central gain is not localized to one region, but progressively builds up at successively higher stage of the auditory pathway either through a loss of inhibition and/or increased excitation.
Graphical abstract
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Impulsive Noise: A Brief Review
Source:Hearing Research
Author(s): Rickie R. Davis, Odile Clavier
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The Effect of Sensorineural Hearing Loss and Tinnitus on Speech Recognition over Air and Bone Conduction Military Communications Headsets
Source:Hearing Research
Author(s): Candice Manning, Timothy Mermagen, Angelique Scharine
Military personnel are at risk for hearing loss due to noise exposure during deployment (USACHPPM, 2008). Despite mandated use of hearing protection, hearing loss and tinnitus are prevalent due to reluctance to use hearing protection. Bone conduction headsets can offer good speech intelligibility for normal hearing (NH)1 listeners while allowing the ears to remain open in quiet environments and the use of hearing protection when needed. Those who suffer from tinnitus, the experience of perceiving a sound not produced by an external source, often show degraded speech recognition; however, it is unclear whether this is a result of decreased hearing sensitivity or increased distractibility (Moon et al., 2015). It has been suggested that the vibratory stimulation of a bone conduction headset might ameliorate the effects of tinnitus on speech perception; however, there is currently no research to support or refute this claim (Hoare et al., 2014). Speech recognition of words presented over air conduction and bone conduction headsets was measured for three groups of listeners: NH, sensorineural hearing impaired, and/or tinnitus sufferers. Three levels of speech-to-noise (SNR=0,-6,-12 dB) were created by embedding speech items in pink noise. Better speech recognition performance was observed with the bone conduction headset regardless of hearing profile, and speech intelligibility was a function of SNR. Discussion will include study limitations and the implications of these findings for those serving in the military.
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Effects of long-term non-traumatic noise exposure on the adult central auditory system. Hearing problems without hearing loss
Source:Hearing Research
Author(s): Jos J. Eggermont
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 hearing loss. The central effects for these moderate level exposures described in this review include changes in central gain, increased spontaneous firing rates and neural synchrony, and reorganization of the cortical tonotopic map. A putative mechanism is outlined, and the effect of the acoustic environment during the recovery process is illustrated. Parallels are drawn with hearing problems in humans with long-duration exposures to occupational noise but with clinical normal hearing.
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