Search Results (115)

Background: Gamma-range auditory steady-state responses (ASSRs) are emerging as promising translational biomarkers of neural network function. While extensively studied in human neuropsychiatric and neurodevelopmental research, their application in animal models has expanded in recent years, providing mechanistic insights into disease-related neural dynamics. However, methodological approaches vary widely, findings remain fragmented, and outcomes are not easily generalized. Methods: A literature search was conducted in March 2025 across PubMed and Scopus to identify studies investigating gamma-range ASSRs (30–100 Hz) in animal models with relevance to psychiatric and developmental conditions. Results: Most studies employed rodents, with a smaller number involving non-human primates, and used pharmacological, genetic, lesion-based, or developmental manipulations relevant to schizophrenia, autism spectrum disorder, and related conditions. ASSRs were highly sensitive to NMDA receptor antagonism, state- and trait-related factors, and exhibited region- and layer-specific generation patterns centered on the auditory cortex. Less common paradigms, such as chirps and gap-in-noise, also demonstrated translational potential. Conclusions: Animal research confirms that gamma-range ASSRs provide a sensitive, cross-species readout of circuit dysfunctions observed in psychiatric and neurodevelopmental disorders. To maximize their translational utility, future work should prioritize methodological harmonization, systematic inclusion of sex and behavioral state factors, and replication across laboratories. Strengthening these aspects will enhance the value of ASSRs as biomarkers for early detection, patient stratification, and treatment monitoring in clinical psychiatry. Full article

Hearing loss and serotonergic dysfunction both impact social and cognitive behaviors, yet their neurobiological interplay remains poorly understood. This study investigated whether perinatal fluoxetine exposure alters myelination in (auditory) brain regions during development. Female Wistar rats received 10 mg/kg fluoxetine from gestational day 1 until postnatal day (PND)21. Brain tissue was collected from male offspring at PND21 and PND35. Myelination was assessed via immunohistochemical analysis of Myelin-Associated Glycoprotein (MAG) and Myelin Basic Protein (MBP) in the auditory cortex, inferior colliculus, and corpus callosum. MAG+ cell counts, MBP+ area, and MBP fluorescence intensity were quantified. No major effects of fluoxetine were observed on myelin markers in any brain region or developmental stage. However, changes in myelination emerged between PND21 and PND35. MAG+ cell density declined in the inferior colliculus but remained stable in the auditory cortex. MBP+ area decreased over time in both the corpus callosum and auditory cortex, while MBP fluorescence intensity increased in the corpus callosum. These results suggest that myelination changes between PND21 and PND35 are region- and age-dependent and not altered by fluoxetine. These findings highlight the dynamic nature of postnatal myelination and suggest that serotonergic alterations alone may be insufficient to disrupt structural maturation in auditory regions. Full article

Background: Recreational noise exposure from personal listening devices (PLDs) may lead to hidden hearing loss (HHL), affecting auditory nerve function despite normal pure-tone audiometry (PTA) and otoacoustic emissions (OAE). Subclinical auditory damage at the synaptic level often goes undetected by conventional assessments, emphasizing the need for more sensitive measures. Recorded click ABR in the presence of various levels of ipsilateral maskers for the better identification of auditory damage at the synaptic level. These results could help to develop a better objective diagnostic tool that can detect hidden hearing loss. Objective: To examine the effects of PLD usage on extended high-frequency audiometric thresholds and on click-evoked auditory brainstem responses (ABR) with and without ipsilateral masking in individuals with normal hearing. Materials and Methods: Thirty-five young adults aged 18–35 years (18 PLD users, 17 controls) with clinically normal hearing were recruited. Extended high-frequency audiometry (EHFA) was conducted from 9 to 16 kHz. Click-evoked ABRs were recorded at 80 dB nHL under unmasked and ipsilateral broadband noise-masked conditions at 50, 60, and 70 dB SPL. ABR analyses included absolute and relative amplitude (V/I) and latencies of waves I, III, and V. Results: PLD users demonstrated significantly elevated extended high-frequency thresholds compared to controls. ABR analyses revealed reduced Wave I amplitudes across stimulus conditions in PLD users, while Wave V amplitudes were largely preserved, resulting in consistently higher V/I amplitude ratios under masked conditions. No group differences were observed for Wave III amplitudes or absolute/interpeak latencies, except for a modest prolongation of I–III latency at one masker level in PLD users. Conclusions: Conventional audiological tests may not detect early auditory damage; however, extended high-frequency audiometry and ABR with ipsilateral masking demonstrate greater sensitivity in identifying noise-induced functional changes within the auditory brainstem pathways. Full article

Background/Objectives: Dysregulated gamma oscillations are associated with cognitive dysfunction. Auditory stimulation at 40 Hz enhances neural activity in brain regions associated with learning, attention, and memory. This study assessed the safety and acceptability of 40 Hz amplitude-modulated auditory stimulation in healthy older people. Auditory stimuli were created using popular songs, where vocals and background music were separated and independently amplitude-modulated at 40 Hz with different modulation depths to generate periodic 40 Hz gamma waveforms. Methods: In this open-label, single-arm study, healthy participants aged ≥65 years received 40 Hz amplitude-modulated auditory stimulation daily via a smartphone for 28 days through earphones/headphones. Safety was assessed through adverse event (AE) monitoring and changes in clinical scores for depression, cognitive function, and hearing thresholds. Acceptability was evaluated by adherence rates, listening time, dropout reasons, volume levels, intent for future use, and subjective impressions of the sound source on a 7-point Likert scale. Results: Among 28 participants (mean age 69.1 years, 53.6% female), six reported 12 AEs, with six considered device-related (e.g., ear discomfort, jaw pain, musculoskeletal stiffness). The AEs observed were mild or moderate. Scores for cognitive function, depression, and hearing thresholds did not worsen during the study period. Adherence was observed in 96.4%, with 85.7% expressing interest in continuing. Most participants rated the sounds’ unnaturalness between 2 and 3 and discomfort between 1 and 3 on the 7-point Likert scale. Conclusions: The intervention was well tolerated and acceptable in study participants, with no major safety concerns identified. Auditory stimulation did not cause severe discomfort or reduce acceptability. Further studies should explore the long-term effects and broader clinical applications. Full article

Hyper-IgE syndrome (HIES) is a rare genetic immunodeficiency characterized by elevated serum IgE levels and associated immune dysregulation, manifesting in recurrent infections, eczema, and skeletal abnormalities. Emerging evidence suggests a link between HIES and audiovestibular dysfunction, potentially mediated by IgE-driven inflammation in the inner ear, which is not immunologically privileged. However, the nature of this association remains poorly understood. This systematic review synthesizes current evidence on the characteristics, pathophysiology, diagnostic approaches, and management of audiovestibular dysfunction in HIES patients. Literature searches across PubMed, Embase, ClinicalKey, Web of Science, and ScienceDirect (up to 6 August 2025) were conducted in accordance with PRISMA guidelines. Key findings indicate that HIES-related audiovestibular issues, including sensorineural hearing loss and vestibular impairment, may arise from IgE-mediated endolymphatic sac inflammation, leading to hydrops and hair cell damage. Diagnostic tools such as audiometry, electrocochleography, and allergen challenge tests show promise, with elevated IgE correlating with abnormal otoacoustic emissions and prolonged auditory brainstem response latencies. Treatment focuses on immunomodulation (e.g., corticosteroids, dupilumab) to mitigate IgE effects, though evidence is limited to case reports. A proposed schematic diagram illustrates pathophysiology, emphasizing IgE’s role in inner ear toxicity. Timely recognition and intervention may prevent progression to permanent hearing loss or vestibular disability, improving quality of life. Future research should explore genetic–immunologic mechanisms and prospective trials for targeted therapies. Trial registration: PROSPERO CRD420251120600. Full article

Background and Objectives: Sensorineural hearing loss (SNHL) is influenced by various causes, including thyroid diseases. For example, hypothyroidism and thyroid autoimmunity can damage the inner ear through hormonal, immune, and vascular mechanisms. Vestibular disorders like Ménière’s disease (MD) and benign paroxysmal positional vertigo (BPPV) also show possible associations with thyroid dysfunction. Materials and Methods: A review following PRISMA guidelines searched PubMed, Scopus, and Google Scholar for studies linking thyroid disorders with inner ear dysfunction. Results: Out of 985 screened records, 30 studies met inclusion criteria, involving various thyroid disorders, primarily hypothyroidism and autoimmune thyroiditis. Scientific evidence supports a correlation between hypothyroidism and hearing impairment. However, some studies also suggest a link between hyperthyroidism and inner ear disorders, particularly focusing on the role of autoimmunity in this context. Concerning vestibular dysfunction, the available studies are less abundant and support a significant association between thyroid disease and Meniere’s disease. Conclusions: There is a clear correlation between hypothyroidism and auditory function. A substantial body of literature also supports an association with vestibular disorders, although some discrepancies remain. Further research is needed to elucidate the underlying pathophysiological mechanisms (e.g., autoimmune, vascular, metabolic) involved with this correlation. Full article

Objectives: We examined whether sensory inhibition was altered in patients with autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) as deficits in the neural inhibition are considered to be involved in both disorders. Methods: By using auditory change-related brain potentials as the test response, paired pulse suppression (PPS) and prepulse inhibition (PPI) were compared among healthy controls (n = 57), patients with ASD (n = 22), and ADHD (n = 8). The test change-related response was elicited by an abrupt sound pressure increase in a continuous sound. In the PPS experiment, two 15 dB change stimuli were given 600 ms apart to elicit two change-related responses. In the PPI experiment, the test stimulus of a 10 dB increase and prepulse of a 2 dB increase were given with an interval of 50 ms. Evoked potentials were recorded from Cz referenced to the linked mastoids. Results: PPS differed significantly among the three groups, with a significantly lower value for ADHD than controls. PPI was significantly lower for ASD and ADHD than normal controls. Conclusions: Since these two measures are thought to represent changes in circuit excitability due to preceding stimuli via GABAergic transmission, the present results support the idea that dysfunction of the GABAergic system contributes to the etiology of these disorders. The present results showed that the pattern of dysfunction differed between the two disorders and suggest that measurements of inhibitory function may be able to differentiate between the two disorders. Full article

Background: Hearing loss results from diverse biological insults along the auditory pathway, including sensory hair cell death, neural degeneration, and central auditory processing deficits. Implantable auditory neuroprostheses, such as cochlear and brainstem implants, aim to restore hearing by directly stimulating neural structures. Advances in neurobiology and device technology underpin the development of more sophisticated implants tailored to the biological complexity of auditory dysfunction. Aim: This narrative review of reviews aims to map the integration of artificial intelligence (AI) in auditory neuroprosthetics, analyzing recent research trends, key thematic areas, and the opportunities and challenges of AI-enhanced devices. By synthesizing biological and computational perspectives, it seeks to guide future interdisciplinary efforts toward more adaptive and biologically informed hearing restoration solutions. Methods: This narrative review analyzed recent literature reviews from PubMed and Scopus (last 5 years), focusing on AI integration with auditory neuroprosthetics and related biological processes. Emphasis was placed on studies linking AI innovations to neural plasticity and device–nerve interactions, excluding purely computational works. The ANDJ (a standard narrative review checklist) checklist guided a transparent, rigorous narrative approach suited to this interdisciplinary, rapidly evolving field. Results and discussion: Eighteen recent review articles were analyzed, highlighting significant advancements in the integration of artificial intelligence with auditory neuroprosthetics, particularly cochlear implants. Established areas include predictive modeling, biologically inspired signal processing, and AI-assisted surgical planning, while emerging fields such as multisensory augmentation and remote care remain underexplored. Key limitations involve fragmented biological datasets, lack of standardized biomarkers, and regulatory challenges related to algorithm transparency and clinical application. This review emphasizes the urgent need for AI frameworks that deeply integrate biological and clinical insights, expanding focus beyond cochlear implants to other neuroprosthetic devices. To complement this overview, a targeted analysis of recent cutting-edge studies was also conducted, starting from the emerging gaps to capture the latest technological and biological innovations shaping the field. These findings guide future research toward more biologically meaningful, ethical, and clinically impactful solutions. Conclusions: This narrative review highlights progress in integrating AI with auditory neuroprosthetics, emphasizing the importance of biological foundations and interdisciplinary approaches. It also recognizes ongoing challenges such as data limitations and the need for clear ethical frameworks. Collaboration across fields is vital to foster innovation and improve patient care. Full article

Idiopathic normal-pressure hydrocephalus (iNPH) is clinically characterized by the Hakim–Adams triad: gait disturbance, cognitive decline, and urinary incontinence. Cognitive impairment in iNPH predominates as a subcortical syndrome, with deficits in executive functions, psychomotor slowing, and memory inefficiency. However, the cognitive profile is heterogeneous and often overlaps with other neurodegenerative conditions, complicating differential diagnosis. This study investigated the cognitive features of iNPH using the Rey Auditory Verbal Learning Test (RAVLT), comparing 29 iNPH patients to 28 healthy controls. Demographic and neuroimaging parameters—such as Evans Index and Callosal Angle—were assessed. Results indicated significantly lower Montreal Cognitive Assessment (MoCA) and RAVLT scores in iNPH patients compared to controls. Analysis of serial position effects revealed that, whereas healthy individuals exhibited typical primacy and recency effects in verbal memory, iNPH patients demonstrated a selective impairment of the primacy effect, likely reflecting hippocampal dysfunction. These findings underline the importance of detailed neuropsychological evaluation in differentiating iNPH from other dementias and suggest that damage to medial temporal lobe structures plays a prominent role in the verbal memory deficit observed in iNPH. Full article

Background/Objectives: Temperament is an innate personality trait, influenced by genetic, biological, and environmental factors. Hearing loss, particularly during the critical period of auditory development, can influence cognitive and temperamental development. This study aims to assess the impact of hearing loss on temperamental development in infants aged between 1 and 12 months. Methods: A cross-sectional study of a sample of 132 pediatric patients from the infant hearing screening program was conducted from June 2023 to June 2024. The infants were divided into two groups based on hearing status and the presence of risk factors; cognitive and temperamental parameters were assessed using the QUIT questionnaire. Results: No significant differences were found between infants with and without hearing loss when also considering the infants without risk factors. Normal temperament was found in infants with and without hearing loss, considering both risk and non-risk factors. Finally, no relationship between hearing loss degree and temperament type, considering both the absence and presence of risk factors, was observed. Conclusions: In the early months of an infant’s life, hearing loss does not appear to significantly affect temperamental development. Only through the monitoring of these hearing-impaired infants to detect more severe hearing loss and/or in the presence of other risk factors can deviant development be hypothesized. In this regard, multidisciplinary evaluations may be crucial for the early detection and correction of dysfunctional behaviors. Full article

Background/Objectives: This research focuses on the increasing presence of older workers in the labor market, a group particularly vulnerable to hearing problems due to age-related changes and prolonged noise exposure. Methods: The research combines theoretical and empirical approaches to investigate the impact of noise on the workplaces of older employees. The empirical component is based on two primary methods: a survey and audiometric testing to assess participants’ hearing abilities. The study included a sample of 50 older workers, all with diagnosed hearing loss. Results: The results of the survey showed that most older workers are regularly exposed to noise at work, which has long-term negative effects on their hearing. This highlights the need to introduce appropriate protective measures such as personal protective equipment, insulation of noise sources, and raising awareness about the dangers of noise. In addition to the questionnaire survey, the analysis of hearing measurements revealed that all respondents had significant bilateral hearing loss, with sensorineural hearing loss being the most prevalent type. Conclusions: This study highlights the negative impact of chronic noise exposure in the workplace on the hearing, communication and productivity of older workers and emphasizes the importance of combining preventive measures, hearing protection and workplace adaptations to promote their well-being and performance. Full article

Background. Parkinson’s Disease (PD) is a neurological condition that can severely impair gait, often through changes to gait parameters including stride length, velocity, and variability. Therapeutic interventions such as Rhythmic Auditory Stimulation (RAS^®) target gait dysfunction in PD by using the regular beat of music or metronome clips to cue normalized walking patterns. Previous research has suggested that auditory cue properties (e.g., familiarity and groove) and individual factors (e.g., beat perception ability and susceptibility to dual-task interference) influence auditory cueing treatment efficacy in healthy young and older adults; however, optimization of rhythmic cueing across individuals with PD remains understudied. Methods. To address this, we explored the effects of familiarity, groove, beat perception ability, and synchronization instructions on gait in patients with PD during accelerated auditory cues. Individuals with idiopathic PD were randomized to walk freely or synchronized to music and metronome cues played 10% faster than their baseline walking cadence. Musical stimuli varied in self-reported familiarity and perceived groove and beat perception ability was assessed to classify participants as good or poor beat perceivers. Results. Overall, high-groove music and synchronized walking elicited faster gait patterns compared to low-groove music and free walking, respectively, as demonstrated by increased gait velocity and cadence. Familiarity and beat perception ability did not significantly affect gait in individuals with PD. Discussion. Altogether, our results indicate that high-groove music and synchronized walking lead to the greatest gait improvements during cueing, regardless of beat perception ability. Conclusion. Future studies and clinical interventions should consider stimulus type and synchronization instructions when implementing cueing therapies for gait dysfunction in PD in order to optimize treatment responses. Full article

Background/Objectives: Waardenburg syndrome (WS) is a genetic disorder characterized by sensorineural hearing loss (SNHL) and pigmentation anomalies. While hearing impairment is a well-established feature of WS, vestibular dysfunction is also reported. This study aimed to investigate vestibular deficits in pediatric WS patients with SNHL, correlating these findings with molecular, audiometric, and radiological data to establish distinct phenotypic profiles for each WS subtype and associated pathogenic variants. Methods: This retrospective study included children with a genetically confirmed diagnosis of WS who underwent vestibular, auditory, and inner ear radiological assessments as part of their routine medical care between July 2000 and May 2022. Data were collected from medical records, including medical history, clinical findings, and assessment results. Results: Vestibular dysfunction was found to be highly prevalent, affecting 64% of the cohort, often impacting the canal sensory organ (89%) and occasionally the otolithic function (33%). Patients with SOX10 pathogenic variations exhibited a markedly higher risk of vestibular dysfunction, highlighting the unique role of SOX10 in inner ear development. Notably, inner ear malformations were identified in all SOX10-mutated subjects, whereas such anomalies were rare among individuals with other WS gene variants, occurring in only two additional cases with minor malformations. Conclusions: This study reveals a significant prevalence of vestibular deficits in pediatric WS patients with SNHL, emphasizing the need for routine vestibular assessments. The higher prevalence and severity of vestibular impairments in SOX10-mutated patients underscore the importance of molecular analysis in clinical diagnosis and management. Full article

Background/Objectives: Huntington’s disease (HD) is a neurodegenerative disorder involving the basal ganglia and is characterized by psychiatric, cognitive, and movement dysfunction, including gait and balance impairment. Given the limited efficacy of pharmacological treatments for HD motor symptoms, nonpharmacological approaches like rhythmic auditory stimulation are being explored. This study aims to describe walking performance in people with HD during rhythmic auditory stimulation using external musical cues and internal singing cues. Methods: Individuals in the manifest stage of HD performed walking in four conditions: (1) comfortable pace, (2) cognitive dual task, (3) musical cue (music was played aloud), and (4) singing cue (participants sang aloud). Sensors measured cadence, velocity, stride length, and variability. Relationships between change in cadence and motor and cognitive measures were explored. Results: While no direct measurements of synchronization were performed, limiting our interpretation, neither the external musical cue nor the singing cue significantly improved walking performance. Both cues increased variability, similar to what was observed during the dual task. Greater subjective balance confidence and better cognitive performance were associated with positive cadence change during cueing. Conclusions: Musical cues may be too cognitively demanding for individuals with Huntington’s disease as they worsen gait variability without increasing gait speed, cadence, or stride length. Although global cognition and perceived balance confidence were related to the ability to increase cadence, very few people were able to increase their cadence during either cue. Therefore, the results do not support the use of musical cues to improve gait for individuals with Huntington’s disease. Full article

Objective: To evaluate the outcomes of a modified infratemporal fossa approach (ITFA) that preserves the posterior external auditory canal (EAC) in patients with tumors in the infratemporal fossa and skull base, focusing on postoperative hearing and facial nerve function. Methods: This retrospective study included nine patients who underwent ITFA with posterior EAC preservation for tumor removal while minimizing facial nerve rerouting. All surgeries were performed by a single surgeon. Preoperative and postoperative hearing levels, facial nerve function, tumor characteristics, and surgical outcomes were analyzed. Air-bone gaps (ABG) were assessed using pure tone audiometry, and facial nerve function was assessed using the House–Brackmann grading system. Results: The cohort consisted of eight female patients and one male patient, with a mean tumor size of 3.0 cm. Surgical outcomes were promising, with no statistically significant increase in postoperative ABG and well-preserved facial nerve function. Only one patient developed postoperative grade II facial palsy. A residual tumor was identified in one case with extensive meningioma, which has remained stable, and no recurrence or regrowth was noted during the follow-up period (mean: 3.7 years). The modified approach minimized complications related to conductive hearing loss and facial nerve dysfunction. Conclusions: The modified ITFA with posterior EAC preservation provides a promising alternative to conventional ITFA for managing deep-seated tumors. It preserves both hearing and facial nerve function while ensuring adequate tumor resection. Full article