JARO - Journal of the Association for Research in Otolaryngology 
This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.
This is an RSS file. You can use it to subscribe to this data in your favourite RSS reader or to display this data on your own website or blog.Expression and Neurotransmitter Association of the Synaptic Calcium Sensor Synaptotagmin in the Avian Auditory Brain Stem
AbstractIn the avian auditory brain stem, acoustic timing and intensity cues are processed in separate, parallel pathways via the two divisions of the cochlear nucleus, nucleus angularis (NA) and nucleus magnocellularis (NM). Differences in excitatory and inhibitory synaptic properties, such as release probability and short-term plasticity, contribute to differential processing of the auditory nerve inputs. We investigated the distribution of synaptotagmin, a putative calcium sensor for exocytosis, via immunohistochemistry and double immunofluorescence in the embryonic and hatchling chick brain stem (Gallus gallus). We fou...
Source: JARO - Journal of the Association for Research in Otolaryngology - August 23, 2022 Category: ENT & OMF Source Type: research
Could Tailored Chirp Stimuli Benefit Measurement of the Supra-threshold Auditory Brainstem Wave-I Response?
This study aimed to test previous claims that ABR latency dispersion differs between waves I and V, and between males and females, and thus that using wave- and/or sex-tailored chirps may provide more reliable wave-I benefit . Using the derived-band technique, we measured responses from frequency-restricted (one-octave-wide) cochlear regions to energy-matched click and chirp stimuli. The derived-band responses’ latencies were used to assess any wave- and/or sex-related dispersion differences across bands, and their am plitudes, to evaluate any within-band dispersion differences. Our results suggest that sex-related dispe...
Source: JARO - Journal of the Association for Research in Otolaryngology - August 19, 2022 Category: ENT & OMF Source Type: research
Changes in the Electrically Evoked Compound Action Potential over time After Implantation and Subsequent Deafening in Guinea Pigs
AbstractThe electrically evoked compound action potential (eCAP) is a direct measure of the responsiveness of the auditory nerve to electrical stimulation from a cochlear implant (CI). CIs offer a unique opportunity to study the auditory nerve ’s electrophysiological behavior in individual human subjects over time. In order to understand exactly how the eCAP relates to the condition of the auditory nerve, it is crucial to compare changes in the eCAP over time in a controlled model of deafness-induced auditory nerve degeneration. In the present study, 10 normal-hearing young adult guinea pigs were implanted and deafened 4...
Source: JARO - Journal of the Association for Research in Otolaryngology - August 10, 2022 Category: ENT & OMF Source Type: research
Rate Discrimination Training May Partially Restore Temporal Processing Abilities from Age-Related Deficits
This study’s purpose was to evaluate the effects of rate d iscrimination training on auditory temporal processing. A double-blind, randomized control design assigned 77 young normal-hearing, older normal-hearing, and older hearing-impaired listeners to one of two treatment groups: experimental (rate discrimination for 100- and 300-Hz pulse trains) and activ e control (tone detection in noise). All listeners were evaluated during pre- and post-training sessions using perceptual rate discrimination of 100-, 200-, 300-, and 400-Hz band-limited pulse trains and auditory steady-state responses (ASSRs) to the same stimuli. Tra...
Source: JARO - Journal of the Association for Research in Otolaryngology - August 10, 2022 Category: ENT & OMF Source Type: research
Temporal Envelope Coding of the Human Auditory Nerve Inferred from Electrocochleography: Comparison with Envelope Following Responses
AbstractNeural coding of the slow amplitude fluctuations of sound (i.e., temporal envelope) is thought to be essential for speech understanding; however, such coding by the human auditory nerve is poorly understood. Here, neural coding of the temporal envelope by the human auditory nerve is inferred from measurements of the compound action potential in response to an amplitude modulated carrier (CAPENV) for modulation frequencies ranging from 20 to 1000 Hz. The envelope following response (EFR) was measured simultaneously with CAPENV from active electrodes placed on the high forehead and tympanic membrane, respectively. ...
Source: JARO - Journal of the Association for Research in Otolaryngology - August 10, 2022 Category: ENT & OMF Source Type: research
Stimulation Rate and Voice Pitch Perception in Cochlear Implants
We describe two experiments with 16 Nu cleus® CI users, where we controlled modulation characteristics and carrier rate using Spectral and Temporal Enhanced Processing (STEP), a novel experimental multichannel sound coder. We used a fixed set of threshold and comfortable stimulation levels for each subject, obtained from clinical MAPs. In the first experiment, we determined equivalence for voice pitch ranking and voice gender categorization between the Advanced Combination Encoder (ACE), a widely used clinical strategy in Nucleus® recipients, and STEP for fundamental frequencies (F0) 120–250 Hz. In the second experime...
Source: JARO - Journal of the Association for Research in Otolaryngology - August 2, 2022 Category: ENT & OMF Source Type: research
Mitigation of Hearing Damage After Repeated Blast Exposures in Animal Model of Chinchilla
This study bridges the gap between TBI and hearing impairment and suggests a possible interven tion for blast-induced hearing loss for Service members. (Source: JARO - Journal of the Association for Research in Otolaryngology)
Source: JARO - Journal of the Association for Research in Otolaryngology - July 29, 2022 Category: ENT & OMF Source Type: research
No Reduction in the 226-Hz Probe Tone Acoustic Reflex Amplitude Following Severe Inner Hair Cell Loss in Chinchillas
AbstractThe relationship between the middle ear acoustic reflex (AR) and inner hair cell (IHC) loss is currently unknown. Given that IHC are believed to convey nearly all acoustic information to the central auditory nervous system, it has been assumed that loss of IHC would significantly impact the AR. To evaluate this relationship, we assessed the presence and amplitude of the AR in chinchillas before and after treatment with carboplatin, an anticancer drug that reliably and selectively destroys IHC in this species. Baseline measures of hearing sensitivity, including auditory brainstem response (ABR) thresholds and distor...
Source: JARO - Journal of the Association for Research in Otolaryngology - July 28, 2022 Category: ENT & OMF Source Type: research
Physiological Evidence for Delayed Age-related Hearing Loss in Two Long-lived Rodent Species (Peromyscus leucopus and P. californicus)
AbstractDeer mice (genusPeromyscus) are an emerging model for aging studies due to their longevity relative to rodents of similar size. AlthoughPeromyscus species are well-represented in genetic, developmental, and behavioral studies, relatively few studies have investigated auditory sensitivity in this genus. Given the potential utility ofPeromyscus for investigations of age-related changes to auditory function, we recorded auditory brainstem responses (ABRs) in twoPeromyscus species,P. californicus, andP. leucopus, across the lifespan. We compared hearing sensitivity and ABR wave metrics measured in these species with me...
Source: JARO - Journal of the Association for Research in Otolaryngology - July 26, 2022 Category: ENT & OMF Source Type: research
Insights into Inner Ear Function and Disease Through Novel Visualization of the Ductus Reuniens, a Seminal Communication Between Hearing and Balance Mechanisms
AbstractThe sensory end-organs responsible for hearing and balance in the mammalian inner ear are connected via a small membranous duct known as the ductus reuniens (also known as the reuniting duct (DR)). The DR serves as a vital nexus linking the hearing and balance systems by providing the only endolymphatic connection between the cochlea and vestibular labyrinth. Recent studies have hypothesized new roles of the DR in inner ear function and disease, but a lack of knowledge regarding its 3D morphology and spatial configuration precludes testing of such hypotheses. We reconstructed the 3D morphology of the DR and surroun...
Source: JARO - Journal of the Association for Research in Otolaryngology - July 8, 2022 Category: ENT & OMF Source Type: research
Characterizing the Relationship Between Reflection and Distortion Otoacoustic Emissions in Normal-Hearing Adults
AbstractOtoacoustic emissions (OAEs) arise from one (or a combination) of two basic generation mechanisms in the cochlea: nonlinear distortion and linear reflection. As a result of having distinct generation processes, these two classes of emissions may provide non-redundant information about hair-cell integrity and show distinct sensitivities to cochlear pathology. Here, we characterize the relationship between reflection and distortion emissions in normal hearers across a broad frequency and stimulus-level space using novel analysis techniques. Furthermore, we illustrate the promise of this approach in a small group of i...
Source: JARO - Journal of the Association for Research in Otolaryngology - July 8, 2022 Category: ENT & OMF Source Type: research
Sound Induced Vibrations Deform the Organ of Corti Complex in the Low-Frequency Apical Region of the Gerbil Cochlea for Normal Hearing
AbstractHuman speech primarily contains low frequencies. It is well established that such frequencies maximally excite the cochlea near its apex. But, the micromechanics that precede and are involved in this transduction are not well understood. We measured vibrations from the low-frequency, second turn in intact gerbil cochleae using optical coherence tomography (OCT). The data were used to create spatial maps that detail the sound-evoked motions across the sensory organ of Corti complex (OCC). These maps were remarkably similar across animals and showed little variation with frequency or level. We identify four, anatomic...
Source: JARO - Journal of the Association for Research in Otolaryngology - July 7, 2022 Category: ENT & OMF Source Type: research
How Peripheral Vestibular Damage Affects Velocity Storage: a Causative Explanation
AbstractVelocity storage is a centrally-mediated mechanism that processes peripheral vestibular inputs. One prominent aspect of velocity storage is its effect on dynamic responses to yaw rotation. Specifically, when normal human subjects are accelerated to constant angular yaw velocity, horizontal eye movements and perceived angular velocity decay exponentially with a time constant circa 15 –30 s, even though the input from the vestibular periphery decays much faster (~ 6 s). Peripheral vestibular damage causes a time constant reduction, which is useful for clinical diagnoses, but a mechanistic explanation for the re...
Source: JARO - Journal of the Association for Research in Otolaryngology - June 29, 2022 Category: ENT & OMF Source Type: research
Tonotopic Selectivity in Cats and Humans: Electrophysiology and Psychophysics
We describe a scalp-recorded measure of tonotopic selectivity, the “cortical onset response” (COR) and compare the results between humans and cats. The COR results, in turn, were compared with psychophysical masked-detection thresholds obtained using similar stimuli and obtained from both species. The COR consisted of averaged responses elicited by 50-ms tone-b urst probes presented at 1-s intervals against a continuous noise masker. The noise masker had a bandwidth of 1 or 1/8th octave, geometrically centred on 4000 Hz for humans and on 8000 Hz for cats. The probe frequency was either − 0.5, − 0.25, 0, 0...
Source: JARO - Journal of the Association for Research in Otolaryngology - June 13, 2022 Category: ENT & OMF Source Type: research
Temporal Pitch Sensitivity in an Animal Model: Psychophysics and Scalp Recordings
AbstractCochlear implant (CI) users show limited sensitivity to the temporal pitch conveyed by electric stimulation, contributing to impaired perception of music and of speech in noise. Neurophysiological studies in cats suggest that this limitation is due, in part, to poor transmission of the temporal fine structure (TFS) by the brainstem pathways that are activated by electrical cochlear stimulation. It remains unknown, however, how that neural limit might influence perception in the same animal model. For that reason, we developed non-invasive psychophysical and electrophysiological measures of temporal (i.e., non-spect...
Source: JARO - Journal of the Association for Research in Otolaryngology - June 6, 2022 Category: ENT & OMF Source Type: research
