Hearing Research最新文献

{"title":"Ensemble responses of auditory midbrain neurons in the cat to speech stimuli at different signal-to-noise ratios","authors":"Anu Sabu ,&nbsp;Dexter Irvine ,&nbsp;David B. Grayden ,&nbsp;James Fallon","doi":"10.1016/j.heares.2024.109163","DOIUrl":"10.1016/j.heares.2024.109163","url":null,"abstract":"<div><div>Originally reserved for those who are profoundly deaf, cochlear implantation is now common for people with partial hearing loss, particularly when combined with a hearing aid. This combined intervention enhances speech comprehension and sound quality when compared to electrical stimulation alone, particularly in noisy environments, but the physiological basis for the benefits is not well understood. Our long-term aim is to elucidate the underlying physiological mechanisms of this improvement, and as a first step in this process, we have investigated in normal hearing cats, the degree to which the patterns of neural activity evoked in the inferior colliculus (IC) by speech sounds in various levels of noise allows discrimination between those sounds. Neuronal responses were recorded simultaneously from 32 sites across the tonotopic axis of the IC in anaesthetised normal hearing cats (<em>n</em> = 7). Speech sounds were presented at 20, 40 and 60 dB SPL in quiet and with increasing levels of additive noise (signal-to-noise ratios (SNRs) –20, –15, –10, –5, 0, +5, +10, +15, +20 dB). Neural discrimination was assessed using a Euclidean measure of distance between neural responses, resulting in a function reflecting speech sound differentiation across various SNRs. Responses of IC neurons reliably encoded the speech stimuli when presented in quiet, with optimal performance when an analysis bin-width of 5–10 ms was used. Discrimination thresholds did not depend on stimulus level and were best for shorter analysis binwidths. This study sheds light on how the auditory midbrain represents speech sounds and provides baseline data with which responses to electro-acoustic speech sounds in partially deafened animals can be compared.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"456 ","pages":"Article 109163"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142805591","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neural and behavioral binaural hearing impairment and its recovery following moderate noise exposure","authors":"Monica A. Benson ,&nbsp;John Peacock ,&nbsp;Matthew D. Sergison ,&nbsp;Dominik Stich ,&nbsp;Daniel J. Tollin","doi":"10.1016/j.heares.2024.109166","DOIUrl":"10.1016/j.heares.2024.109166","url":null,"abstract":"<div><div>Noise-induced cochlear synaptopathy has been studied for over 25 years with no known diagnosis for this disorder in humans. This type of “hidden hearing loss” induces a loss of synapses in the inner ear but no change in audiometric thresholds. Recent studies have shown that by two months post synaptopathy-inducing noise exposure, synapses in some animal species can regenerate. Animal studies to date have focused primarily on peripheral hearing measures to diagnose ribbon synapse loss, while suggesting binaural listening deficits such as speech-reception-in-noise result from this disorder, but haven't accounted for the possible regeneration of synapses. To address this, we measured binaural physiological and behavioral function, the latter utilizing the pre-pulse inhibition of acoustic startle method, in both male and female adult guinea pigs following exposure to noise that has been shown to induce cochlear synaptopathy. Physiological measurements extended to 2 months post noise exposure to characterize any deficit and subsequent recovery. While common audiological assessments showed temporary threshold shift, reduced evoked potential amplitudes indicative of synaptopathy and measurable binaural electrophysiological hearing deficits post exposure, all measures recovered by 2 months. Suspected regeneration of synaptic ribbons occurred by 2 months post exposure and cochlear histology revealed no synaptic loss 4 months post exposure. Our results show that the same noise exposure protocol demonstrated to cause synaptic loss in prior studies causes physiological binaural processing deficits in the brainstem and that the recovery of neural binaural processing coincides with the regeneration of synapses shown in previous studies and normal binaural hearing behavior.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"456 ","pages":"Article 109166"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142853084","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Auditory working memory in noise in cochlear implant users: Insights from behavioural and neuronal measures","authors":"Loes Beckers ,&nbsp;Birgit Philips ,&nbsp;Wendy Huinck ,&nbsp;Emmanuel Mylanus ,&nbsp;Andreas Büchner ,&nbsp;Andrej Kral","doi":"10.1016/j.heares.2024.109167","DOIUrl":"10.1016/j.heares.2024.109167","url":null,"abstract":"<div><h3>Objective</h3><div>We investigated auditory working-memory using behavioural measures and electroencephalography (EEG) in adult Cochlear Implant (CI) users with varying degrees of CI performance.</div></div><div><h3>Methods</h3><div>24 adult CI listeners (age: M = 61.38, SD = 12.45) performed the Sternberg auditory-digit-in-working-memory task during which EEG, accuracy, and promptness were captured. Participants were presented with 2, 4, or 6 digits at Signal-to-Noise Ratios (SNR) of 0, +5 and +10dB. They had to identify a probe stimulus as present in the preceding sequence. ANOVA models were used to compare conditions.</div></div><div><h3>Results</h3><div>ANOVA revealed that increasing memory load (ML) led to decreased task performance and CI performance interacted with ML and SNR. Centro-parietal alpha power increased during memory encoding but did not differ between conditions. Frontal alpha power was positively correlated with accuracy in conditions most affected by SNR (<em>r</em> = 0.57, <em>r</em> = 0.52) and theta power in conditions most affected by ML (<em>r</em> = 0.55, <em>r</em> = 0.57).</div></div><div><h3>Conclusions</h3><div>While parietal alpha power is modulated by the task, it is frontal alpha that relates quantitatively to sensory aspects of processing (noise) and frontal theta to memory load in this group of CI listeners.</div></div><div><h3>Significance</h3><div>These results suggest that alpha and theta show distinct relationships to behaviour, providing additional insight into neurocognitive (auditory working-memory) processes in CI users.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"456 ","pages":"Article 109167"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142884808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the impact of force direction and phase on bone conduction hearing with bone conduction actuator","authors":"Jongwoo Lim ,&nbsp;Namkeun Kim ,&nbsp;Yong-Jin Yoon","doi":"10.1016/j.heares.2024.109164","DOIUrl":"10.1016/j.heares.2024.109164","url":null,"abstract":"<div><div>A comprehensive understanding of the effects of bone conduction (BC) input force is essential for elucidating BC hearing mechanisms. However, this area remains underexplored due to the inherent difficulties in controlling input forces when BC transducers are anchored to the bone. In this study, the effects of both unilateral and bilateral BC input forces were investigated using a three-dimensional finite element (FE) model of the human head, which allows precise manipulation of input forces. For unilateral input, 16 distinct directions were created by combining eight in-plane vectors with two tilt angles based on the normal direction of the input force location, and the resulting promontory velocities were compared. Although the magnitude differences between input directions remained within 10 dB, anti-resonance shifts were observed between 1 and 3 kHz. In the bilateral case, phase differences of 0°, 90°, and 180° were applied between input forces at the right and left mastoid positions, and basilar membrane velocities were compared to examine the complex interactions between input forces. These findings provide deeper insights into the effects of input force direction and phase on BC hearing, advancing the understanding of BC hearing mechanisms.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"456 ","pages":"Article 109164"},"PeriodicalIF":2.5,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142823972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tinnitus, lucid dreaming and awakening. An online survey and theoretical implications.","authors":"Robin Guillard ,&nbsp;Nicolas Dauman ,&nbsp;Aurélien Cadix ,&nbsp;Charlotte Glabasnia Linck ,&nbsp;Marco Congedo ,&nbsp;Dirk De Ridder ,&nbsp;Alain Londero","doi":"10.1016/j.heares.2025.109204","DOIUrl":"10.1016/j.heares.2025.109204","url":null,"abstract":"<div><h3>Background</h3><div>Tinnitus is the perception of phantom sound in the absence of a corresponding external source. Previous studies reported that the presence of tinnitus is notably absent during dreams. This study aimed at replicating previous findings regarding tinnitus-free dreams, while also gaining a deeper understanding of tinnitus manifestations during dreams and after awakening.</div></div><div><h3>Methods</h3><div>For this observational study, 195 tinnitus patients answered an online survey on the mutual-help community Siopi.</div></div><div><h3>Results</h3><div>148 subjective tinnitus patients could recall their dreams. Among them, 94.6 % state they do not hear their tinnitus while dreaming. The rest (5.4 %) report higher tinnitus burden, higher stress and more often exhibit cophosis, tinnitus related to peripheral auditory pathology and/or associated with other health comorbidities. 12.2 % of the participants frequently experience lucid dreams. Among them, 38 % could perceive their tinnitus during lucid dreams, and this was strongly associated with the concomitant perception of external sounds during lucid dreaming. While the majority of patients report perceiving their tinnitus instantly upon awakening, during nocturnal awakenings, 17.2 % declared they could be awakened by their tinnitus and 10.0 % mentioned that their tinnitus can temporarily cease.</div></div><div><h3>Conclusions</h3><div>Our findings confirm the previous findings: tinnitus is rarely perceived during dreams. Remarkably, our study is the first to document the case of tinnitus during lucid dreaming. 64 % of these patients gain higher-order consciousness attributes while still experiencing a tinnitus-free state. Our observations suggest that the presence or absence of gating of external auditory information during dreams acts as a tinnitus on-off switch, refining the previously proposed integrative model of auditory phantom perception.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"458 ","pages":"Article 109204"},"PeriodicalIF":2.5,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143200367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Projections from the ventral nucleus of the trapezoid body to the dorsal cochlear nucleus in the rat: Morphology, distribution, and cellular origin","authors":"Mario Gómez-Martínez ,&nbsp;Héctor Rincón ,&nbsp;Marcelo Gómez-Álvarez ,&nbsp;Ricardo Gómez-Nieto ,&nbsp;Enrique Saldaña","doi":"10.1016/j.heares.2025.109200","DOIUrl":"10.1016/j.heares.2025.109200","url":null,"abstract":"<div><div>Animals integrate auditory and somatosensory stimuli because the perception of sounds depends not only on their position relative to the sound source, but also on the posture of the head and ears. In the mammalian brain, audiotactile integration already occurs in the dorsal cochlear nucleus (DCN), a very early station of the central auditory pathway. In the DCN, auditory inputs preferentially target the deep layer, whereas somatosensory inputs innervate granule cells, whose axons target the superficial, molecular layer. However, there is an often overlooked major pathway that presumably conveys direct auditory information to the molecular layer of the DCN: the projection from the contralateral ventral nucleus of the trapezoid body (VNTB), first characterized by Warr and Beck (1996, Hear. Res., 93:83–101).</div><div>To investigate in detail the morphology and distribution of the VNTB-to-DCN projection, we injected the bidirectional tracer biotinylated dextran amine (BDA) into the VNTB of adult rats and analyzed the axons that innervate the DCN. Moreover, to identify the neurons that innervate the DCN, we injected BDA into the DCN and analyzed the retrogradely labeled VNTB neurons.</div><div>Our results show that the VNTB-to-DCN projection is very predominantly contralateral. The axons reach the cochlear nuclei via the rostral part of the trapezoid body. Within the DCN, VNTB axons form a very dense plexus that covers the entire molecular layer and, to a lesser extent, the underlying fusiform cell layer. These axons bear a high number of <em>en passant</em> and terminal synaptic boutons. In the plexus, parasagittal bands of higher density perpendicular to the pial surface alternate with bands of lower density. The VNTB-to-DCN projection is tonotopic. The DCN is innervated by medium-sized multipolar neurons that occupy the ventral two-thirds of the VNTB and are distributed throughout the rostrocaudal extent of the nucleus. Moreover, the deep layer of the DCN is innervated by the ipsilateral lateral nucleus of the trapezoid body.</div><div>Although the biological role of the VNTB-to-DCN projection remains unknown, the available evidence from the literature suggests that it is GABAergic. Given its density, the projection may be very relevant to the functions of the DCN. Therefore, this projection should be considered in future investigations of DCN physiology and pathology, and should be incorporated into future morphofunctional schemes and models of the DCN.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"458 ","pages":"Article 109200"},"PeriodicalIF":2.5,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143349570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rational design of a Lfng-enhancer AAV construct drives specific and efficient gene expression in inner ear supporting cells","authors":"Richard Seist ,&nbsp;Juwan S. Copeland ,&nbsp;Litao Tao ,&nbsp;Andrew K. Groves","doi":"10.1016/j.heares.2025.109203","DOIUrl":"10.1016/j.heares.2025.109203","url":null,"abstract":"<div><div>Achieving cell-specific gene expression is crucial in the design of safe and efficacious gene therapies for the treatment of sensorineural hearing loss. Although a variety of adeno-associated virus (AAV) serotypes have been used to deliver genes to inner ear hair cells, few serotypes currently allow specific targeting of supporting cells. We sought to specifically target supporting cells by combining an AAV serotype with high tropism for the inner ear with enhancer sequences from the supporting cell-specific gene Lunatic Fringe (<em>Lfng</em>). We identified three candidate <em>Lfng</em> enhancer sequences using bioinformatic analysis to identify accessible chromatin and histone marks associated with active transcription of the <em>Lfng</em> locus in supporting cells. Candidate <em>Lfng</em> enhancers or the ubiquitous CBh promoter driving an EGFP reporter gene were packaged into the AAV-ie capsid, and the virus was introduced into the inner ear of neonatal mice. AAV-CBh-EGFP transduced multiple sensory and non-sensory inner ear cell types, as well as cells in the brain. One of the three <em>Lfng</em> enhancers gave robust EGFP expression in border cells, inner phalangeal cells, pillar cells, and all three rows of Deiters' cells along the entire cochlear duct, as well as in vestibular organ supporting cells. Significantly, no fluorescently labeled cells were detected in the brains of mice injected with this virus. We further designed an AAV-<em>Lfng</em>-CreERT2 vector that drove strong recombination in Cre reporter mice supporting cells after tamoxifen treatment. Our results provide a tool to specifically target supporting cells of the juvenile and adult inner ear.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"458 ","pages":"Article 109203"},"PeriodicalIF":2.5,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143074709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perilymph sampling in Mongolian gerbil, technical note and procedure evaluation.","authors":"Claire Olivier ,&nbsp;Cyril Beck ,&nbsp;Michaël Risoud ,&nbsp;Pierre Emmanuel Lemesre ,&nbsp;Juergen Siepmann ,&nbsp;Florence Siepmann ,&nbsp;Jeremy Vérin ,&nbsp;Jean-François Goossens ,&nbsp;Mostafa Kouach ,&nbsp;Antonino Bongiovanni ,&nbsp;Thomas Hubert ,&nbsp;Meryem Tardivel ,&nbsp;Christophe Vincent ,&nbsp;Philippine Toulemonde","doi":"10.1016/j.heares.2025.109188","DOIUrl":"10.1016/j.heares.2025.109188","url":null,"abstract":"<div><h3>Objective</h3><div>The aim of this study is to detail and evaluate the surgical procedure for perilymph sampling from the cochlear apex in the Mongolian gerbil.</div></div><div><h3>Design</h3><div>Perilymph sampling from the cochlear apex was performed one to three time in 12 male gerbils aged 8 to 12 months via the submandibular route. 11 of them were previously implanted with intracochlear implants loaded with dexamethasone and placed in the scala tympani, the 12th was used to collect control samples. The procedure was performed under general gas anesthesia, with head support, by a submandibular approach. After opening the bulla and sacrificing the external and middle ears, the cochlea was exposed and perilymph sampled. Macroscopic features of perilymph samples were reported before an HPLC-MS/MS assay to detect and quantify dexamethasone. Some cochleae were then harvested, immunostained and cleared to study fibrosis formation along the labyrinth and evaluate the consequences of multiple sampling procedures.</div></div><div><h3>Results</h3><div>The perilymph sampling procedure was technically difficult and required experimenter training. The procedure was well tolerated by the animals. One drawback of this technique in our gerbil model was the need to sacrifice the external ear, eardrum and ossicular chain to allow sufficient exposure for a quality procedure. Our technique enabled the collection of perilymph samples of the desired volume. Most of our samples were contaminated by bleeding from the otic capsule bone secondary to the cochleostomy. Nevertheless, HPLC-MS/MS analyses which successfully found dexamethasone in the perilymph of implanted gerbils, confirmed that our method was suitable for pharmacokinetic analyses. The occurrence of areas of fibrosis in the labyrinth after a sampling procedure compromises the quality and reliability of subsequent samples from the same animal.</div></div><div><h3>Conclusion</h3><div>The Mongolian gerbil is an animal model that can be used to collect perilymph from the cochlear apex to perform pharmacokinetic studies. The number of samples taken from a single animal must be limited to one.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"458 ","pages":"Article 109188"},"PeriodicalIF":2.5,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143058873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Musically evoked emotions in cochlear implant users and those with no known hearing loss","authors":"Samantha R. O'Connell,&nbsp;Julianne M. Papadopoulos,&nbsp;Daniel Inouye,&nbsp;Brandon J. van der Donk,&nbsp;Helena Gan,&nbsp;Raymond L. Goldsworthy","doi":"10.1016/j.heares.2025.109196","DOIUrl":"10.1016/j.heares.2025.109196","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Background&lt;/h3&gt;&lt;div&gt;Cochlear implants provide the profoundly deaf excellent speech comprehension; however, perception and appreciation of music remains a challenge. Previous work suggests that cochlear implant users, compared to normal-hearing listeners, have diminished perception of certain musically evoked emotions due to deficits in hearing pitch-related musical elements. The purpose of this study was to investigate how well cochlear implants users use pitch-based information to identify the emotional intent of music.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods&lt;/h3&gt;&lt;div&gt;Twenty-six cochlear implant users and 24 peers with no known hearing loss completed a set of online auditory measures. Participants were asked to rate the valence and arousal of 10 happy, 10 sad, 10 scary, and 10 peaceful melodies as categorized by Vieillard et al. (2008). Melodies that were previously categorized as peaceful and sad were then altered from major to minor modes (peaceful to peaceful-modified) and from minor to major (sad to sad-modified), respectively. Additionally, the tempo of these melodies was controlled at 60 beats per minute. Participants then valence and arousal of these 10 sad, 10 sad-modified, 10 peaceful, and 10 peaceful-modified melodies. Participants completed a series pitch perception tasks including major and minor melody and arpeggio discrimination and melodic contour identification. During data analysis, correlations between valence and arousal ratings, major and minor melody and arpeggio discrimination scores, and melodic contour identification scores were assessed.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;When listening to the unmodified melodies from Viellaird et al. (2008), both cochlear implant users and those with no known hearing loss rated happy melodies more distinctly in valence and arousal than sad, peaceful, and scary melodies. Cochlear implant users rated the valence of sad and peaceful melodies more similarly compared to those with no known hearing loss. When listening to the modified melodies, cochlear implant users rated original and modified sad and peaceful melodies similarly on the dimensions of valence and arousal. This contrasts with results found in those with no known hearing loss who utilized mode changes to rate melodies in major modes higher in valence than melodies in minor modes. For major and minor melody and arpeggio discrimination, those with no known hearing loss performed close to or at ceiling while cochlear implant users mostly performed in the chance range. Finally, for melodic contour identification, many cochlear implant users performed significantly worse than those with no known hearing loss.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Conclusion&lt;/h3&gt;&lt;div&gt;This study further reveals the challenges that cochlear implant patients face in using modal cues to perceive the emotional intent of music. While cochlear implant users are able to utilize tempo cues to derive the emotional intent of melodies to an extent, they struggle once these cues are","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"458 ","pages":"Article 109196"},"PeriodicalIF":2.5,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143200366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct cell classes in the superior paraolivary nucleus (SPN) region in the gerbil auditory brainstem revealed by in vivo physiological and anatomical characterization","authors":"T.P. Franken ,&nbsp;P.X. Joris ,&nbsp;P.H. Smith","doi":"10.1016/j.heares.2025.109202","DOIUrl":"10.1016/j.heares.2025.109202","url":null,"abstract":"<div><div>The superior para-olivary nucleus (SPN or SPON) is a prominent nucleus in the superior olivary complex of the auditory brainstem. The cellular composition of the nucleus reportedly differs between species, but a prominent recurring feature is the unusual characteristic to not respond during a sound but at its offset. Blocking glycine has shown that sound-induced inhibition is the mechanism, but the time course of the responsible synaptic events has not been directly measured <em>in vivo</em>. We obtained intracellular recordings in the Mongolian gerbil (<em>meriones unguiculatus</em>) with patch electrodes containing biocytin, and retrieved 12 labeled neurons with large dendritic trees within and around the SPN region. We found that these neurons could be categorized into three classes that show consistency along multiple dimensions like ultrastructure, spontaneous activity, and responses to current injection and a variety of ipsi- and contralateral sounds. Fast cells fire at onset of depolarizing current, generate short-latency rebound spikes to sound or hyperpolarizing current, and show dense synaptic coverage. Slow cells show sparse synaptic coverage, sustained responses to depolarization, and inhibition with a slow time course to hyperpolarizing current or sound. Uninhibited cells form a third class which profoundly differ in their responses to sound, lacking rebound spiking. We propose that fast cells project to the inferior colliculus, and slow cells to the cochlear nucleus.</div></div>","PeriodicalId":12881,"journal":{"name":"Hearing Research","volume":"458 ","pages":"Article 109202"},"PeriodicalIF":2.5,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143200369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}