Individual similarities and differences in eye-movement-related eardrum oscillations (EMREOs)
Hear Res. 2023 Oct 30;440:108899. doi: 10.1016/j.heares.2023.108899. Online ahead of print.ABSTRACTWe recently discovered a unique type of otoacoustic emission (OAE) time-locked to the onset (and offset) of saccadic eye movements and occurring in the absence of external sound (Gruters et al., 2018). How and why these eye-movement-related eardrum oscillations (EMREOs) are generated is unknown, with a role in visual-auditory integration being the likeliest candidate. Clues to both the drivers of EMREOs and their purpose can be gleaned by examining responses in normal hearing human subjects. Do EMREOs occur in all individuals...
Source: Hearing Research - November 18, 2023 Category: Audiology Authors: Cynthia D King Stephanie N Lovich David Lk Murphy Rachel Landrum David Kaylie Christopher A Shera Jennifer M Groh Source Type: research

Spread of activation and interaction between channels with multi-channel optogenetic stimulation in the mouse cochlea
This study compares the spread of neural activity across the inferior colliculus of the auditory midbrain during electrical and optical stimulation in the cochlea of acutely deafened mice with opsin-modified spiral ganglion neurons (H134R variant of the channelrhodopsin-2). Monopolar electrical stimulation was delivered via each of four 0.2 mm wide platinum electrode rings at 0.6 mm centre-to-centre spacing, whereas 453 nm wavelength light was delivered via each of five 0.22 × 0.27 mm micro-light emitting diodes (LEDs) at 0.52 mm centre-to-centre spacing. Channel interactions were also quantified by threshold changes duri...
Source: Hearing Research - November 17, 2023 Category: Audiology Authors: Ajmal A Azees Alex C Thompson Ross Thomas Jenny Zhou Patrick Ruther Andrew K Wise Elise A Ajay David J Garrett Anita Quigley James B Fallon Rachael T Richardson Source Type: research

Spread of activation and interaction between channels with multi-channel optogenetic stimulation in the mouse cochlea
This study compares the spread of neural activity across the inferior colliculus of the auditory midbrain during electrical and optical stimulation in the cochlea of acutely deafened mice with opsin-modified spiral ganglion neurons (H134R variant of the channelrhodopsin-2). Monopolar electrical stimulation was delivered via each of four 0.2 mm wide platinum electrode rings at 0.6 mm centre-to-centre spacing, whereas 453 nm wavelength light was delivered via each of five 0.22 × 0.27 mm micro-light emitting diodes (LEDs) at 0.52 mm centre-to-centre spacing. Channel interactions were also quantified by threshold changes duri...
Source: Hearing Research - November 17, 2023 Category: Audiology Authors: Ajmal A Azees Alex C Thompson Ross Thomas Jenny Zhou Patrick Ruther Andrew K Wise Elise A Ajay David J Garrett Anita Quigley James B Fallon Rachael T Richardson Source Type: research

Susceptibility of immature spiral ganglion neurons to aminoglycoside-induced ototoxicity is mediated by the TRPV1 channel in mice
This study aimed to investigate whether a nonselective cation channel, TRPV1, contributes to the susceptibility of immature spiral ganglion neurons (SGNs) to the damage caused by aminoglycosides. Through western blotting and immunofluorescence, we found that the TRPV1 expression levels were much higher in immature SGNs than in their mature counterparts. In postnatal day 7 cochlear organotypic cultures, AMG-517 reduced reactive oxygen species generation and inhibited SGN apoptosis under aminoglycoside challenge. However, in adult mice, AMG-517 did not ameliorate the ABR threshold increase at high frequencies (16 kHz and 32 ...
Source: Hearing Research - November 13, 2023 Category: Audiology Authors: Yijiang Bai Jing Liu Xuewen Wu Bo Pang Shuai Zhang Mengzhu Jiang Anhai Chen Huping Huang Yongjia Chen Yuan Zeng Lingyun Mei Kelei Gao Source Type: research

Susceptibility of immature spiral ganglion neurons to aminoglycoside-induced ototoxicity is mediated by the TRPV1 channel in mice
This study aimed to investigate whether a nonselective cation channel, TRPV1, contributes to the susceptibility of immature spiral ganglion neurons (SGNs) to the damage caused by aminoglycosides. Through western blotting and immunofluorescence, we found that the TRPV1 expression levels were much higher in immature SGNs than in their mature counterparts. In postnatal day 7 cochlear organotypic cultures, AMG-517 reduced reactive oxygen species generation and inhibited SGN apoptosis under aminoglycoside challenge. However, in adult mice, AMG-517 did not ameliorate the ABR threshold increase at high frequencies (16 kHz and 32 ...
Source: Hearing Research - November 13, 2023 Category: Audiology Authors: Yijiang Bai Jing Liu Xuewen Wu Bo Pang Shuai Zhang Mengzhu Jiang Anhai Chen Huping Huang Yongjia Chen Yuan Zeng Lingyun Mei Kelei Gao Source Type: research

Susceptibility of immature spiral ganglion neurons to aminoglycoside-induced ototoxicity is mediated by the TRPV1 channel in mice
This study aimed to investigate whether a nonselective cation channel, TRPV1, contributes to the susceptibility of immature spiral ganglion neurons (SGNs) to the damage caused by aminoglycosides. Through western blotting and immunofluorescence, we found that the TRPV1 expression levels were much higher in immature SGNs than in their mature counterparts. In postnatal day 7 cochlear organotypic cultures, AMG-517 reduced reactive oxygen species generation and inhibited SGN apoptosis under aminoglycoside challenge. However, in adult mice, AMG-517 did not ameliorate the ABR threshold increase at high frequencies (16 kHz and 32 ...
Source: Hearing Research - November 13, 2023 Category: Audiology Authors: Yijiang Bai Jing Liu Xuewen Wu Bo Pang Shuai Zhang Mengzhu Jiang Anhai Chen Huping Huang Yongjia Chen Yuan Zeng Lingyun Mei Kelei Gao Source Type: research

Susceptibility of immature spiral ganglion neurons to aminoglycoside-induced ototoxicity is mediated by the TRPV1 channel in mice
This study aimed to investigate whether a nonselective cation channel, TRPV1, contributes to the susceptibility of immature spiral ganglion neurons (SGNs) to the damage caused by aminoglycosides. Through western blotting and immunofluorescence, we found that the TRPV1 expression levels were much higher in immature SGNs than in their mature counterparts. In postnatal day 7 cochlear organotypic cultures, AMG-517 reduced reactive oxygen species generation and inhibited SGN apoptosis under aminoglycoside challenge. However, in adult mice, AMG-517 did not ameliorate the ABR threshold increase at high frequencies (16 kHz and 32 ...
Source: Hearing Research - November 13, 2023 Category: Audiology Authors: Yijiang Bai Jing Liu Xuewen Wu Bo Pang Shuai Zhang Mengzhu Jiang Anhai Chen Huping Huang Yongjia Chen Yuan Zeng Lingyun Mei Kelei Gao Source Type: research

Sound externalization in dynamic binaural listening: A comparative behavioral and EEG study
Hear Res. 2023 Nov 8;440:108912. doi: 10.1016/j.heares.2023.108912. Online ahead of print.ABSTRACTBinaural reproduction aims at recreating a realistic sound scene at the ears of the listener using headphones. Unfortunately, externalization for frontal and rear sources is often poor (virtual sources are perceived inside the head, instead of outside the head). Nevertheless, previous studies have shown that large head-tracked movements could substantially improve externalization and that this improvement persisted once the subject had stopped moving his/her head. The present study investigates the relation between externaliza...
Source: Hearing Research - November 12, 2023 Category: Audiology Authors: Tom Colas Nicolas Farrugia Etienne Hendrickx Mathieu Paquier Source Type: research

From the outer ear to the nerve: A complete computer model of the peripheral auditory system
Hear Res. 2023 Oct 31;440:108900. doi: 10.1016/j.heares.2023.108900. Online ahead of print.ABSTRACTComputer models of the individual components of the peripheral auditory system - the outer, middle, and inner ears and the auditory nerve - have been developed in the past, with varying level of detail, breadth, and faithfulness of the underlying parameters. Building on previous work, we advance the modeling of the ear by presenting a complete, physiologically justified, bottom-up computer model based on up-to-date experimental data that integrates all of these parts together seamlessly. The detailed bottom-up design of the p...
Source: Hearing Research - November 9, 2023 Category: Audiology Authors: Ondrej Tichacek Pavel Mistr ík Pavel Jungwirth Source Type: research

From the outer ear to the nerve: A complete computer model of the peripheral auditory system
Hear Res. 2023 Oct 31;440:108900. doi: 10.1016/j.heares.2023.108900. Online ahead of print.ABSTRACTComputer models of the individual components of the peripheral auditory system - the outer, middle, and inner ears and the auditory nerve - have been developed in the past, with varying level of detail, breadth, and faithfulness of the underlying parameters. Building on previous work, we advance the modeling of the ear by presenting a complete, physiologically justified, bottom-up computer model based on up-to-date experimental data that integrates all of these parts together seamlessly. The detailed bottom-up design of the p...
Source: Hearing Research - November 9, 2023 Category: Audiology Authors: Ondrej Tichacek Pavel Mistr ík Pavel Jungwirth Source Type: research

From the outer ear to the nerve: A complete computer model of the peripheral auditory system
Hear Res. 2023 Oct 31;440:108900. doi: 10.1016/j.heares.2023.108900. Online ahead of print.ABSTRACTComputer models of the individual components of the peripheral auditory system - the outer, middle, and inner ears and the auditory nerve - have been developed in the past, with varying level of detail, breadth, and faithfulness of the underlying parameters. Building on previous work, we advance the modeling of the ear by presenting a complete, physiologically justified, bottom-up computer model based on up-to-date experimental data that integrates all of these parts together seamlessly. The detailed bottom-up design of the p...
Source: Hearing Research - November 9, 2023 Category: Audiology Authors: Ondrej Tichacek Pavel Mistr ík Pavel Jungwirth Source Type: research

From the outer ear to the nerve: A complete computer model of the peripheral auditory system
Hear Res. 2023 Oct 31;440:108900. doi: 10.1016/j.heares.2023.108900. Online ahead of print.ABSTRACTComputer models of the individual components of the peripheral auditory system - the outer, middle, and inner ears and the auditory nerve - have been developed in the past, with varying level of detail, breadth, and faithfulness of the underlying parameters. Building on previous work, we advance the modeling of the ear by presenting a complete, physiologically justified, bottom-up computer model based on up-to-date experimental data that integrates all of these parts together seamlessly. The detailed bottom-up design of the p...
Source: Hearing Research - November 9, 2023 Category: Audiology Authors: Ondrej Tichacek Pavel Mistr ík Pavel Jungwirth Source Type: research

Cochlear metabolomics, highlighting novel insights of purine metabolic alterations in age-related hearing loss
In this study, mean thresholds of auditory brainstem responses (ABR) and distortion-product otoacoustic emissions (DPOAE) increased at multiple frequencies in aged rats (14 months old) compared to young rats (2 months old). Using untargeted ultra-high performance liquid chromatography-mass spectroscopy (LC-MS), we quantified molecular metabolic markers in the cochlea of aged rats with hearing loss. A total of 137 different metabolites were identified in two groups, highlighting several prominent metabolic pathways related to purine metabolism; glycine, serine, and threonine metabolism; arginine and proline metabolism; and ...
Source: Hearing Research - November 8, 2023 Category: Audiology Authors: Huanzhi Wan Wenjing Wang Jingchun Liu Yunlong Zhang Bingqian Yang Rongkai Hua Huidong Chen Shiming Chen Qingquan Hua Source Type: research

Investigating the optimal stimulus to evoke the binaural interaction component of the auditory brainstem response
This study aims to improve ABR BIC measurements by determining more optimal stimuli to evoke it. Building on previous methodology demonstrated to enhance peak amplitude of monaural ABRs, we constructed a series of level-dependent chirp stimuli based on empirically derived latencies of monaural-evoked ABR waves I, IV and the binaural-evoked BIC DN1, the most prominent BIC peak, in a cohort of ten chinchillas. We hypothesized that chirps designed based on BIC DN1 latency would specifically enhance across-frequency temporal synchrony in the afferent inputs leading to the binaural circuits that produce the BIC and would thus p...
Source: Hearing Research - November 4, 2023 Category: Audiology Authors: Zoe L Owrutsky John Peacock Daniel J Tollin Source Type: research

Investigating the optimal stimulus to evoke the binaural interaction component of the auditory brainstem response
This study aims to improve ABR BIC measurements by determining more optimal stimuli to evoke it. Building on previous methodology demonstrated to enhance peak amplitude of monaural ABRs, we constructed a series of level-dependent chirp stimuli based on empirically derived latencies of monaural-evoked ABR waves I, IV and the binaural-evoked BIC DN1, the most prominent BIC peak, in a cohort of ten chinchillas. We hypothesized that chirps designed based on BIC DN1 latency would specifically enhance across-frequency temporal synchrony in the afferent inputs leading to the binaural circuits that produce the BIC and would thus p...
Source: Hearing Research - November 4, 2023 Category: Audiology Authors: Zoe L Owrutsky John Peacock Daniel J Tollin Source Type: research