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.

Using Spectral Blurring to Assess Effects of Channel Interaction on Speech-in-Noise Perception with Cochlear Implants
AbstractCochlear implant (CI) listeners struggle to understand speech in background noise. Interactions between electrode channels due to current spread increase the masking of speech by noise and lead to difficulties with speech perception. Strategies that reduce channel interaction therefore have the potential to improve speech-in-noise perception by CI listeners, but previous results have been mixed. We investigated the effects of channel interaction on speech-in-noise perception and its association with spectro-temporal acuity in a listening study with 12 experienced CI users. Instead of attempting to reduce channel in...
Source: JARO - Journal of the Association for Research in Otolaryngology - June 8, 2020 Category: ENT & OMF Source Type: research

Effects of Gap Position on Perceptual Gap Detection Across Late Childhood and Adolescence
AbstractThe ability to detect a silent gap within a sound is critical for accurate speech perception, and gap detection has been shown to have an extended developmental trajectory. In certain conditions, the detectability of the gap decreases as the gap is placed closer to the beginning of the signal. Early in development, the detection of gaps shortly after signal onset may be especially difficult due to immaturities in the encoding and perception of rapidly changing sounds. The present study explored the development of gap detection from age 8 to 19  years, specifically when the temporal placement of the gap varied. Per...
Source: JARO - Journal of the Association for Research in Otolaryngology - June 1, 2020 Category: ENT & OMF Source Type: research

Information Processing by Onset Neurons in the Cat Auditory Brainstem
We examined responses of neurons in the ventral nucleus of the lateral lemniscus (VNLL) whose dischar ges to tones and AM sounds are similar to octopus cells. Repeated stimulation with short tone pips of VCN and VNLL onset neurons evokes trains of action potentials with gradual shifts toward later times in their first spike latency. This behavior parallels short-term post-synaptic depression observe d by other authors in in vitro VCN recordings of octopus cells. VCN and VNLL onset units in cats respond to frozen noise stimuli with gaps as narrow as 1 ms with a robust discharge near the stimulus onset following the gap. Th...
Source: JARO - Journal of the Association for Research in Otolaryngology - May 25, 2020 Category: ENT & OMF Source Type: research

Correction to: The Developing Concept of Tonotopic Organization of the Inner Ear
The email address for Robert J. Ruben should be rruben@montefiore.org (Source: JARO - Journal of the Association for Research in Otolaryngology)
Source: JARO - Journal of the Association for Research in Otolaryngology - May 5, 2020 Category: ENT & OMF Source Type: research

Effects of Electrode Location on Estimates of Neural Health in Humans with Cochlear Implants
AbstractThere are a number of psychophysical and electrophysiological measures that are correlated with SGN density in animal models, and these same measures can be performed in humans with cochlear implants (CIs). Thus, these measures are potentially applicable in humans for estimating the condition of the neural population (so called “neural health” or “cochlear health”) at individual sites along the electrode array and possibly adjusting the stimulation strategy in the CI sound processor accordingly. Some measures used to estimate neural health in animals have included the electrically evoked compound potential ...
Source: JARO - Journal of the Association for Research in Otolaryngology - April 26, 2020 Category: ENT & OMF Source Type: research

Noise-Induced Changes of the Auditory Brainstem Response to Speech —a Measure of Neural Desynchronisation?
AbstractIt is commonly assumed that difficulty in listening to speech in noise is at least partly due to deficits in neural temporal processing. Given that noise reduces the temporal fidelity of the auditory brainstem response (ABR) to speech, it has been suggested that the speech ABR may serve as an index of such neural deficits. However, the temporal fidelity of ABRs, to both speech and non-speech sounds, is also known to be influenced by the cochlear origin of the response, as responses from higher-frequency cochlear regions are faster and more synchronous than responses from lower-frequency regions. Thus, if noise caus...
Source: JARO - Journal of the Association for Research in Otolaryngology - April 12, 2020 Category: ENT & OMF Source Type: research

Retinal Image Slip Must Pass the Threshold for Human Vestibulo-Ocular Reflex Adaptation
AbstractWe sought to determine whether repeated vestibulo-ocular reflex (VOR) adaptation training to increase the VOR gain (eye/head velocity) had a lasting effect in normal subjects and whether there was a retinal image slip tolerance threshold for VOR adaptation. We used the unilateral incremental VOR adaptation technique and horizontal active (self-generated, predictable) head impulses as the vestibular stimulus. Both active and passive (imposed, unpredictable) head impulse VOR gains were measured before and after unilateral incremental VOR adaptation training. The adapting side was pseudo-randomized for left or right. ...
Source: JARO - Journal of the Association for Research in Otolaryngology - March 29, 2020 Category: ENT & OMF Source Type: research

Asymmetry and Microstructure of Temporal-Suppression Patterns in Basilar-Membrane Responses to Clicks: Relation to Tonal Suppression and Traveling-Wave Dispersion
AbstractThe cochlea ’s wave-based signal processing allows it to efficiently decompose a complex acoustic waveform into frequency components. Because cochlear responses are nonlinear, the waves arising from one frequency component of a complex sound can be altered by the presence of others that overlap with it in tim e and space (e.g., two-tone suppression). Here, we investigate the suppression of basilar-membrane (BM) velocity responses to a transient signal (a test click) by another click or tone. We show that the BM response to the click can be reduced when the stimulus is shortly preceded or followed by anot her (sup...
Source: JARO - Journal of the Association for Research in Otolaryngology - March 11, 2020 Category: ENT & OMF Source Type: research

Anatomy of the Human Osseous Spiral Lamina and Cochlear Partition Bridge: Relevance for Cochlear Partition Motion
We described a human soft tissue “bridge” (non-existent in the classic view) between the osseous spiral lamina (OSL) and basilar membrane (BM), and showed how OSL and bridge move in response to sound. Here, we detail relevant human anatomy to better understand the relationship between form and function. The bridge and BM have s imilar widths that increase linearly from base to apex, whereas the OSL width decreases from base to apex, leading to an approximately constant total CP width throughout the cochlea. The bony three-dimensional OSL microstructure, reconstructed from unconventionally thin, 2-μm histological secti...
Source: JARO - Journal of the Association for Research in Otolaryngology - March 11, 2020 Category: ENT & OMF Source Type: research

Myosin-XVa Controls Both Staircase Architecture and Diameter Gradation of Stereocilia Rows in the Auditory Hair Cell Bundles
AbstractMammalian hair cells develop their mechanosensory bundles through consecutive phases of stereocilia elongation, thickening, and retraction of supernumerary stereocilia. Many molecules involved in stereocilia elongation have been identified, including myosin-XVa. Significantly less is known about molecular mechanisms of stereocilia thickening and retraction. Here, we used scanning electron microscopy (SEM) to quantify postnatal changes in number and diameters of the auditory hair cell stereocilia inshaker-2 mice (Myo15sh2) that lack both “long” and “short” isoforms of myosin-XVa, and in mice lacking only the...
Source: JARO - Journal of the Association for Research in Otolaryngology - March 8, 2020 Category: ENT & OMF Source Type: research

Systemic Fluorescent Gentamicin Enters Neonatal Mouse Hair Cells Predominantly Through Sensory Mechanoelectrical Transduction Channels
AbstractSystemically administered aminoglycoside antibiotics can enter inner ear hair cells and trigger apoptosis. However, the in vivo route(s) by which aminoglycoside antibiotics enter hair cells remains controversial. Aminoglycosides can enter mouse hair cells by endocytosis or by permeation through transmembrane ion channels such as sensory mechanoelectrical transduction (MET) channels, transient receptor potential (TRP) channels, P2X channels, Piezo2-containing ion channels, or a combination of these routes. Transmembrane channel-like 1 (TMC1) and TMC2 are essential for sensory MET and appear to be the pore-forming co...
Source: JARO - Journal of the Association for Research in Otolaryngology - March 8, 2020 Category: ENT & OMF Source Type: research

The Perception of Multiple Simultaneous Pitches as a Function of Number of Spectral Channels and Spectral Spread in a Noise-Excited Envelope Vocoder
This study used noise-excited envelope vocoders that simulate the limited resolution of CIs to explore the perception of multiple pitches presented simultaneously. The results show that the resolution required for perceiving multiple complex pitches is comparable to that found in a previous study using single complex tones. Although relatively high performance can be achieved with 48 channels, performance remained near chance when even limited spectral spread (with filter slopes as steep as 144 dB/octave) was introduced to the simulations. Overall, these tight constraints suggest that current CI technology will not be able...
Source: JARO - Journal of the Association for Research in Otolaryngology - February 10, 2020 Category: ENT & OMF Source Type: research

Improving Interaural Time Difference Sensitivity Using Short Inter-pulse Intervals with Amplitude-Modulated Pulse Trains in Bilateral Cochlear Implants
AbstractInteraural time differences (ITDs) at low frequencies are important for sound localization and spatial speech unmasking. These ITD cues are not encoded in commonly used envelope-based stimulation strategies for cochlear implants (CIs) using high pulse rates. However, ITD sensitivity can be improved by adding extra pulses with short inter-pulse intervals (SIPIs) in unmodulated high-rate trains. Here, we investigated whether this improvement also applies to amplitude-modulated (AM) high-rate pulse trains. To this end, we systematically varied the temporal position of SIPI pulses within the envelope cycle (SIPI phase)...
Source: JARO - Journal of the Association for Research in Otolaryngology - February 9, 2020 Category: ENT & OMF Source Type: research

Polarity Sensitivity as a Potential Correlate of Neural Degeneration in Cochlear Implant Users
AbstractCochlear implant (CI) performance varies dramatically between subjects. Although the causes of this variability remain unclear, the electrode-neuron interface is thought to play an important role. Here we evaluate the contribution of two parameters of this interface on the perception of CI listeners: the electrode-to-modiolar wall distance (EMD), estimated from cone-beam computed tomography (CT) scans, and a measure of neural health. Since there is no objective way to quantify neural health in CI users, we measure stimulus polarity sensitivity, which is assumed to be related to neural degeneration, and investigate ...
Source: JARO - Journal of the Association for Research in Otolaryngology - February 3, 2020 Category: ENT & OMF Source Type: research

The Developing Concept of Tonotopic Organization of the Inner Ear
This study aims to document the historical conceptualization of the inner ear as the anatomical location for the appreciation of sound at a continuum of frequencies and to examine the evolution of concepts of tonotopic organization to our current understanding. Primary sources used are from the sixth century BCE through the twentieth century CE. Each work/reference was analyzed from two points of view: to understand the conception of hearing and the role of the inner ear and to define the main evidential method. The dependence on theory alone in the ancient world led to inaccurate conceptualization of the mechanism of hear...
Source: JARO - Journal of the Association for Research in Otolaryngology - February 3, 2020 Category: ENT & OMF Source Type: research