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The auditory steady state response (ASSR) arises when periodic sounds evoke stable responses in auditory networks that reflect the acoustic characteristics of the stimuli, such as the amplitude of the sound envelope. Larger for some stimulus rates than others, the ASSR in the human electroencephalogram (EEG) is notably maximal for sounds modulated in amplitude at 40 Hz. To investigate the local circuit underpinnings of the large ASSR to 40 Hz amplitude-modulated (AM) sounds, we acquired skull EEG and local field potential (LFP) recordings from primary auditory cortex (A1) in the rat during the presentation of 20, 30, 40, 50, and 80 Hz AM tones. 40 Hz AM tones elicited the largest ASSR from the EEG acquired above auditory cortex and the LFP acquired from each cortical layer in A1. The large ASSR in the EEG to 40 Hz AM tones was not due to larger instantaneous amplitude of the signals or to greater phase alignment of the LFP across the cortical layers. Instead, it resulted from decreased latency variability (or enhanced temporal consistency) of the 40 Hz response. Statistical models indicate the EEG signal was best predicted by LFPs in either the most superficial or deep cortical layers, suggesting deep layer coordinators of the ASSR. Overall, our results indicate that the recruitment of non-uniform but more temporally consistent responses across A1 layers underlie the larger ASSR to amplitude-modulated tones at 40 Hz.

Previous work assessing the effect of additive noise on the postural control system has found a positive effect of additive white noise on postural dynamics. This study covers two separate experiments that were run sequentially to better understand how the structure of the additive noise signal affects postural dynamics, while also furthering our knowledge of how the intensity of auditory stimulation of noise may elicit this phenomenon. Across the two experiments, we introduced three auditory noise stimulations of varying structure (white, pink, and brown noise). Experiment 1 presented the stimuli at 35 dB while Experiment 2 was presented at 75 dB. Our findings demonstrate a decrease in variability of the postural control system regardless of the structure of the noise signal presented, but only for high intensity auditory stimulation.

Understanding the neural basis of speech perception requires that we study the human brain both at the scale of the fundamental computational unit of neurons and in their organization across the depth of cortex. Here we used high-density Neuropixels arrays1-3 to record from 685 neurons across cortical layers at nine sites in a high-level auditory region that is critical for speech, the superior temporal gyrus4,5, while participants listened to spoken sentences. Single neurons encoded a wide range of speech sound cues, including features of consonants and vowels, relative vocal pitch, onsets, amplitude envelope and sequence statistics. Neurons at each cross-laminar recording exhibited dominant tuning to a primary speech feature while also containing a substantial proportion of neurons that encoded other features contributing to heterogeneous selectivity. Spatially, neurons at similar cortical depths tended to encode similar speech features. Activity across all cortical layers was predictive of high-frequency field potentials (electrocorticography), providing a neuronal origin for macroelectrode recordings from the cortical surface. Together, these results establish single-neuron tuning across the cortical laminae as an important dimension of speech encoding in human superior temporal gyrus.

Older adults must have the ability to walk at variable speeds/distances to meet community demands. This single group pre–post test study's purposes were to examine if actual cadences after 7 weeks of rhythmic auditory stimulation gait training matched target cadences, improved walking distance, duration, velocity, maximum cadence, balance, enjoyment, and/or changed spatial/temporal gait parameters. Fourteen female adults (72.6 ± 4.4 years) participated in 14 sessions, while variable cadences were progressively introduced. Eleven older adult responders walked faster (3.8 steps/min) than one target cadence (−10% pace) while matching the target cadences for the other paces when walking with rhythmic auditory stimulation. Two nonresponders walked near their baseline cadence with little variability while one walked at faster cadences; all three did not appear to adjust to the beat of the music. After training, participants increased their walking distance, 90.8 ± 46.5 m; t(1, 13) = −7.3; p ≤.005, velocity, 0.36 ± 0.15 m/s; t(1, 40) = −15.4; p <.001, and maximum cadence, 20.6 ± 9.1 steps/min; t(1, 40) = −14.6; p <.001; changes exceeded minimal clinically important differences. Twelve of 14 expressed enjoyment. Walk with rhythmic auditory stimulation training is a promising activity for older adults, which may translate to an individual's ability to adapt walking speeds to various community demands. [ABSTRACT FROM AUTHOR]

Observers can discriminate between correct versus incorrect perceptual decisions with feelings of confidence. The centro-parietal positivity build-up rate (CPP slope) has been suggested as a likely neural signature of accumulated evidence, which may guide both perceptual performance and confidence. However, CPP slope also covaries with reaction time, which also covaries with confidence in previous studies, and performance and confidence typically covary; thus, CPP slope may index signatures of perceptual performance rather than confidence per se. Moreover, perceptual metacognition-including neural correlates-has largely been studied in vision, with few exceptions. Thus, we lack understanding of domain-general neural signatures of perceptual metacognition outside vision. Here we designed a novel auditory pitch identification task and collected behavior with simultaneous 32-channel EEG in healthy adults. Participants saw two tone labels which varied in tonal distance on each trial (e.g., C vs D, C vs F), then heard a single auditory tone; they identified which label was correct and rated confidence. We found that pitch identification confidence varied with tonal distance, but performance, metacognitive sensitivity (trial-by-trial covariation of confidence with accuracy), and reaction time did not. Interestingly, however, while CPP slope covaried with performance and reaction time, it did not significantly covary with confidence. We interpret these results to mean that CPP slope is likely a signature of first-order perceptual processing and not confidence-specific signals or computations in auditory tasks. Our novel pitch identification task offers a valuable method to examine the neural correlates of auditory and domain-general perceptual confidence.

Summary Deep sleep oscillations are proposed to be central in restoring brain function and to affect different aspects of motor performance such as facilitating the consolidation of motor sequences resulting in faster and more accurate sequence tapping. Yet, whether deep sleep modulates performance fatigability during fatiguing tasks remains unexplored. We investigated overnight changes in tapping speed and resistance against performance fatigability via a finger tapping task. During fast tapping, fatigability manifests as a reduction in speed (or “motor slowing”) which affects all tapping tasks, including motor sequences used to study motor memory formation. We further tested whether overnight changes in performance fatigability are influenced by enhancing deep sleep oscillations using auditory stimulation. We found an overnight increase in tapping speed alongside a reduction in performance fatigability and perceived workload. Auditory stimulation led to a global enhancement of slow waves and both slow and fast spindles during the stimulation window and a local increase in slow spindles in motor areas across the night. However, overnight performance improvements were not significantly modulated by auditory stimulation and changes in tapping speed or performance fatigability were not predicted by individual changes in deep sleep oscillations. Our findings demonstrate overnight changes in fatigability but revealed no evidence suggesting that this effect is causally linked to temporary augmentation of slow waves or sleep spindles. Our results are important for future studies using tapping tasks to test the relationship between sleep and motor memory consolidation, as overnight changes in objectively measured and subjectively perceived fatigue likely impact behavioural outcomes. [ABSTRACT FROM AUTHOR]

Following the global progressive deployment of 5G networks, considerable attention has focused on assessing their potential impact on human health. This study aims to investigate autonomous nervous system changes by exploring skin temperature and electrodermal activity (EDA) among 44 healthy young individuals of both sexes during and after exposure to 3.5 GHz antenna‐emitted signals, with an electrical field intensity ranging from 1 to 2 V/m. The study employed a randomized, cross‐over design with triple‐blinding, encompassing both ‘real’ and ‘sham’ exposure sessions, separated by a maximum interval of 1 week. Each session comprised baseline, exposure and postexposure phases, resulting in the acquisition of seven runs. Each run initiated with a 150 s segment of EDA recordings stimulated by 10 repeated beeps. Subsequently, the collected data underwent continuous decomposition analysis, generating specific indicators assessed alongside standard metrics such as trough‐to‐peak measurements, global skin conductance and maximum positive peak deflection. Additionally, non‐invasive, real‐time skin temperature measurements were conducted to evaluate specific anatomical points (hand, head and neck). The study suggests that exposure to 3.5 GHz signals may potentially affect head and neck temperature, indicating a slight increase in this parameter. Furthermore, there was a minimal modulation of certain electrodermal metrics after the exposure, suggesting a potentially faster physiological response to auditory stimulation. However, while the results are significant, they remain within the normal physiological range and could be a consequence of an uncontrolled variable. Given the preliminary nature of this pilot study, further research is needed to confirm the effects of 5G exposure. [ABSTRACT FROM AUTHOR]

Objective: The purpose of the present study was to explore the effect of plateau duration in eliciting masseter vestibular evoked myogenic potentials (mVEMPs) in healthy individuals with hearing sensitivity ≤ 15dBHL. Method: A within-subjects design was utilized in the study. Therefore, ipsilateral tone burst evoked mVEMPs were obtained from 30 healthy individuals using the zygomatic montage at 500 Hz tone bursts. Self-monitoring biofeedback was given during the procedure to confirm the tension of the masseter muscle. mVEMPs were recorded across three different plateau duration from 0 to 2 ms with rise/fall time of 2 ms at 95dBnHL. Hence the median and interquartile range were calculated for descriptive analysis of the data followed by non-parametric inferential statistics. Results: Tone burst evoked mVEMPs were found to be 100% present across all three plateau durations for both ears at 95 dBnHL. P11 and N21 latencies increased with longer plateau durations in both ears. There were no significant differences in P11-N21 peak-to-peak amplitude or interaural amplitude ratio (IAAR) observed across different plateau durations. IAAR was lowest for a 2 ms plateau duration in the 2–2-2 cycle. No significant variations were found across the three plateau durations. Conclusion: Significant differences in P11 and N21 latencies were observed across the three stimulus cycles, while no significant differences were found for P11N21 amplitude and IAAR. Yet, there was found to have the highest amplitude and lowest IAAR for 2–2-2 cycle than 2–0-2 and 2–1-2, suggesting it to be the optimal stimulus among the three of them. [ABSTRACT FROM AUTHOR]

Physiological oscillations, such as those involved in brain activity, heartbeat, and respiration, display inherent rhythmicity across various timescales. However, adaptive behavior arises from the interaction between these intrinsic rhythms and external environmental cues. In this study, we used multimodal neurophysiological recordings, simultaneously capturing signals from the central and autonomic nervous systems (CNS and ANS), to explore the dynamics of brain and body rhythms in response to rhythmic auditory stimulation across three conditions: baseline (no auditory stimulation), passive auditory processing, and active auditory processing (discrimination task). Our findings demonstrate that active engagement with auditory stimulation synchronizes both CNS and ANS rhythms with the external rhythm, unlike passive and baseline conditions, as evidenced by power spectral density (PSD) and coherence analyses. Importantly, phase angle analysis revealed a consistent alignment across participants between their physiological oscillatory phases at stimulus or response onsets. This alignment was associated with reaction times, suggesting that certain phases of physiological oscillations are spontaneously prioritized across individuals due to their adaptive role in sensorimotor behavior. These results highlight the intricate interplay between CNS and ANS rhythms in optimizing sensorimotor responses to environmental demands, suggesting a potential mechanism of embodied predictive processing. [ABSTRACT FROM AUTHOR]

The ventral posterolateral nucleus (VPL), being categorized as the first‐order thalamic nucleus, is considered to be dedicated to uni‐modal somatosensory processing. Cross‐modal sensory interactions on thalamic reticular nucleus cells projecting to the VPL, on the other hand, suggest that VPL cells are subject to cross‐modal sensory influences. To test this possibility, the effects of auditory or visual stimulation on VPL cell activities were examined in anaesthetized rats, using juxta‐cellular recording and labelling techniques. Recordings were obtained from 70 VPL cells, including 65 cells responsive to cutaneous electrical stimulation of the hindpaw. Auditory or visual alone stimulation did not elicit cell activity except in three bi‐modal cells and one auditory cell. Cross‐modal alterations of somatosensory response by auditory and/or visual stimulation were recognized in 61 cells with regard to the response magnitude, latency (time and jitter) and/or burst spiking properties. Both early (onset) and late responses were either suppressed or facilitated, and de novo cell activity was also induced. Cross‐modal alterations took place depending on the temporal interval between the preceding counterpart and somatosensory stimulations, the intensity and frequency of sound. Alterations were observed mostly at short intervals (< 200 ms) and up to 800 ms intervals. Sounds of higher intensities and lower frequencies were more effective for modulation. The susceptibility to cross‐modal influences was related to cell location and/or morphology. These and previously reported similar findings in the auditory and visual thalamic nuclei suggest that cross‐modal sensory interactions pervasively take place in the first‐order sensory thalamic nuclei. [ABSTRACT FROM AUTHOR]

Objective: The ability to discriminate natural soundscapes recorded in a temperate terrestrial biome was measured in 15 hearing-impaired (HI) listeners with bilateral, mild to severe sensorineural hearing loss and 15 normal-hearing (NH) controls. Design: Soundscape discrimination was measured using a three-interval oddity paradigm and the method of constant stimuli. On each trial, sequences of 2-second recordings varying the habitat, season and period of the day were presented diotically at a nominal SPL of 60 or 80 dB. Results: Discrimination scores were above chance level for both groups, but they were poorer for HI than NH listeners. On average, the scores of HI listeners were relatively well accounted for by those of NH listeners tested with stimuli spectrally-shaped to match the frequency-dependent reduction in audibility of individual HI listeners. However, the scores of HI listeners were not significantly correlated with pure-tone audiometric thresholds and age. Conclusions: These results indicate that the ability to discriminate natural soundscapes associated with changes in habitat, season and period of the day is disrupted but it is not abolished. The deficits of the HI listeners are partly accounted for by reduced audibility. Supra-threshold auditory deficits and individual listening strategies may also explain differences between NH and HI listeners. [ABSTRACT FROM AUTHOR]

Introduction: Auditory deficiencies have profound implications for the development of communication abilities, social exchange, and cognitive skills. Although advances in technological instrumentation have decreased the age at which it is possible to detect auditory deficits, an absence of electrophysiological or behavioural reaction to sound does not always reflect auditory loss in younger children. Aim of the study: To profile audiological findings of a child with auditory maturation delay associated with Chudley McCullough Syndrome post auditory stimulation. Method: An extensive audiological evaluation, comprising Behavioral Observation Audiometry, Immittance Audiometry, Oto- Acoustic emission, Auditory Brainstem Response, and Cortical Auditory Evoked Potentials, was performed on a 6-month-old infant. After the audiological evaluation, the infant received auditory stimulation for two months. A comparable audiological assessment was conducted after auditory training. Results: The infant was diagnosed to have severe to profound hearing loss in both ears with noticeable cochlear microphonics in ABR on pre stimulation testing. As a result, he was recommended and had undergone auditory stimulation for two months. Audiological testing post auditory stimulation revealed significant improvements in auditory responses and noticeable betterment in auditory thresholds. Conclusion: Detailed audiological test battery is necessary in determining auditory maturation delay. Intensive auditory stimulation should be provided before concluding on the auditory management. [ABSTRACT FROM AUTHOR]

Purpose: The auditory brainstem response (ABR) can be elicited by broadband stimuli such as the click and chirp. Differences in the click- and chirp-evoked ABR have been extensively described using subjective analyses. The aim of the current research is to determine if subjectively observed differences between the click- and chirp-evoked ABR are also represented in objective signal-tonoise ratio (SNR) measurements obtained from these responses at different stimulus intensities and sweep counts. Method: ABRs were collected using click and chirp stimuli on nine adults with normal hearing sensitivity. Three SNR methods (split-sweep average--based SNR [SSA-SNR], F ratio--based single-point [Fsp], and multipoint [Fmp]) were used for the objective analysis of the waveforms at four stimulus intensities (20, 40, 60, and 80 dB nHL) and five sweep counts (100, 200, 300, 400, and 500 sweeps). Results: SSA-SNR measurements were statistically stronger for chirp- as compared to click-evoked ABRs. Additionally, chirp/click SSA-SNR, Fsp, and Fmp ratio measurements were consistently greater than 1. The advantage associated with the chirp was most noticeable at moderate stimulus intensities for all three measurements. Discussion: The advantages for the chirp observed here could have implications for threshold estimation and screening ABR tests. Furthermore, when stimulus intensity and sweep count were varied, general response trends suggest that the three SNR-based methods performed similarly to each other, as well as to traditionally used subjective measures, suggesting that these techniques have the potential to be used effectively in clinic. [ABSTRACT FROM AUTHOR]

Introduction: Auditory deficiencies have profound implications for the development of communication abilities, social exchange, and cognitive skills. Although advances in technological instrumentation have decreased the age at which it is possible to detect auditory deficits, an absence of electrophysiological or behavioural reaction to sound does not always reflect auditory loss in younger children. Aim of the study: To profile audiological findings of a child with auditory maturation delay associated with Chudley McCullough Syndrome post auditory stimulation. Method: An extensive audiological evaluation, comprising Behavioral Observation Audiometry, Immittance Audiometry, Oto- Acoustic emission, Auditory Brainstem Response, and Cortical Auditory Evoked Potentials, was performed on a 6-month-old infant. After the audiological evaluation, the infant received auditory stimulation for two months. A comparable audiological assessment was conducted after auditory training. Results: The infant was diagnosed to have severe to profound hearing loss in both ears with noticeable cochlear microphonics in ABR on pre stimulation testing. As a result, he was recommended and had undergone auditory stimulation for two months. Audiological testing post auditory stimulation revealed significant improvements in auditory responses and noticeable betterment in auditory thresholds. Conclusion: Detailed audiological test battery is necessary in determining auditory maturation delay. Intensive auditory stimulation should be provided before concluding on the auditory management. [ABSTRACT FROM AUTHOR]

Noise adaptation is the improvement in auditory function as the signal of interest is delayed in the noise. Here, we investigated if noise adaptation occurs in spectral, temporal, and spectrotemporal modulation detection as well as in speech recognition. Eighteen normal-hearing adults participated in the experiments. In the modulation detection tasks, the signal was a 200ms spectrally and/or temporally modulated ripple noise. The spectral modulation rate was two cycles per octave, the temporal modulation rate was 10 Hz, and the spectrotemporal modulations combined these two modulations, which resulted in a downward-moving ripple. A control experiment was performed to determine if the results generalized to upward-moving ripples. In the speech recognition task, the signal consisted of disyllabic words unprocessed or vocoded to maintain only envelope cues. Modulation detection thresholds at 0 dB signal-to-noise ratio and speech reception thresholds were measured in quiet and in white noise (at 60 dB SPL) for noise-signal onset delays of 50 ms (early condition) and 800 ms (late condition). Adaptation was calculated as the threshold difference between the early and late conditions. Adaptation in word recognition was statistically significant for vocoded words (2.1 dB) but not for natural words (0.6 dB). Adaptation was found to be statistically significant in spectral (2.1 dB) and temporal (2.2 dB) modulation detection but not in spectrotemporal modulation detection (downward ripple: 0.0 dB, upward ripple: −0.4 dB). Findings suggest that noise adaptation in speech recognition is unrelated to improvements in the encoding of spectrotemporal modulation cues. [ABSTRACT FROM AUTHOR]

Novel stimulation methods are needed to overcome the limitations of contemporary cochlear implants. Optogenetics is a technique that confers light sensitivity to neurons via the genetic introduction of light-sensitive ion channels. By controlling neural activity with light, auditory neurons can be activated with higher spatial precision. Understanding the behaviour of opsins at high stimulation rates is an important step towards their translation. To elucidate this, we compared the temporal characteristics of auditory nerve and inferior colliculus responses to optogenetic, electrical, and combined optogenetic-electrical stimulation in virally transduced mice expressing one of two channelrhodopsins, ChR2-H134R or ChIEF, at stimulation rates up to 400 pulses per second (pps). At 100 pps, optogenetic responses in ChIEF mice demonstrated higher fidelity, less change in latency, and greater response stability compared to responses in ChR2-H134R mice, but not at higher rates. Combined stimulation improved the response characteristics in both cohorts at 400 pps, although there was no consistent facilitation of electrical responses. Despite these results, day-long stimulation (up to 13 h) led to severe and non-recoverable deterioration of the optogenetic responses. The results of this study have significant implications for the translation of optogenetic-only and combined stimulation techniques for hearing loss. [ABSTRACT FROM AUTHOR]

Summary The autonomic nervous system regulates cardiovascular activity during sleep, likely impacting cardiovascular health. Aging, a primary cardiovascular risk factor, is associated with cardiac autonomic disbalance and diminished sleep slow waves. Therefore, slow waves may be linked to aging, autonomic activity and cardiovascular health. However, it is unclear how sleep and slow waves are linked to cardiac autonomic profiles across multiple nights in older adults. We conducted a randomized, crossover trial involving healthy adults aged 62–78 years. Across 2 weeks, we applied auditory stimulation to enhance slow waves and compared it with a SHAM period. We measured sleep parameters using polysomnography and derived heart rate, heart rate variability approximating parasympathetic activity, and blood pulse wave approximating sympathetic activity from a wearable. Here, we report the results of 14 out of 33 enrolled participants, and show that heart rate, heart rate variability and blood pulse wave within sleep stages differ between the first and second half of sleep. Furthermore, baseline slow‐wave activity was related to cardiac autonomic activity profiles during sleep. Moreover, we found auditory stimulation to reduce heart rate variability, while heart rate and blood pulse wave remained unchanged. Lastly, within subjects, higher heart rate coincided with increased slow‐wave activity, indicating enhanced autonomic activation when slow waves are pronounced. Our study shows the potential of cardiac autonomic markers to offer insights into participants' baseline slow‐wave activity when recorded over multiple nights. Furthermore, we highlight that averaging cardiac autonomic parameters across a night may potentially mask dynamic effects of auditory stimulation, potentially playing a role in maintaining a healthy cardiovascular system. [ABSTRACT FROM AUTHOR]

Summary Boosting slow‐wave activity (SWA) by modulating slow waves through closed‐loop auditory stimulation (CLAS) might provide a powerful non‐pharmacological tool to investigate the link between sleep and neurodegeneration. Here, we established mouse CLAS (mCLAS)‐mediated SWA enhancement and explored its effects on sleep deficits in neurodegeneration, by targeting the up‐phase of slow waves in mouse models of Alzheimer's disease (AD, Tg2576) and Parkinson's disease (PD, M83). We found that tracking a 2 Hz component of slow waves leads to highest precision of non‐rapid eye movement (NREM) sleep detection in mice, and that its combination with a 30° up‐phase target produces a significant 15–30% SWA increase from baseline in wild‐type (WTAD) and transgenic (TGAD) mice versus a mock stimulation group. Conversely, combining 2 Hz with a 40° phase target yields a significant increase ranging 30–35% in WTPD and TGPD mice. Interestingly, these phase‐target‐triggered SWA increases are not genotype dependent but strain specific. Sleep alterations that may contribute to disease progression and burden were described in AD and PD lines. Notably, pathological sleep traits were rescued by mCLAS, which elicited a 14% decrease of pathologically heightened NREM sleep fragmentation in TGAD mice, accompanied by a steep decrease in microarousal events during both light and dark periods. Overall, our results indicate that model‐tailored phase targeting is key to modulate SWA through mCLAS, prompting the acute alleviation of key neurodegeneration‐associated sleep phenotypes and potentiating sleep regulation and consolidation. Further experiments assessing the long‐term effect of mCLAS in neurodegeneration may majorly impact the establishment of sleep‐based therapies. [ABSTRACT FROM AUTHOR]

Objective: Auditory hallucinations are the most frequently occurring psychotic symptom in schizophrenia. Continuous theta burst stimulation (cTBS) has been used as an adjuvant treatment for auditory hallucinations. This meta-analysis focused on randomized controlled clinical trials (RCTs) to assess the efficacy of adjuvant cTBS on auditory hallucinations in schizophrenia. Methods: We performed a comprehensive search of four international databases from their inception to January 14, 2024, to identify relevant RCTs that assessed the effects of adjuvant cTBS on auditory hallucinations. The key words included "auditory hallucinations", "continuous theta burst stimulation" and "transcranial magnetic stimulation". Inclusion criteria included patients with auditory hallucinations in schizophrenia or schizoaffective disorder. The Revised Cochrane risk-of-bias tool for randomized trials (RoB1) were used to evaluate the risk of bias and the Review Manager Software Version 5.4 was employed to pool the data. Results: A total of 4 RCTs involving 151 patients with auditory hallucinations were included in the analysis. The Cochrane risk of bias of these studies presented "low risk" in all items. Preliminary analysis showed no significant advantage of adjuvant cTBS over sham stimulation in reducing hallucinations [4 RCTs, n = 151; SMD: - 0.45 (95%CI: -1.01, 0.12), P = 0.13; I2 = 61%]. Subgroup analysis revealed that patients treated with adjuvant cTBS for more than 10 stimulation sessions and total number of pulses more than 6000 [3 RCTs, n = 87; SMD: -4.43 (95%CI: -8.22, - 0.63), P=0.02; I2 = 47%] had a statistically significant improvement in hallucination symptoms. Moreover, the rates of adverse events and discontinuation did not show any significant difference between the cTBS and sham group. Conclusions: Although preliminary analysis did not revealed a significant advantage of adjuvant cTBS over sham stimulation, subgroup analysis showed that specific parameters of cTBS appear to be effective in the treatment of auditory hallucinations in schizophrenia. Further large-scale studies are needed to determine the standard protocol of cTBS for treating auditory hallucinations. [ABSTRACT FROM AUTHOR]

Auditory steady-state response (ASSR) is the result of the brain's ability to follow and entrain its oscillatory activity to the phase and frequency of periodic auditory stimulation. Gamma-band ASSR has been increasingly investigated with intentions to apply it in neuropsychiatric disorders diagnosis as well as in brain–computer interface technologies. However, it is still debatable whether attention can influence ASSR, as the results of the attention effects of ASSR are equivocal. In our study, we aimed to systemically review all known articles related to the attentional modulation of gamma-band ASSRs. The initial literature search resulted in 1283 papers. After the removal of duplicates and ineligible articles, 49 original studies were included in the final analysis. Most analyzed studies demonstrated ASSR modulation with differing attention levels; however, studies providing mixed or non-significant results were also identified. The high versatility of methodological approaches including the utilized stimulus type and ASSR recording modality, as well as tasks employed to modulate attention, were detected and emphasized as the main causality of result inconsistencies across studies. Also, the impact of training, inter-individual variability, and time of focus was addressed. [ABSTRACT FROM AUTHOR]

In Korean, voiced oral stops can occur intervocalically as allophones of their voiceless lenis counterparts; they can also occur initially as variants of nasal stops as a result of initial denasalization (e.g., /motu/→[ b o d u] "all"). However, neither [ŋ] nor [ɡ] (the denasalized variant of the velar nasal) is allowed in the initial position due to the phonotactic restriction against initial [ŋ] in Korean. Given the distribution of nasal and voiced stops in Korean, this study draws on the idea of cue informativeness, exploring (a) whether Korean listeners' attention to nasality and voicing cues is based on the distributional characteristics of nasal and voiced stops, and (b) whether their attention can be generalized across different places of articulation without such linguistic experience. In a forced-choice identification experiment, Korean listeners were more likely than Taiwanese listeners to perceive items on the voiced oral-to-nasal stop continua as nasal when they occurred in the initial position than in the intervocalic position, with the exception of velar stops. The results demonstrate that the Korean listeners attended to the nasality cue more reliably in the medial position than in the initial position, since the nasality cue in this position is less informative due to initial denasalization. Two additional forced-choice identification experiments suggested that upon hearing initial velar nasal [ŋ], Korean listeners variably employed different perceptual strategies (i.e., vowel insertion and place change) to repair the phonotactic illegality. These findings provide support for exemplar models of speech perception in which cue attention is specific to the position of a word, and to segments rather than to features. [ABSTRACT FROM AUTHOR]

Sound symbolism is a non-arbitrary mapping between phonetic properties and meanings. The existence and nature of sound symbolism have long been the subject of empirical research. It is rarely recognized, however, that participants' intrinsic characteristics (e.g., age, gender, language knowledge), in addition to the commonly studied phonetic features, may also influence size ratings. Our study aims to empirically investigate the impact of participant-specific characteristics on size ratings: It also aims to examine whether these characteristics have a direct impact when considering the impact of phonetic features or they rather modify the effects of phonetic features. The current research reports a novel analysis of a previously published dataset with new research questions and previously unused (participant-specific) data. We show that (a) the participants' characteristics did not affect overall size ratings; however, (b) in some cases, they modify (intensify or weaken but do not reverse) the effect of phonetic features on size ratings. Our results emphasize a more comprehensive treatment of sound symbolism, one that considers not only phonetic but also non-phonetic factors in sound symbolism research. [ABSTRACT FROM AUTHOR]

Imagery training, specifically visual and kinesthetic imagery training, is a well-established method of increasing performance in sport. However, some athletes may have impoverished imagery abilities (e.g., aphantasia; low visual imagery) which may hinder performance increments that benefit others. We administered the Plymouth Sensory Imagery Questionnaire (Psi-Q) which tests multisensory imagery, to 329 participants from nine different sports across two levels: semiprofessional and professional. This formed the baseline test, finding no significant differences between sport or level for imagery ability. The Psi-Q located 27 low imagers (mean total scores <4.2/10), including seven non-visual imagers, three non-auditory, seven non-olfactory, and five non-gustatory imagers, and one across all senses. We split the sample randomly into two groups and immediately delivered the imagery intervention, Functional Imagery Training (FIT) to the first group (over two weeks), followed by delivering the same intervention to the wait group. A wait period was due to the lengthy delivery time of the personalized intervention. Both groups received the intervention for the same duration ending in a Psi-Q retest after the intervention. In both groups, FIT increased overall imagery scores which was maintained six months after intervention completion. This indicates that imagery can be trained and maintained in those with a low ability. Follow up interviews (n = 22) explored how imagery was being used beyond the intervention, revealing that the majority now use imagery to plan and manage thinking. Recommendations are given for ways to train imagery in an applied sport setting and future research in broader areas is detailed. Lay summary: We identified 27 individuals with low multi-sensory imagery scores, and used Functional Imagery Training (FIT) to produce enduring improvements in imagery ability, positioning FIT as a valuable tool for enhancing cognitive skills in sports. IMPLICATIONS FOR PRACTICE: Those working with athletes should assess imagery ability and build a personalized strategy that supports learning. To effectively cater to a diverse range of athletes with varying imagination and planning styles, coaches may find it necessary to adapt their communication styles accordingly. Functional Imagery Training (FIT) is an effective method for improving imagery abilities, offering a viable intervention for athletes with impoverished sensory imagery, including aphantasia or low visual imagery. [ABSTRACT FROM AUTHOR]

Purpose: The primary objective of this study was to assess how age influences masseter vestibular evoked myogenic potential (mVEMP) parameters by utilizing 500-Hz tone burst stimuli delivered through air conduction. Method: The study involved 110 participants ranging from 15 to 60 years of age, grouped into five categories, all of whom had no previous issues related to their vestibular system. The participants were exposed to 500-Hz tone burst stimuli at 125 dB SPL through ER-3A inserts. These stimuli were presented to one ear at a time, with alternating polarity. A Tukey's honestly significant difference test was conducted to compare rectified and unrectified amplitude, along with latencies (P11 and N21) and the asymmetric ratio across all age groups. Additionally, a multivariate analysis of variance was performed to assess the impact of sex on the study variables. Results: All 110 participants (220 ears) in the study provided mVEMP responses, encompassing 100% of the subjects. The results revealed a significant reduction in both amplitude and latency extension for the P11 and N21 peaks. Interestingly, P11 latency was also prolonged in the youngest participants (Group 1), suggesting ongoing maturation of the system even beyond the age of 16 years. Moreover, a significant sex difference was observed in the P11 latencies. However, there were no substantial sex differences (p >.05)inN1peaklatency,peak-to- peak amplitude, rectified amplitude, and asymmetric ratio. Conclusions: Changes in structure occur due to degeneration, and the quantity of vestibular sensory hair cells gradually diminishes with age. The rate of decline is faster in semicircular canals compared to end organs, as observed by Merchant et al. (2000). Following a linear degeneration starting at the age of 40 years, a continuous reduction in sensory cells and primary neurons takes place until approximately 40% of vestibular sensory cells are lost by the age of 75 years and insufficient maturation can lead to prolonged peaks and reduced amplitudes compared with those that are considered normal. Therefore, it is crucial to consider the age of the participants when making diagnoses and incorporate relevant correction factors based on age-related reference data. [ABSTRACT FROM AUTHOR]

Purpose: Most modern hearing aids (HAs) employ wide dynamic range compression (WDRC) and noise reduction (NR) algorithms. It is known that the non-linear effects of WDRC and NR cause changes to the output signal-to-noise ratio (SNR) of an HA. However, the relative contributions of WDRC and NR to the nonlinear effects are not fully understood. The current study investigated (a) whether WDRC or NR dominates the nonlinear effects measured at the output of a digital HA and (b) whether the electroacoustic effectiveness of NR depends on WDRC parameters while input SNR and background noise are systematically varied. Method: Test stimuli were Connected Speech Test sentences in multitalker babble noise (2- or 20-talker), presented at input SNRs ranging from -10 to +10 dB. The HA was programmed using multiband WDRC set according to the National Acoustic Laboratories for Nonlinear HA fitting formula 2 prescriptive fits for four standard audiograms and two compression speeds. The NR algorithm of the HA was switched on or off in separate conditions. Nonlinear electroacoustic effects from the WDRC and NR algorithms were assessed by measuring the output SNR of the HA using a phase-inversion technique. To investigate whether there are other factors that may be important besides the output SNR, the Hearing Aid Speech Intelligibility Index and the Hearing Aid Speech Quality Index were applied to the recordings to generate inferences on aided speech intelligibility and perceived speech quality. Results: Results showed that WDRC dominated the net nonlinear effect at low-input SNRs, and the net nonlinear effect of WDRC and NR was reduced at high-input SNRs. Results also showed that the effectiveness of NR depended on compression parameters. The effectiveness of NR was partially explained by the trend of Hearing Aid Speech Intelligibility Index and Hearing Aid Speech Quality Index scores, potentially indicating that the Hearing Aid Speech Intelligibility Index and Hearing Aid Speech Quality Index scores may capture factors that cannot be captured by the output SNR metric. Conclusions: Results suggest that the individual signal-processing stages in an HA should not be considered as independent. Electroacoustic evaluation of WDRC and NR algorithms in isolation is not sufficient to capture the combined nonlinear effect of the two algorithms. Supplemental Material: https://doi.org/10.23641/asha.25962541 [ABSTRACT FROM AUTHOR]

Purpose: The Minimum Speech Test Battery (MSTB) for adults was introduced in 1996 (Nilsson et al., 1996) and subsequently updated in 2011 (Advanced-Bionics et al., 2011). The MSTB has been widely used by clinicians as a guide for cochlear implant (CI) candidacy evaluations and to document post-operative speech recognition performance. Due to changes in candidacy over the past 10 years, a revision to the MSTB was needed. Method: In 2022, the Institute for Cochlear Implant Training (ICIT) recruited a panel of expert CI audiologists to update and revise the MSTB. This panel utilized a modified Delphi consensus process to revise the test battery and to improve its applicability considering recent changes in CI care. Results: This resulted in the MTSB--Version 3 (MSTB-3), which includes test protocols for identifying not only traditional CI candidates but also possible candidates for electric--acoustic stimulation and patients with single-sided deafness and asymmetric hearing loss. The MSTB-3 provides information that supplements the earlier versions of the MSTB, such as recommendations of when to refer patients for a CI, recommended patient-reported outcome measures, considerations regarding the use of cognitive screeners, and sample report templates for clinical documentation of pre- and post-operative care. Electronic versions of test stimuli, along with all the materials described above, will be available to clinicians via the ICIT website (https://www.cochlearimplanttraining.com). Conclusion: The goal of the MSTB-3 is to be an evidence-based test battery that will facilitate a streamlined standard of care for adult CI candidates and recipients that will be widely used by CI clinicians. [ABSTRACT FROM AUTHOR]

Objective: To examine whether the responsiveness of young children to simple sounds was associated with entertainment screen time (EST), opportunities for social interaction, and social and communication skills. Design: Parents completed a questionnaire covering, for years one and two, the number of times the child met with other children; the number of words the child spoke; and the daily amount of EST. Social, attention and communication skills were assessed. Study sample: Participants were 118 children, aged 15 to 46 months. They were initially assessed behaviourally using simple sounds. Children who responded to such sounds were denoted the Responsive group. Children who did not were assessed using familiar songs and denoted the Unresponsive group. Results: The two groups did not differ significantly in mean age or the number of opportunities to meet other children. The Unresponsive group had significantly fewer words than the Responsive group at 12 and 24 months and had significantly higher EST than the Responsive group for years 1 and 2. The Unresponsive group showed lower social, attention and communication skills than the Responsive group. Conclusions: High EST was associated with poorer auditory and social skills. Hence, it may be wise to limit the EST of young children. [ABSTRACT FROM AUTHOR]

Objective: The goal of this study was to determine open field stapedius reflex thresholds (oSRTs) in CI patients with fittings based on subjective loudness ratings. A further objective was to compare these oSRTs and those of eSRT-based fittings that are similar to the oSRTs of normal hearing. Design: Impedance measurements of the ear drum were taken while subjects were wearing their audio processors. The stapedius reflex was elicited by electrical stimulation transmitted through the activated CI system in response to an acoustic stimulus presented in the free sound field. Study sample: Subjects were 50 experienced CI users (n = 57 ears) with CI fittings based on subjective loudness scaling. Results: A reference range for the oSRTs was defined that was identified in CI patients with eSRT-based fittings. Sound levels for stapedius reflex detection were inside the reference target range in 70% of the cases, below the reference range (i.e. down to 40 dB HL) in 20% of the cases, and above the reference range in 10% of the cases. Conclusion: Stapedius reflex detection in a free sound field may help detect fittings with too high or too low stimulation levels that might reduce audiological performance. [ABSTRACT FROM AUTHOR]

Objective: Hearing disorders are common among music professionals, as they are frequently exposed to sound levels exceeding 100 dB(A). By assessing auditory fatigue, situations that are deleterious for hearing could be identified, allowing the deployment of preventive measures before permanent impairment occurs. However, little is known about the factors contributing to auditory fatigue. The objective is to determine the exposure parameters most influencing auditory fatigue during occupational exposure to amplified music. Design: Auditory fatigue was defined as variations of both pure tone auditory (ΔPTA) and efferent reflex thresholds (ΔER) during the workday. Noise exposure was monitored and information on the volunteers was gathered using a questionnaire. Study sample: The population consisted of 43 adult volunteers exposed to amplified music (sound, light or stage technicians, security agents, barmen) and 24 unexposed administrative agents. Results: ΔPTA and ΔER were positively correlated with the energy of noise exposure and its stability over time, i.e a steady noise tends to create more auditory fatigue. Conclusion: In addition to a global decrease of music levels and a systematic use of hearing protection, our results advocate for the provision of quiet periods within noise exposures as they reduce auditory fatigue accumulation and long-term risks for hearing. [ABSTRACT FROM AUTHOR]

Agrammatic aphasia poses challenges in assessing grammatical abilities due to language comprehension difficulties. The suitability of sMMN as an indicator of syntactic processing abilities in these individuals remains uncertain. Two ERP experiments were conducted to investigate whether early syntactic mismatch negativity (sMMN) could assess the syntactic processing ability of Chinese-speaking individuals with agrammatic aphasia. Prior to the ERP experiments, the Western Aphasia Battery (WAB) and the Northwestern Assessment of Verbs and Sentences-Chinese (NAVS-C) were used to screen people with agrammatism. ERP data were collected for both the agrammatic group (AG) (n = 12) and the control group (CG) (n = 12). The first experiment (Experiment 1) involved a passive tone oddball task to control for the influence of primary sound perception. The second experiment (Experiment 2: experiment 2a and experiment 2b) investigated syntactic processing through a passive speech oddball task. Experiment 2a examined the processing of correct sentences and syntactic violation sentences in context. In contrast, Experiment 2b assessed well-formed sequences and ill-formed sequences out of context. The results revealed that frontocentral distributed acoustic MMNs were recorded for the CG between 176 - 196ms in Experiment 1, but not for the AG. In Experiment 2, during the 143 - 173ms window, the left anterior sMMN was exclusively observed for the CG, while the left posterior sMMN was specific to the AG. Furthermore, the amplitudes of the left posterior sMMN (143-173ms) were found to have a negative correlation with scores on sentence comprehension tests: the more negative the sMMN, the lower the scores of people with agrammatic aphasia. Notably, this left posterior MMN was absent in Experiment 1. The early posterior sMMN, discovered for the first time in our study, appears to be more sensitive in detecting syntactic processing impairments in agrammatics compared to the early anterior sMMN. This finding has the potential to enhance the precision of aphasia assessment. [ABSTRACT FROM AUTHOR]

Rhythm is essential in early music education. To acquire rhythm abilities, the synchronisation between body and rhythm patterns is fundamental. Extensive research has shown the link between the auditory-motor system and rhythm acquisition; however, other sensorimotor systems also improve rhythm skills. Rhythm acquisition can be trained using new technologies, such as video games; however, most of these use mainly auditory stimuli to improve it. Therefore, in this work, we explore tactile stimuli to improve rhythm skills using a video game and how visual elements affect rhythm perception using different stimuli. We evaluate and compare the synchronisation of 27 participants following either vibrotactile or auditory stimuli emitted through a rhythm video game in two difficulty levels and we evaluated the user experience. Consistent with the literature, our results indicate that participants synchronised slightly better using auditory than vibrotactile stimuli and players' performance was better when they had visual guides. A fatigue effect persisted and increased over playtime in both conditions. In the current study, usability measures indicate no significant differences. These findings suggest that vibrotactile stimuli are also suitable to train rhythm skills in a video game environment and the game-elements play an important role in players' performance. [ABSTRACT FROM AUTHOR]

Converging evidence suggests a facilitation effect of multisensory interactions on memory performance, reflected in higher accuracy or faster response time under a bimodal encoding condition than a unimodal condition. However, relatively little attention has been given to the effect of multisensory competition on memory. The present study adopted an adaptive staircase test to measure the point of subjective simultaneity (PSS), combined with a delayed matched-to-sample (DMS) task to probe the effect of audiovisual competition during the encoding stage on subsequent unisensory retrieval. The results showed that there was a robust visual dominance effect and multisensory interference effect in WM retrieval, regardless of the subjective synchronous or subjective asynchronous audiovisual presentation. However, a weakened visual dominance effect was observed when the auditory stimulus was presented before the visual stimulus in the encoding period, particularly in the semantically incongruent case. These findings revealed that the prior-entry of sensory information in the early perceptual stage could affect the processing in the late cognitive stage to some extent, and supported the evidence that there is a persistent advantage for visuospatial sketchpad in multisensory WM. [ABSTRACT FROM AUTHOR]

Background and Hypothesis N -Methyl- d -aspartate receptor (NMDA-R) hypofunctioning has been hypothesized to be involved in circuit dysfunctions in schizophrenia (ScZ). Yet, it remains to be determined whether the physiological changes observed following NMDA-R antagonist administration are consistent with auditory gamma-band activity in ScZ which is dependent on NMDA-R activity. Study Design This systematic review investigated the effects of NMDA-R antagonists on auditory gamma-band activity in preclinical (n  = 15) and human (n  = 3) studies and compared these data to electro/magneto-encephalographic measurements in ScZ patients (n  = 37) and 9 studies in early-stage psychosis. The following gamma-band parameters were examined: (1) evoked spectral power, (2) intertrial phase coherence (ITPC), (3) induced spectral power, and (4) baseline power. Study Results Animal and human pharmacological data reported a reduction, especially for evoked gamma-band power and ITPC, as well as an increase and biphasic effects of gamma-band activity following NMDA-R antagonist administration. In addition, NMDA-R antagonists increased baseline gamma-band activity in preclinical studies. Reductions in ITPC and evoked gamma-band power were broadly compatible with findings observed in ScZ and early-stage psychosis patients where the majority of studies observed decreased gamma-band spectral power and ITPC. In regard to baseline gamma-band power, there were inconsistent findings. Finally, a publication bias was observed in studies investigating auditory gamma-band activity in ScZ patients. Conclusions Our systematic review indicates that NMDA-R antagonists may partially recreate reductions in gamma-band spectral power and ITPC during auditory stimulation in ScZ. These findings are discussed in the context of current theories involving alteration in E/I balance and the role of NMDA hypofunction in the pathophysiology of ScZ. [ABSTRACT FROM AUTHOR]

• Enhanced normalized EEG power was observed during ITd than during both WN and BB. • ITd modulated neural oscillation compared in alpha and beta frequency bands. • Changes in brain activity induced by ITd persist for minutes after stimulation. Auditory beats stimulation (ABS) has received increased attention for its potential to modulate neural oscillations through a phenomenon described as brain entrainment (i.e synchronization of brain's electrocortical activity to external stimuli at a specific frequency). Recently, a new form of ABS has emerged, inspired by isochronic tones stimulation (IT d). This study investigated neural oscillatory responses induced by IT d in comparison with formerly well-established ABS protocols, such as gamma-binaural beats (BB) and white noise (WN). We recorded the electroencephalographic brain activity in 28 participants during 4 min of BB, IT d , and WN presentation. Data demonstrated that while both BB and WN enhanced oscillatory power on the EEG gamma band, consistently with the expected brain entrainment effect, IT d yielded greater changes in EEG power (p < 0.001). This was confirmed by time-based analysis, which showed a progressive increase in normalized EEG power within the IT d window compared to BB (p < 0.05). Findings also revealed that IT d elicited acute changes in the alpha band of EEG oscillations, through a progressive decrease in power over time, which was distinctly different from the pattern observed while listening BB and WN. Such dual alpha-gamma effects underline the promising and unique potential of IT d to modulate neural oscillations which selectively differ from BB and WN. This study contributes to the evolution of ABS research, highlighting the promise of IT d for cognitive enhancement and clinical applications. [ABSTRACT FROM AUTHOR]

Transcranial ultrasonic stimulation (TUS) is rapidly emerging as a promising non-invasive neuromodulation technique. TUS is already well-established in animal models, providing foundations to now optimize neuromodulatory efficacy for human applications. Across multiple studies, one promising protocol, pulsed at 1000 Hz, has consistently resulted in motor cortical inhibition in humans (Fomenko et al., 2020). At the same time, a parallel research line has highlighted the potentially confounding influence of peripheral auditory stimulation arising from TUS pulsing at audible frequencies. In this study, we disentangle direct neuromodulatory and indirect auditory contributions to motor inhibitory effects of TUS. To this end, we include tightly matched control conditions across four experiments, one preregistered, conducted independently at three institutions. We employed a combined transcranial ultrasonic and magnetic stimulation paradigm, where TMS-elicited motor-evoked potentials (MEPs) served as an index of corticospinal excitability. First, we replicated motor inhibitory effects of TUS but showed through both tight controls and manipulation of stimulation intensity, duration, and auditory masking conditions that this inhibition was driven by peripheral auditory stimulation, not direct neuromodulation. Furthermore, we consider neuromodulation beyond driving overall excitation/inhibition and show preliminary evidence of how TUS might interact with ongoing neural dynamics instead. Primarily, this study highlights the substantial shortcomings in accounting for the auditory confound in prior TUS-TMS work where only a flip-over sham and no active control was used. The field must critically reevaluate previous findings given the demonstrated impact of peripheral confounds. Furthermore, rigorous experimental design via (in) active control conditions is required to make substantiated claims in future TUS studies. Only when direct effects are disentangled from those driven by peripheral confounds can TUS fully realize its potential for research and clinical applications. [ABSTRACT FROM AUTHOR]

Timing cues such as interaural time differences (ITDs) and temporal pitch are pivotal for sound localization and source segregation, but their perception is degraded in cochlear-implant (CI) listeners as compared to normal-hearing listeners. In multi-electrode stimulation, intra-aural channel interactions between electrodes are assumed to be an important factor limiting access to those cues. The monaural asynchrony of stimulation timing across electrodes is assumed to mediate the amount of these interactions. This study investigated the effect of the monaural temporal electrode asynchrony (mTEA) between two electrodes, applied similarly in both ears, on ITD-based left/right discrimination sensitivity in five CI listeners, using pulse trains with 100 pulses per second and per electrode. Forward-masked spatial tuning curves were measured at both ears to find electrode separations evoking controlled degrees of across-electrode masking. For electrode separations smaller than 3 mm, results showed an effect of mTEA. Patterns were u/v-shaped, consistent with an explanation in terms of the effective pulse rate that appears to be subject to the well-known rate limitation in electric hearing. For separations larger than 7 mm, no mTEA effects were observed. A comparison to monaural rate-pitch discrimination in a separate set of listeners and in a matched setup showed no systematic differences between percepts. Overall, an important role of the mTEA in both binaural and monaural dual-electrode stimulation is consistent with a monaural pulse-rate limitation whose effect is mediated by channel interactions. Future CI stimulation strategies aiming at improved timing-cue encoding should minimize the stimulation delay between nearby electrodes that need to be stimulated successively. [ABSTRACT FROM AUTHOR]

Auditory training can lead to notable enhancements in specific tasks, but whether these improvements generalize to untrained tasks like speech-in-noise (SIN) recognition remains uncertain. This study examined how training conditions affect generalization. Fifty-five young adults were divided into "Trained-in-Quiet" (n = 15), "Trained-in-Noise" (n = 20), and "Control" (n = 20) groups. Participants completed two sessions. The first session involved an assessment of SIN recognition and voice discrimination (VD) with word or sentence stimuli, employing combined fundamental frequency (F0) + formant frequencies voice cues. Subsequently, only the trained groups proceeded to an interleaved training phase, encompassing six VD blocks with sentence stimuli, utilizing either F0-only or formant-only cues. The second session replicated the interleaved training for the trained groups, followed by a second assessment conducted by all three groups, identical to the first session. Results showed significant improvements in the trained task regardless of training conditions. However, VD training with a single cue did not enhance VD with both cues beyond control group improvements, suggesting limited generalization. Notably, the Trained-in-Noise group exhibited the most significant SIN recognition improvements posttraining, implying generalization across tasks that share similar acoustic conditions. Overall, findings suggest training conditions impact generalization by influencing processing levels associated with the trained task. Training in noisy conditions may prompt higher auditory and/or cognitive processing than training in quiet, potentially extending skills to tasks involving challenging listening conditions, such as SIN recognition. These insights hold significant theoretical and clinical implications, potentially advancing the development of effective auditory training protocols. [ABSTRACT FROM AUTHOR]

There is broad consensus that listening effort is an important outcome for measuring hearing performance. However, there remains debate on the best ways to measure listening effort. This study sought to measure neural correlates of listening effort using functional near-infrared spectroscopy (fNIRS) in experienced adult hearing aid users. The study evaluated impacts of amplification and signal-to-noise ratio (SNR) on cerebral blood oxygenation, with the expectation that easier listening conditions would be associated with less oxygenation in the prefrontal cortex. Thirty experienced adult hearing aid users repeated sentence-final words from low-context Revised Speech Perception in Noise Test sentences. Participants repeated words at a hard SNR (individual SNR-50) or easy SNR (individual SNR-50 + 10 dB), while wearing hearing aids fit to prescriptive targets or without wearing hearing aids. In addition to assessing listening accuracy and subjective listening effort, prefrontal blood oxygenation was measured using fNIRS. As expected, easier listening conditions (i.e., easy SNR, with hearing aids) led to better listening accuracy, lower subjective listening effort, and lower oxygenation across the entire prefrontal cortex compared to harder listening conditions. Listening accuracy and subjective listening effort were also significant predictors of oxygenation. [ABSTRACT FROM AUTHOR]

AbstractObjectiveDesignStudy SampleResultsConclusionsTo evaluate the efficacy of sound stimulation for enhancing drug distribution in the cochlea’s perilymph, crucial for treating one of the most inaccessible organs and a major disability factor worldwide.A systematic scoping review following PRISMA guidelines was conducted, analysing studies on cochlear fluid dynamics influenced by sound stimulation. Data were collected from PubMed and Google Scholar using both MeSH and non-MeSH terms, with exclusions for unrelated topics.Thirteen studies met the inclusion criteria, providing insights into the mechanics of cochlear perilymphatic flow and its potential enhancement through sound stimulation.The review highlights two primary mechanisms capable of inducing significant perilymphatic flow from the base towards the apex: complex audible sound stimulation creating a "streaming channel" and low-frequency stimulation at high intensity. Despite the theoretical potential, the clinical applicability of these techniques remains unproven, and the safety of low-frequency, high-intensity stimulation for the cochlea and vestibular system should be demonstrated.Sound stimulation appears to be a viable method for inducing perilymphatic movements, potentially improving drug delivery to remote cochlear regions. Future research should focus on the clinical safety and efficacy of these stimulations to fully utilise this approach in therapeutic applications. [ABSTRACT FROM AUTHOR]

Intensification of swine production can predispose pigs to chronic stress, with adverse effects on the neuroendocrine and immune systems that can lead to health problems, poor welfare, and reduced production performance. Consequently, there is an interest in developing tools to prevent or eliminate chronic stress. Music is widely used as a therapeutic strategy for stress management in humans and may have similar benefits in non-human animals. This study evaluated the effects of a music-based auditory enrichment program in pigs from a multidimensional perspective by assessing psychophysiological responses. Two experimental groups of 20 pigs each were selected for the study: one enriched, exposed to a program of functional veterinary music designed for pigs, and a control group without auditory stimulation. Qualitative behavior assessment (QBA) and skin lesions indicative of agonistic behavior were used to evaluate the psychological determinants underlying the observed behaviors. Physiological assessment included hemograms, with the determination of the neutrophil:lymphocyte ratio and daily measurements of cortisol and salivary alpha-amylase levels. The results demonstrated a positive effect of a music-based auditory program on psychophysiological responses. Therefore, this strategy developed for environmental enrichment may be beneficial in reducing stress and contributing to the welfare and health of pigs under production conditions. [ABSTRACT FROM AUTHOR]

Most voluntary actions have only few goals, which provides considerable freedom in the selection of action parameters. Recent studies showed that task-irrelevant aspects of the task context influence the motor parameters of the actions in a way which seems to reflect the relative importance of these aspects within the underlying action representation. The present study investigated how the intensity of auditory action-effects affected force exertion patterns in a self-paced action production task. Participants applied force impulses with their index finger on a force-sensitive resistor every three seconds. In four separate conditions, force impulses elicited no sound, or elicited tones with 69, 59 or 49 dB intensity. The results showed that participants applied more force when tone intensity was lower, and when tones were absent. These force differences were also present in the first 60 ms following tone onset, implying that these reflected differences in motor planning. The results are compatible with the notion that actions are represented in terms of their sensory effects, which are weighted differently—presumably to maintain an optimal level of overall auditory and tactile stimulation in the present case. These results hint at the potential usefulness of motor parameters as readouts of action intentions. [ABSTRACT FROM AUTHOR]

The study investigated the relationship between the strength of the medial olivocochlear reflex (measured via contralateral inhibition of otoacoustic emissions) and speech perception in noise (obtained from behavioural identification task) through meta-analyses. A systematic review and random-effects meta-analysis of studies investigating the relationship in neurotypical adults was performed. The systematic search (in PubMed, Scopus, Science Direct and Google Scholar databases) revealed 21 eligible studies, which were critically appraised using the NIH tool for Observational Cohort and Cross-Sectional Studies. Meta-analysis was performed on 17 studies (374 participants) with fair to good quality. The results revealed that the medial olivocochlear reflex accounts for less than 1% of the variations in speech perception in noise in neurotypical individuals. Sub-group analyses conducted to address a few methodological differences also revealed no discernible association between the two variables. The results reveal no modulatory effect of the medial olivocochlear reflex assessed using contralateral inhibition of otoacoustic emission on the ability to perceive speech in noise. However, more data utilising alternative measures of medial olivocochlear reflex strength is necessary before drawing any conclusions about the role of the medial olivocochlear bundle in speech perception in noise. [ABSTRACT FROM AUTHOR]

To validate measurement of predicted earmold wideband real-ear-to-coupler difference (wRECD) using an integrated pressure level (IPL) calibrated transducer and the incorporation of an acoustically measured tubing length correction. Unilateral earmold SPL wRECD using varied hearing aid tubing length and the proposed predicted earmold IPL wRECD measurement procedure were completed on all participants and compared. 22 normal hearing adults with normal middle ear status were recruited. There were no clinically significant differences between probe-microphone and predicted earmold IPL wRECD measurements between 500 and 2500 Hz. Above 5000 Hz, the predicted earmold IPL wRECD exceeded earmold SPL wRECDs due to lack of standing wave interference. Test-retest reliability of IPL wRECD measurement exceeded the reliability of earmold SPL wRECD measurement across all assessed frequencies, with the greatest improvements in the high frequencies. The acoustically measured tubing length correction largely accounted for acoustic effects of the participant's earmold. IPL-based measurements provide a promising alternative to probe-microphone earmold wRECD procedures. Predicted earmold IPL wRECD is measured without probe-microphone placement, agrees well with earmold SPL wRECDs and is expected to extend the valid bandwidth of wRECD measurement. [ABSTRACT FROM AUTHOR]

In automated hearing threshold determination procedures, prespecified response- time limits can be applied to evaluate whether a stimulus was truly heard by checking whether the test subject reacts to the onset and the offset of the stimuli within given time intervals. The influence of different response-time limits on the threshold of normal-hearing test subjects was investigated. Two-stage hearing threshold level measurements applying the ISO 8253-1 (2010) bracketing procedure were performed. Pre-tests at 125 Hz and 1000 Hz were carried out with maximum accepted response times of 600 ms, 1000 ms, and 1200 ms. Subsequently, thresholds were measured at the seven octaves between 125 Hz and 8000 Hz with maximum accepted response times of 600 ms and 1000 ms. 15 test subjects in pre-tests, 25 test subjects in the main study. Threshold levels determined with a maximum accepted response time of 1000 ms are 2.6 dB lower than those obtained with a maximum accepted response time of 600 ms (95% CI −1.6 dB to 6.9 dB). The threshold shift was similar at all frequencies. Based on this study, response-time limits after both stimulus onset and offset of at least 1000 ms are recommended. [ABSTRACT FROM AUTHOR]

The present study sought to determine the cochlear frequency regions represented by Auditory Brainstem Responses (ABRs) obtained using the high-pass noise/derived response (HP/DR) technique. Broadband noise sufficient to mask the ABR to 50 dB nHL clicks was HP filtered (96 dB/oct) at 8000, 4000, 2000, 1000 and 500 Hz. Mixed with the clicks and HP noise masker was narrowband noise. Three derived response bands, denoted by the upper and lower high-pass noise frequencies, were obtained: DR4000-2000, DR2000-1000, and DR1000-500. Ten adults with normal hearing, aged 19–27 years (mean age: 22.4 years), were recruited from the community. Frequencies contributing to each DR were determined from the wave V percent amplitude (or latency shift) vs narrowband masker frequency profiles (relative to a no-narrowband-noise condition). Overall, results indicate derived band centre frequencies were closer to the lower HP cut-off frequencies for DR4000-2000 and DR2000-1000, and approximately halfway between the lower HP cut-off and the geometric mean of the two HP frequencies for DR1000-500, with bandwidths of 0.5-1 octave in width. These results confirm the validity of the HP/DR technique for assessing narrow cochlear regions (≤1.0 octave wide), with centre frequencies within ½-octave of the lower HP frequency. [ABSTRACT FROM AUTHOR]

Background: Alzheimer's disease (AD) is a progressive neurodegenerative disorder that severely affects cognitive functions and social behaviors, leading to a significant decline in an individual's quality of life. Auditory processing deficits often precede the clinical symptoms of AD, prompting interest in auditory-based interventions as potential treatments. This scoping review aimed to compile the existing evidence on active and passive auditory-based interventions for individuals with AD and its prodromal stages. Method and results: This scoping review followed Arksey and O'Malley's five-step framework to identify the existing evidence on auditory-based interventions for AD. Four databases (PubMed, Web of Science, CINAHL, and Embase) were used to search for studies on auditory stimulation techniques to treat cognitive decline in AD patients. In total, 14 studies were included in the analysis. Seven studies explored active auditory stimulation techniques, such as the Brain Fitness Program (BrainHQ), aiming to improve cognitive function in individuals with Mild Cognitive Impairment (MCI). The other seven studies focused on passive auditory stimulation, often combined with other sensory stimuli such as light or tactile inputs. Passive stimulation studies have focused mainly on Gamma Entrainment Using Sensory Stimulation (GENUS). The intervention frequency and duration varied across studies, ranging from one session lasting 8 h to a year. Both active and passive auditory stimulation showed potential for enhancing cognitive function in individuals with AD. Conclusion: The literature suggests that auditory stimulation may positively influence cortical wiring and enhance cognitive abilities. Multimodal interventions that combine auditory stimulation with other sensory or behavioural approaches could yield more substantial effects on global cognition. However, the study design, intervention characteristics and outcome measures varied across studies, underscoring the necessity for standardised reporting. Well-designed studies using standard cognitive assessment protocols are recommended. [ABSTRACT FROM AUTHOR]

Summary: Light has many non‐image‐forming functions including modulation of pupil size and stimulation of alertness and cognition. Part of these non‐image‐forming effects may be mediated by the brainstem locus coeruleus. The processing of sensory inputs can be associated with a transient pupil dilation that is likely driven in part by the phasic activity of the locus coeruleus. In the present study, we aimed to characterise the task‐evoked pupil response associated with auditory inputs under different light levels and across two cognitive tasks. We continuously monitored the pupil of 20 young healthy participants (mean [SD] 24.05 [4.0] years; 14 women) whilst they completed an attentional and an emotional auditory task whilst exposed to repeated 30–40‐s blocks of light interleaved with darkness periods. Blocks could either consist of monochromatic orange light (0.16 melanopic equivalent daylight illuminance (EDI) lux) or blue‐enriched white light of three different levels [37, 92, 190 melanopic EDI lux; 6500 K]. For the analysis, 15 and then 14 participants were included in the attentional and emotional tasks, respectively. Generalised linear mixed models showed a significant main effect of light level on the task‐evoked pupil responses triggered by the attentional and emotional tasks (p ≤ 0.0001). The impact of light was different for the target versus non‐target stimulus of the attentional task but was not different for the emotional and neutral stimulus of the emotional task. There is a smaller sustained pupil size during brighter light blocks but, a higher light level triggers a stronger task‐evoked pupil response to auditory stimulation, presumably through the recruitment of the locus coeruleus. [ABSTRACT FROM AUTHOR]

Reacting and responding to an external stimulus is an important component of human performance, and they inform us about a participant's neurophysiological capabilities. Our purpose in this study was to determine whether reaction times (REACT), response times (RT), and countermovement jump (CMJ) performance differ when responding to an auditory (AUD) versus visual (VIS) stimulus. Participants were 17 college-aged volunteers (6 females and 11 males; M age = 23.0, SD = 3.4 years; M height = 174.57, SD = 10.37 cm; M body mass = 73.37, SD = 13.48 kg). Participants performed CMJs on force plates immediately upon receiving an AUD or a VIS stimulus. The AUD stimulus was a beep noise, while the VIS stimulus was a light on a screen in front of the participants. We determined REACT for the tibialis anterior (TA), medial gastrocnemius (GM), vastus lateralis (VL), and biceps femoris (BF) muscles to be the amount of time between stimulus onset and the initiation of the muscle's electromyographic (EMG) signal. We determined RT to be the amount of time between stimulus onset and the beginning of the participant's force production. We assessed CMJ performance via ground reaction forces during the unweighting, braking, and propulsive phases of the jump. We quantified EMG amplitude and frequency during each CMJ phase. We found RT to be faster to the AUD versus the VIS stimulus (p =.007). VL and BF muscles had faster REACT than TA and GM muscles (p ≤.007). The AUD stimulus was associated with faster CMJ unweighting phase metrics (p ≤.005). Thus, individuals may react and respond faster to an AUD versus VIS stimulus, with limited improvements in their subsequent physical performance. [ABSTRACT FROM AUTHOR]

Objectives: The exclusive endoscopic transcanal transpromontorial approach (EETTA) has recently been developed for the removal of small‐sized acoustic neuromas in the labyrinth (intralabyrinthine schwannoma [ILS]) or internal auditory canal (IAC). Although small tumors that meet the indications for EETTA are also good candidates for cochlear implantation (CI), there are few reports on CI after schwannoma removal using EETTA. Here we present an outcome of patients who underwent simultaneous EETTA and CI. Methods: Five patients (two with IAC fundus tumors and three with ILS) who underwent simultaneous EETTA and CI between 2020 and 2022 were retrospectively enrolled. Their medical charts and test results were reviewed. Results: After at least 12 months of follow‐up, there were no severe surgical complications such as meningitis, infection, or skin necrosis. Four of the five patients responded to auditory stimulation. Three out of four auditory‐responsive patients scored >80% on sentence recognition. Conclusion: Simultaneous EETTA and CI are feasible for the treatment of ILS and IAC fundus tumors. Preservation of the cochlear nerve and modiolus is important for favorable CI outcomes. Therefore, ILS and IAC fundus tumors in patients with nonserviceable hearing should be surgically removed as early as possible to enable proper hearing rehabilitation with CI. Level of Evidence: Level 4. [ABSTRACT FROM AUTHOR]

Auditory stimulation may be beneficial or detrimental to human cognitive and memory processing. Numerous studies have been conducted to investigate the influence of various sounds on human performance. The current research discovers the impact of auditory white noise on the memory performance of 60 college students using different difficulty levels in visual object-number pair assessment. Memory perfomance is accessed based on the assessment recall scores and brain activities. An electroencephalography (EEG) device measures and records the brain's electrical activity during the experimental session. Nine EEG channel locations are selected for brain activities analysis. The raw EEG dataset is processed using wavelet methods of stationary wavelet transform (SWT) and discrete wavelet transfrom (DWT) using the Daubechies (db) function to eliminate the artifact components and extract the required EEG features. The result indicated that the college student remembered the object-number pair assessment better under auditory white noise rather than no audio condition. This contributed from the activation of alpha, theta, gamma, and beta activities that increased the subject's attention, alertness, and sensory processing during memorizing. Therefore, it is suggested that the auditory white noise should be listened to during remembering and learning visual items, which can boost memory performance. [ABSTRACT FROM AUTHOR]