Search Results (127)

Background: Inner hair cell (IHC) ribbon synapses are the initial synapses in the auditory pathway, comprising presynaptic ribbons and postsynaptic glutamate receptors on the peripheral afferent fibers. The excitatory neurotransmitter glutamate primarily signals through AMPA-type heterotetrameric receptors (AMPARs), composed of GluR1, GluR2, GluR3, and GluR4 subunits. Research shows that corticosterone affects AMPA receptor subunits in the central nervous system. The present study investigates the effects of corticosterone on AMPA receptor subunits in the murine cochlea. Methods: Cochlear explants were isolated from male and female C57BL/6 pups (postnatal days 4–5), treated for 20 min with 100 nM corticosterone, and cultured for an additional 24 h. The concentration of AMPAR protein subunits was quantified using an ELISA assay, while gene expression was analyzed using RT-PCR. The synaptic localization patterns of GluR2 and Ribeye were examined using immunofluorescence and confocal microscopy. Results: Male C57BL/6 mice have a significantly greater basal concentration of the GluR2 subunit than females and more GluR2 puncta per IHC than females. Corticosterone increases the size of Ribeye in males and increases twofold GluR2/Ribeye colocalization in the apical region of females. Conclusions: Exposure of membranous cochleae to corticosterone induces changes consistent with neuroplasticity in the auditory periphery. The observed effect is sex-dependent. Full article

Background and Objectives: Currently, there are no proven solutions to remediate cognitive deficits in people with a mild traumatic brain injury (mTBI). One common issue is visual timing deficits, which may be due to processing deficits in dorsal visual pathways. Methods: This study investigates whether a new intervention (PATH) aimed at improving these visual timing deficits is more effective than conventional cognitive therapies that either remediate: (1) pattern discrimination deficits (ventral visual pathway): Orientation Discrimination (OD), or (2) working memory deficits using ReCollect task, for 10 subjects between the ages of 26–60 years old. This study tests the ability of three different cognitive therapies to improve the primary outcome: visual working memory (VWM), and secondary outcomes: processing speed, auditory working memory, and selective attention in mTBI subjects based on neuropsychological tests administered before and after 36 30-min training sessions Monday, Wednesday and Friday mornings. Results: On average, the PATH group exhibited a 35% improvement in VWM, compared to 15% for ReCollect and 5% for OD. A repeated-measures ANOVA found that improving dorsal stream function improved VWM significantly more than found after the other two interventions. The results reveal the importance of strengthening dorsal pathways more than conventional cognitive therapies to improve cognitive skills after mTBI. A biomarker, MagnetoEncephaloGraphy (MEG) brain recordings, using an N-Back task for subjects in treatment groups, verified these improvements as well. Conclusions: The data from this preliminary study are very promising for a new method improving the brain’s timing, more effective than conventional therapies, to improve cognitive deficits in mTBI patients. Full article

The widespread adoption of background music in workplaces contrasts with the inconsistent empirical evidence regarding its cognitive effects, particularly concerning how music types influence the sequential pathway from flow states to work engagement and task performance. While prior research identifies flow and engagement as potential mediators, theoretical conflicts persist regarding their temporal dynamics and susceptibility to auditory habituation. This study tested three hypotheses: (1) music type indirectly affects performance through flow–engagement mediation, (2) high-arousal music impairs while structured compositions (e.g., Mozart’s K448) enhance this pathway, and (3) repeated exposure diminishes music’s efficacy. A two-phase longitudinal experiment with 428 Chinese undergraduates employed structural equation modeling (SEM) to analyze data from randomized groups (control, high-arousal, low-arousal, and Mozart K448), completing Backward Digit Span tasks under controlled auditory conditions. The results confirmed Mozart K448’s superior immediate mediation effect (β = 0.118, 95% CI [0.072, 0.181]) compared to high-arousal music’s detrimental impact (β = −0.112, 95% CI [−0.182, −0.056]), with flow fully mediating engagement’s influence on performance. A longitudinal analysis revealed a 53% attenuation in Mozart’s flow-enhancing effect after a 30-day familiarization (B = 0.150 vs. baseline 0.321), though residual benefits persisted. These findings reconcile the cognitive tuning and arousal–mood hypotheses by proposing a hybrid model where music initially operates through a novelty-driven dopamine release before transitioning to schema-based cognitive priming. Practically, the results advocate tiered auditory strategies: deploying structured music during skill acquisition phases while rotating selections to counter habituation. The study highlights the cultural specificity in auditory processing, challenging universal prescriptions and underscoring the need for localized music policies. By integrating flow theory with neurocognitive habituation models, this research advances evidence-based guidelines for optimizing workplace auditory environments. Full article

Background/Objectives: A sizeable population of patients with normal pure-tone audiograms endorse a consistent difficulty of following conversations in noisy environments. Termed hidden hearing loss (HHL), this condition evades traditional diagnostic methods for hearing loss and thus is significantly under-diagnosed and untreated. This review sought to identify emerging methods of diagnosing HHL via measurement of its histopathologic correlate: cochlear synaptopathy, the loss of synapses in the auditory nerve pathway. Methods: A thorough literature search of multiple databases was conducted to identify studies with objective, electrophysiological measures of synaptopathy. The PRISMA protocol was employed to establish criteria for the selection of relevant literature. Results: A total of 21 studies were selected with diagnostic methods, including the auditory brainstem response (ABR), electrocochleography (EcochG), middle ear muscle reflex (MEMR), and frequency-following response (FFR). Measures that may indicate the presence of synaptopathy include a reduced wave I amplitude of ABR, reduced SP amplitude of EcochG, and abnormal MEMR, among other measurements. Behavioral measures were often performed alongside electrophysiological measures, the most common of which was the speech-in-noise assessment. Conclusions: ABR was the most common diagnostic method for assessing HHL. Though ABR, EcochG, and MEMR may be sensitive to measuring synaptopathy, more literature comparing these methods is necessary. A two-pronged approach combining behavioral and electrophysiological measures may prove useful as a criterion for diagnosing and estimating the extent of pathology in affected patients. Full article

Epilepsy is a multifaceted neurological disorder characterized by recurrent seizures and associated with molecular and immune alterations in key brain regions. The GASH/Sal (Genetic Audiogenic Seizure Hamster, Salamanca), a genetic model for audiogenic epilepsy, provides a powerful tool to study seizure mechanisms and resistance in predisposed individuals. This study investigates the proteomic and immune responses triggered by audiogenic kindling in the inferior colliculus, comparing non-responder animals exhibiting reduced seizure severity following repeated stimulation versus GASH/Sal naïve hamsters. To assess auditory pathway functionality, Auditory Brainstem Responses (ABRs) were recorded, revealing reduced neuronal activity in the auditory nerve of non-responders, while central auditory processing remained unaffected. Cytokine profiling demonstrated increased levels of proinflammatory markers, including IL-1 alpha (Interleukin-1 alpha), IL-10 (Interleukin-10), and TGF-beta (Transforming Growth Factor beta), alongside decreased IGF-1 (Insulin-like Growth Factor 1) levels, highlighting systemic inflammation and its interplay with neuroprotection. Building on these findings, a proteomic analysis identified 159 differentially expressed proteins (DEPs). Additionally, bioinformatic approaches, including Gene Set Enrichment Analysis (GSEA) and Weighted Gene Co-expression Network Analysis (WGCNA), revealed disrupted pathways related to metabolic and inflammatory epileptic processes and a module potentially linked to a rise in the threshold of seizures, respectively. Differentially expressed genes, identified through bioinformatic and statistical analyses, were validated by RT-qPCR. This confirmed the upregulation of six genes (Gpc1—Glypican-1; Sdc3—Syndecan-3; Vgf—Nerve Growth Factor Inducible; Cpne5—Copine 5; Agap2—Arf-GAP with GTPase domain, ANK repeat, and PH domain-containing protein 2; and Dpp8—Dipeptidyl Peptidase 8) and the downregulation of two (Ralb—RAS-like proto-oncogene B—and S100b—S100 calcium-binding protein B), aligning with reduced seizure severity. This study may uncover key proteomic and immune mechanisms underlying seizure susceptibility, providing possible novel therapeutic targets for refractory epilepsy. Full article

As a distinct musical form, blues music from the Mississippi Delta has been extensively studied across various academic disciplines. While much of this attention has treated blues primarily as an auditory experience, I argue that it represents far more than just sound or entertainment. This research project examines Delta blues as a comprehensive cultural phenomenon, exploring its evolution through a series of distinct diffusionary pathways that reveal complex global interactions and transcultural exchange. This study posits that Delta blues emerged from a broad cultural milieu, shaped by multiple layers of geographical processes ranging from ancient African trade routes to twentieth-century migration patterns. I position Delta blues within the context of the African diaspora, emphasizing not only its strong roots in African and African American cultural traditions but also its crucial role as a vehicle for cultural resistance and consciousness-raising. By mapping the evolution of blues music and culture through specific circuits of exchange, I illuminate the intricate interrelationships between different peoples and places across time and space. This approach reveals how global interactions generated a unique musical and cultural expression that both embodies and transcends the complex social dynamics inherent in the African diaspora. Full article

Background: The brainstem auditory-evoked response (BAER) is an established electrophysiological measure of neural activity from the auditory nerve up to the brain stem. The BAER is used to diagnose abnormalities in auditory pathways and in neurophysiological human and animal research. However, normative data for BAERs in sheep, which represent an adequate large animal model for translational and basic otological research, are lacking. Objective: The aim of this study was to assess the function of the ovine auditory nervous system by determining normative values for the BAER and to compare sheep with human BAER data. Methods: In this retrospective study, BAER data for click stimuli at a range of sound pressure levels (SPLs) were analyzed. A series of 15 samples from six sheep with a mean age of 41.8 months was included. Results: The mean BAER threshold was 45.3 dB SPL. At 100 dB SPL, the mean (±standard deviation, SD) latency of wave V was 4.35 (±0.18) ms, that of wave III was 2.44 (±0.15) ms, and that of wave I was 0.88 (±0.13) ms. At 100 dB SPL, the mean interpeak latency of waves I–III was 1.56 (±0.18) ms, that of waves III–V was 1.91 (±0.16) ms, and that of waves I–V was 3.47 (±0.20) ms. The mean amplitudes at 100 dB SPL were 0.04 (±0.03) µV for wave I, 0.50 (±0.24) µV for wave III, and 0.40 (±0.25) µV for wave V. Conclusions: The normative values for sheep BAERs were reproducible and similar to those of humans. The normative BAER values further support sheep as an adequate animal model for otological research. Full article

Canine functional magnetic resonance imaging (fMRI) neurocognitive studies represent an emerging field that is advancing more gradually compared to progress in human fMRI research. Given the potential benefits of canine fMRI for veterinary, comparative, and translational research, this systematic review highlights significant findings, focusing on specific brain areas activated during task-related and resting state conditions in dogs. The review addresses the following question: “What brain areas in dogs are activated in response to various stimuli?”. Following PRISMA 2020 guidelines, a comprehensive search of PUBMED, Scopus, and Web of Knowledge databases identified 1833 studies, of which 46 met the inclusion criteria. The studies were categorized into themes concerning resting state networks and visual, auditory, olfactory, somatosensory, and multi-stimulations studies. In dogs, resting state networks and stimulus-specific functional patterns were confirmed as vital for brain function. These findings reveal both similarities and differences in the neurological mechanisms underlying canine and human cognition, enhance the understanding of neural activation pathways in dogs, expand the knowledge of social bonding patterns, and highlight the potential use of fMRI in predicting the suitability of dogs for assistance roles. Further studies are needed to further map human–canine similarities and identify the unique features of canine brain function. Additionally, implementing innovative human methods, such as combined fMRI–magnetic resonance spectroscopy (MRS), into canine neurocognitive research could significantly advance the field. Full article

Background/Objectives: Before a cochlear implant is considered, patients undergo various audiological tests to assess their suitability. One key test measures the auditory brainstem response (ABR) to acoustic stimuli. However, in some cases, even with maximum sound stimulation, no response is detected. Methods: The promontory test involves electrical stimulation near the auditory nerve, allowing patients to associate the sensation. Ideally, the electrode is placed in the middle ear after opening the eardrum. This method, along with trans-tympanic electrically evoked ABR in local anesthesia (LA-TT-EABR) and the cortical equivalent (LA-TT-EALR), helps assess the auditory nerve’s existence and excitability. The TympEALR test, utilizing a “tympanic LA-TT-EALR”, provides an alternative measurement. Previous research has shown the possibility of deriving brainstem and cortical potentials through trans-tympanic electrical stimulation, allowing for objective assessment of the auditory nerve’s integrity and potentially objectifying patient sensations. Results: Sixteen patients have been tested using TympEALR. In seven of these, we found a positive response. The morphology was similar to other electrically evoked cortical auditory responses (EALR), e.g., using cochlear implants or trans-tympanic stimulation electrodes. We observed a higher influence of electrical artifacts than in other EALRs. Conclusions: TympEALR showed positive results in nearly half of the study participants, potentially avoiding invasive procedures. TympEALR can be a valuable alternative to trans-tympanic methods. More research is needed to determine if a negative result suggests against cochlear implantation. Full article

Emotional communication is a multi-modal phenomenon involving posture, gestures, facial expressions, and the human voice. Affective states systematically modulate the acoustic signals produced during speech production through the laryngeal muscles via the central nervous system, transforming the acoustic signal into a means of affective transmission. Additionally, a substantial body of research in sonobiology has shown that audible acoustic waves (AAW) can affect cellular dynamics. This pilot study explores whether the physical–acoustic changes induced by gratitude states in human speech could influence cell proliferation and Ki67 expression in non-auditory cells (661W cell line). We conduct a series of assays, including affective electroencephalogram (EEG) measurements, an affective text quantification algorithm, and a passive vibro-acoustic treatment (PVT), to control the CO₂ incubator environment acoustically, and a proliferation assay with immunolabeling to quantify cell dynamics. Although a larger sample size is needed, the hypothesis that emotions can act as biophysical agents remains a plausible possibility, and feasible physical and biological pathways are discussed. In summary, studying the impact of gratitude AAW on cell biology represents an unexplored research area with the potential to enhance our understanding of the interaction between human cognition and biology through physics principles. Full article

Integrating multi-modal data in natural language processing has opened new pathways for the enhancement of dialogue summarization. However, existing models often struggle to effectively synthesize textual, auditory, and visual inputs. This paper introduces a Modality-Enhanced Multi-Channel Attention Network (MEMA), a novel approach designed to optimize the integration and interaction of diverse modalities for dialogue summarization. MEMA leverages symmetrical embedding strategies to balance the integrity and distinctiveness of each modality, ensuring a harmonious interaction within the unified architecture. By maintaining symmetry in the processing flow, MEMA enhances the contextual richness and coherence of the generated summaries. Our model demonstrates superior performance on the Multi-modal Dialogue Summarization (MDS) dataset, particularly in generating contextually enriched abstract summaries. The results underscore MEMA’s potential to transform dialogue summarization by providing a more symmetrical and integrated understanding of multi-modal interactions, bridging the gap in multi-modal data processing, and setting a new standard for future summarization tasks. Full article

Presbycusis, also referred to as age-related hearing loss (ARHL), is a multifaceted condition caused by the natural aging process affecting the auditory system. Genome-wide association studies (GWAS) in human populations can identify potential genes linked to ARHL. Despite this, our knowledge of the biochemical and molecular mechanisms behind the condition remains incomplete. This study aims to evaluate a potential protective tool for ARHL treatment by comparing human blood-based target gene-miRNA associations regulated in ARHL. To identify promising target genes for ARHL, we utilized an mRNA assay. To determine the role of miRNA in ARHL, we investigated the expression profile of miRNA in whole blood in ARHL patients with real-time polymerase chain reaction (RT-qPCR). A reporter gene assay was performed to confirm the regulation of candidate genes by microRNA. Through RT-qPCR validation analysis, we finally confirmed the relationship between ARHL and the role of the interferon-gamma (IFNG) gene. This gene can be regarded as an age-related gene. Through gene ontology (GO) analysis, it has been found that these genes are enriched in pathways related to apoptosis. Among them, IFNG induces an inflammatory response, apoptotic cell death, and cellular senescence. We found that miR-409-3p downregulates the expression of the IFNG in vitro. In addition, the downregulation of the IFNG by miRNA 409-3p promoted cell apoptosis and suppressed proliferation. In conclusion, our study produced gene signatures and associated microRNA regulation that could be a protective key for ARHL patients. IFNG genes and miR-409-3p should be investigated for their usefulness as a new biomarker for treatment modality. Full article

As cities progress into high-quality developments, the demand for urban parks that enhance residents’ well-being and sustainability is increasing. Traditional visual-centric design methods no longer suffice. Given that vision and hearing are the primary sensory pathways through which people perceive their environment, exploring their relationship with landscape experiences offers a novel perspective for optimizing the audiovisual perception quality of urban parks. This study explores the relationship between visual and auditory elements and landscape experiences to optimize urban parks’ sensory quality. Using visual perception, soundscape perception, sound source perception, and behavioral vitality, this study evaluates the audiovisual perception quality of a representative wetland park in Chengdu’s ring ecological zone. By quantifying relationships between audiovisual characteristics, behavioral vitality, and emotional feedback, several emotional assessment models were constructed. The results show that lawns, pavements, and sound pressure levels significantly impact vitality. A sound pressure level of 77 dB has been identified as a critical threshold in emotional perception models. Consequently, distinct emotional prediction models can be employed to enhance landscape design across various sound pressure level zones. This research provides scientific evidence and flexible strategies for designing urban open spaces that improve landscape experiences based on multisensory perception. Full article

The integrity of the blood–labyrinth barrier (BLB) is essential for inner ear homeostasis, regulating the ionic composition of endolymph and perilymph and preventing harmful substance entry. Endothelial hyperpermeability, central in inflammatory and immune responses, is managed through complex intercellular communication and molecular signaling pathways. Recent studies link BLB permeability dysregulation to auditory pathologies like acoustic trauma, autoimmune inner ear diseases, and presbycusis. Polymorphonuclear granulocytes (PMNs), or neutrophils, significantly modulate vascular permeability, impacting endothelial barrier properties. Neutrophil extracellular traps (NETs) are involved in diseases with autoimmune and autoinflammatory bases. The present study evaluated the impact of NETs on a BLB cellular model using a Transwell^® setup. Our findings revealed a concentration-dependent impact of NETs on human inner ear-derived endothelial cells. In particular, endothelial permeability markers increased, as indicated by reduced transepithelial electrical resistance, enhanced dextran permeability, and downregulated junctional gene expression (ZO1, OCL, and CDH5). Changes in cytoskeletal architecture were also observed. These preliminary results pave the way for further research into the potential involvement of NETs in BLB impairment and implications for auditory disorders. Full article

Aging, a complex process marked by molecular and cellular changes, inevitably influences tissue and organ homeostasis and leads to an increased onset or progression of many chronic diseases and conditions, one of which is age-related hearing loss (ARHL). ARHL, known as presbycusis, is characterized by the gradual and irreversible decline in auditory sensitivity, accompanied by the loss of auditory sensory cells and neurons, and the decline in auditory processing abilities associated with aging. The extended human lifespan achieved by modern medicine simultaneously exposes a rising prevalence of age-related conditions, with ARHL being one of the most significant. While our understanding of the molecular basis for aging has increased over the past three decades, a further understanding of the interrelationship between the key pathways controlling the aging process and the development of ARHL is needed to identify novel targets for the treatment of AHRL. The dysregulation of molecular pathways (AMPK, mTOR, insulin/IGF-1, and sirtuins) and cellular pathways (senescence, autophagy, and oxidative stress) have been shown to contribute to ARHL. However, the mechanistic basis for these pathways in the initiation and progression of ARHL needs to be clarified. Therefore, understanding how longevity pathways are associated with ARHL will directly influence the development of therapeutic strategies to treat or prevent ARHL. This review explores our current understanding of the molecular and cellular mechanisms of aging and hearing loss and their potential to provide new approaches for early diagnosis, prevention, and treatment of ARHL. Full article