Search Results (66)

Background: Cochlear implantation (CI) in pediatric patients with cochlear nerve deficiencies (CND) remains controversial due to a highly variable clinical population, lack of evidence-based guidelines, and mixed research findings. This study assessed current clinical perspectives and practices regarding CI candidacy in children with CND among hearing healthcare professionals in the USA. Methods: An anonymous 19-question online survey was distributed to CI clinicians nationwide. The survey assessed professional background, experience with aplasia and hypoplasia, and perspectives on CI versus auditory brainstem implant (ABI) candidacy, including imaging practices and outcome expectations. Both multiple-choice and open-ended responses were analyzed to identify trends and reasoning. Results: Seventy-two responses were analyzed. Most clinicians supported CI for hypoplasia (60.2%) and, to a lesser extent, for aplasia (41.7%), with audiologists more likely than neurotologists to favor CI. Respondents cited lower risk, accessibility, and the potential for benefit as reasons to attempt CI before ABI. However, many emphasized a case-by-case approach, incorporating imaging, electrophysiological testing, and family counseling. Only 22.2% considered structural factors the best predictors of CI success. Conclusions: Overall, hearing health professionals in the USA tend to favor CI as a first-line option, while acknowledging the limitations of current diagnostic tools and the importance of individualized, multidisciplinary decision-making in CI candidacy for children with CND. Findings reveal a high variability in clinical perspectives on CI implantation for pediatric aplasia and hypoplasia and a lack of clinical consensus, highlighting the need for more standardized assessment and imaging protocols to provide greater consistency across centers and enable the development of evidence-based guidelines. Full article

The assessment of hearing in children is important, as hearing deficits can impair child development. The Auditory Steady-State Response (ASSR) is an electrophysiological technique that is able to simultaneously evaluate both ears at four frequencies, making it advantageous for testing children where the test time needs to be as short as possible. The objective of this work was to perform a literature review on the effectiveness of ASSR to gauge hearing thresholds in babies, infants, and children, examining its ability to distinguish mild hearing loss from normal cases. This review used PubMed, Web of Science, and Scopus databases from 2014 to 2024. A total of 1226 articles were identified, although only 16 met the previously established inclusion criteria. It was found that ASSR is a reliable diagnostic tool for babies, infants, and children. Recent work appears better able to distinguish mild hearing loss from normal hearing. One unresolved aspect that needs additional attention is the effectiveness of using bone-conducted stimuli. Full article

Implementing neonatal hearing screening has significantly reduced the age at which hearing impairments are detected in children. Nevertheless, objective electrophysiological assessments, such as auditory brainstem response (ABR) or auditory steady-state response (ASSR) testing, are often necessary for children older than six months. These evaluations should be conducted while the child is asleep to obtain accurate and interpretable results, as movement and muscle activity can introduce artifacts that compromise the quality of the recordings. In this narrative review, we evaluate sedation strategies in paediatric procedures, focusing on the efficacy, safety, and practicality of agents/routes for inducing sleep during ABR/ASSR testing. Sedation choices should prioritise patient safety, clinical context, and result reliability and be tailored to the individual’s age, health status, and procedural needs. Full article

Background/Objectives: Individuals with similar hearing sensitivity exhibit varying levels of tolerance to background noise, a trait tied to unique individual characteristics that affect their responsiveness to noise reduction (NR) processing in hearing aids. The present study aimed to capture such individual characteristics by employing electrophysiological measures and subjective noise-tolerance profiles, and both were analyzed in relation to speech-in-noise performance and NR outcomes. Methods: From a sample of 42 participants with normal hearing, the neural signal-to-noise ratio (SNR)—a cortical index comparing the amplitude ratio between auditory evoked responses to target speech onset versus noise onset—was calculated, and individual noise-tolerance profiles were also derived using k-means cluster analysis to classify participants into distinct subgroups. Results: The neural SNR showed significant correlations with speech-in-noise performance and NR outcomes with varying strength. In contrast, noise-tolerance subgroups did not show meaningful group-level differences in either speech-in-noise or NR outcomes. The neural SNR and noise-tolerance profiles were found to be statistically independent. Conclusions: While the neural SNR reliably predicted perceptual performance in background noise and NR outcomes, our noise-tolerance profiles lacked sufficient sensitivity. Still, subjective ratings of individual noise tolerance are clinically accessible, and thus, integrating both physiology and subjective measures in the same cohort is a valuable strategy. Full article

Hearing plays a significant role in children’s development. The Auditory Steady State Response (ASSR) using a narrow band CE^® chirp is a technique that allows multiple stimuli to be presented simultaneously, making it possible to obtain electrophysiological thresholds with frequency specificity. The objective of this work is to analyze the findings obtained with the ASSR NB-CE^® chirp technique and compare them with two other methodologies—click ABR and tone-burst ABR—in the audiological assessment of children carried out under inhalation anesthesia. All the exams were performed in a single session. This study involved 71 children aged between 14 and 59 months, male and female, who were referred for ABR and ASSR due to suspected hearing loss and/or delay in speech/language development. Pearson’s correlation coefficient between the uncorrected and corrected thresholds obtained in the three methods demonstrated high correlations for all frequencies evaluated. Full article

Background: Perceptual awareness refers to the conscious detection and identification of a sensory event. In electrophysiological studies, it is associated with a modality-specific negative-going event-related potential, which can be observed as early as 100–300 ms after the stimulus onset. Method: In this study, we measured neuroelectric brain activity during the auditory attentional blink, comparing brain responses when participants correctly reported both the first (T1) and second (T2) targets versus when only T1 was detected, but T2 was missed. To achieve robust statistical power, we pooled data across six previously published studies for the current analyses. Result: Our results revealed that accurately reporting both T1 and T2 elicited greater negativity between 150 and 300 ms over the frontocentral and central scalp areas following T2 onset, compared to trials where T1 was detected but T2 was not. Additionally, a positive displacement, peaking around 800 ms over the central-parietal scalp area, followed the early negativity. Successful detection of both T1 and T2 was also associated with more pronounced alpha suppression, peaking at approximately 500 ms before and 800 ms after T2 onset. Conclusions: These findings suggest that neural correlates of what we refer to “auditory awareness” occur both before the stimulus sequence and soon after T2 onset. Pre-stimulus difference in alpha power may serve as an indicator of lapses in attention, with greater alpha power reflecting periods when participants are less engaged or off-task. Full article

The simultaneous analysis of electrophysiological signals from various physiological systems, such as the brain, skeletal muscles, and cardiac muscles, has become increasingly necessary in both clinical and research settings. However, acquiring multiple modalities of electrophysiological data often necessitates the use of diverse, specialized technological tools, which can complicate the establishment of a comprehensive multimodal experimental setup. This paper introduces a prototype system, named the Multimodal–Multichannel Acquisition Module—MADQ, designed for the simultaneous acquisition of multimodal and multichannel electrophysiological and general-purpose signals. The MADQ comprises three distinct capturing blocks, each equipped with separate reference circuits, supporting a total of up to 40 electrophysiological input channels, alongside 4 channels of analog input and 4 channels of digital input signal. The system is capable of sampling frequencies up to 16 kHz. Key features of the MADQ include individually configurable bipolar recording, lead-off detection capability, and real-time online filtering. The system’s functional performance was characterized through metrics such as Input-Referred Noise (IRN), Noise-Free Bits (NFB), and Effective Number of Bits (ENOB) across varying gain and sampling frequencies. Preliminary experiments, conducted in a setup emulating a sleep study with auditory evoked potential detection, demonstrate the system’s potential for integration into multimodal experimental scenarios. Full article

Background/Objectives: In the early stage of presbycusis, patients experience reduced speech perception in noisy environments despite normal audiometry, normally known as hidden hearing loss. Diagnostic indicators like the reduced amplitude of ABR wave I, elevated extended high-frequency threshold (EHT), and decreased middle ear muscle reflex (MEMR) amplitude aim to identify biomarkers of peripheral auditory pathology but remain inconsistent. Mismatch negativity (MMN) is a cortical auditory evoked potential generated when the brain detects sound changes. This study aimed to assess MMN as a diagnostic tool for hidden hearing loss in adults. Methods: Seventy-three subjects with normal hearing underwent an extended pure-tone audiogram examination ranging from 0.125 to 16 kHz and a subsequent MMN assessment with two different paradigms: a speech (ba/da) and a tone (1/2 kHz) paradigm. The MMN’s amplitude and latency were measured and analyzed. Results: The outcome shows a significant age-related effect on MMN amplitude in the speech condition (χ² = 13.0, p = 0.002). Specifically, the MMN amplitude in the 25–30-year-old group was significantly smaller than in the 20–25-year-old group (p = 0.0015, Cohen’s d = 0.63). Additionally, no further effects of age were observed on the cortical potentials examined. Also, neither tone nor speech paradigms showed a significant influence of EHT on the amplitude or latency of either MMN or P300. Conclusions: The application of MMN as an electrophysiological tool to diagnose hidden hearing loss in normal hearing adults has limitations. However, in contrast to MMN responses to tonal stimuli, the present study reveals that MMN amplitude obtained with speech stimuli may indicate early signs of central auditory deficits. 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

Misophonia is a condition characterized by intense, involuntary distress or anger in response to specific sounds, often leading to irritation or aggression. While the condition is recognized for its emotional and behavioral impacts, little is known about its physiological and perceptual effects. The current study aimed to explore the physiological correlates and perceptual consequences of misophonia through a combination of electrophysiological, perceptual, and cognitive assessments. Seventeen individuals with misophonia and sixteen control participants without the condition were compared. Participants completed a comprehensive battery of tests, including (a) cortical event-related potentials (ERPs) to assess neural responses to standard and deviant auditory stimuli, (b) the spatial release from the speech-on-speech masking (SRM) paradigm to evaluate speech segregation in background noise, and (c) the flanker task to measure selective attention and cognitive control. The results revealed that individuals with misophonia exhibited significantly smaller mean peak amplitudes of the N1 and N2 components in response to oddball tones compared to controls. This suggests a potential underlying neurobiological deficit in misophonia patients, as these components are associated with early auditory processing. However, no significant differences between each group were observed in the P1 and P2 components regarding oddball tones or in any ERP components in response to standard tones. Despite these altered neural responses, the misophonia group did not show differences in hearing thresholds, speech perception abilities, or cognitive function compared to the controls. These findings suggest that while misophonia may involve distinct neurophysiological changes, particularly in early auditory processing, it does not necessarily lead to perceptual deficits in speech perception or cognitive function. Full article

This preliminary study investigates the potential relationship between electrophysiological profiles measured by quantitative electroencephalography (QEEG) and attentional performance in 34 university American football players. QEEG data revealed patterns associated with burnout, chronic pain, and insomnia among the athletes. Attentional performance was generally average, but players exhibited faster reaction times in the alertness task without warning, fewer errors in the sustained attention task, and lower scores in the divided attention task, favoring visual information over auditory information. Significant negative correlations emerged between QEEG profiles associated with burnout, ADHD, depression, and anxiety and specific attentional subcomponents. These findings suggest a link between mental health-related brain activity and attentional performance. In a clinical context, they emphasize the need for early detection and intervention in mental health problems. This might improve cognitive performance and well-being in athletes. However, due to the small sample size and the lack of a control group, these results are considered preliminary, and further research is required to confirm and expand on these associations. Full article

Statistical learning (SL), the ability to extract patterns from the environment, has been assumed to play a central role in whole cognition, particularly in language acquisition. Evidence has been gathered, however, from behavioral experiments relying on simplified artificial languages, raising doubts on the generalizability of these results to natural contexts. Here, we tested if SL is affected by the composition of the speech streams by expositing participants to auditory streams containing either four nonsense words presenting a transitional probability (TP) of 1 (unmixed high-TP condition), four nonsense words presenting TPs of 0.33 (unmixed low-TP condition) or two nonsense words presenting a TP of 1, and two of a TP of 0.33 (mixed condition); first under incidental (implicit), and, subsequently, under intentional (explicit) conditions to further ascertain how prior knowledge modulates the results. Electrophysiological and behavioral data were collected from the familiarization and test phases of each of the SL tasks. Behavior results revealed reliable signs of SL for all the streams, even though differences across stream conditions failed to reach significance. The neural results revealed, however, facilitative processing of the mixed over the unmixed low-TP and the unmixed high-TP conditions in the N400 and P200 components, suggesting that moderate levels of entropy boost SL. Full article

Background: This study investigates electrophysiological distinctions in auditory evoked potentials (AEPs) among individuals with chronic subjective tinnitus, with a specific focus on the impact of treatment response and tinnitus localisation. Methods: Early AEPs, known as Auditory Brainstem Responses (ABR), and middle AEPs, termed Auditory Middle Latency Responses (AMLR), were analysed in tinnitus patients across four clinical centers in an attempt to verify increased neuronal activity, in accordance with the current tinnitus models. Our statistical analyses primarily focused on discrepancies in time–domain core features of ABR and AMLR signals, including amplitudes and latencies, concerning both treatment response and tinnitus laterality. Results: Statistically significant differences were observed in ABR wave III and V latencies, ABR wave III peak amplitude, and AMLR wave Na and Nb amplitudes when comparing groups based on their response to treatment, accompanied by varying effect sizes. Conversely, when examining groups categorised by tinnitus laterality, no statistically significant differences emerged. Conclusions: These results provide valuable insights into the potential influence of treatment responses on AEPs. However, further research is imperative to attain a comprehensive understanding of the underlying mechanisms at play. 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

Background: Chiari malformation is a condition involving caudal descent of the hindbrain which herniates the cerebellar tonsils through the foramen magnum. The purpose of this study was to quantify auditory deficits in an affected individual and to explore the hypothesis that cerebellar malformation specifically disrupts binaural processing. Methods: We present audiometric, electrophysiologic, imaging and auditory perceptual findings for a 17-year-old female with Chiari 1 malformation and for a cohort of 35 hearing- and age-matched controls. Results: The patient presented with auditory deficit consistent with cerebellar disorder—that is, an impaired ability to judge the duration of auditory stimuli. In addition, she showed evidence of abnormal binaural processing affecting her capacity to localise sound sources to optimise speech perception in background noise. The provision of a remote microphone listening device was successful in improving her perceptual ability to normal levels. Conclusions: Despite normal sound detection ability, this child with Chiari 1 malformation suffered functional hearing deficits severe enough to impact everyday listening/communication and educational progress. These limitations were ameliorated through auditory intervention. Full article