Trends in Hearing

Everyday listening relies on the auditory systems ability to automatically monitor the background soundscape and detect new or changing sources. Although change detection is a fundamental aspect of situational awareness, little is known about how hearing impairment affects this ability. This study examined how sensorineural hearing loss influences spatial auditory change detection. Older hearing-impaired listeners (N = 30) completed a spatial change detection task requiring them to identify the appearance of a new sound source within a complex spatialised acoustic scene. Hearing loss was characterised by three factors that were measured with standard clinical tests: audiometric hearing thresholds, sensitivity to small level changes, and sensitivity to spectrotemporal modulation. Simple and mixed-effects linear models were used to test how these factors predicted reaction time, hit rate, and false alarm rate. Listeners with poorer spectrotemporal sensitivity, higher audiometric hearing thresholds, and older age showed slower and less accurate detection, whereas sensitivity to small changes in level did not predict outcomes. Detection also varied with spatial location, where appearing sources from behind were detected more slowly and less accurately than those from the front or sides. Numerical analysis using head-related transfer functions confirmed that these rear-field effects were unlikely to be explained by overall or frequency-specific acoustic level differences. These findings reveal that hearing loss, age, and spatial factors jointly shape listeners ability to monitor dynamic auditory scenes. Additionally, testing spectrotemporal sensitivity offers a promising clinical measure of non-speech auditory processing with relevance for hearing-aid fitting and situational awareness.

The auditory system is unique among sensory systems in its ability to phase lock to and precisely follow very fast cycle-by-cycle fluctuations in the phase of sound-driven cochlear vibrations. Yet, the perceptual role of this temporal fine structure (TFS) code is debated. This fundamental gap is attributable to our inability to experimentally manipulate TFS cues without altering other perceptually relevant cues. Here, we circumnavigated this limitation by leveraging individual differences across 200 participants to systematically compare variations in TFS sensitivity to performance in a range of speech perception tasks. TFS sensitivity was assessed through detection of interaural time/phase differences, while speech perception was evaluated by word identification under noise interference. Results suggest that greater TFS sensitivity is not associated with greater masking release from fundamental-frequency or spatial cues, but appears to contribute to resilience against the effects of reverberation. We also found that greater TFS sensitivity is associated with faster response times, indicating reduced listening effort. These findings highlight the perceptual significance of TFS coding for everyday hearing. Significance StatementNeural phase-locking to fast temporal fluctuations in sounds-temporal fine structure (TFS) in particular- is a unique mechanism by which acoustic information is encoded by the auditory system. However, despite decades of intensive research, the perceptual relevance of this metabolically expensive mechanism, especially in challenging listening settings, is debated. Here, we leveraged an individual-difference approach to circumnavigate the limitations plaguing conventional approaches and found that robust TFS sensitivity is associated with greater resilience against the effects of reverberation and is associated with reduced listening effort for speech understanding in noise.

ObjectiveLipreading, which plays a major role in the communication of the hearing impaired, lacked a French standardised tool. Our aim was to create and validate an audio-visual (AV) version of the French Matrix Sentence Test (FrMST). DesignVideo recordings were created by dubbing the existing audio files. SampleThirty-five young, normal-hearing participants were tested in auditory and visual modalities alone (Ao, Vo) and in AV conditions, in quiet, noise, and open and closed-set response formats. ResultsLipreading ability (Vo) varied from 1% to 77%-word comprehension. The absolute AV benefit was 9.25[L]dB SPL in quiet and 4.6[L]dB SNR in noise. The response format did not influence the results in the AV noise condition, except during the training phase. Lipreading ability and AV benefit were significantly correlated. ConclusionsThe French video material achieved similar AV benefits as those described in the literature for AV MST in other languages. For clinical purposes, we suggest targeting SRT80 to avoid ceiling effects, and performing two training lists in the AV condition in noise, followed by one AV list in noise, one Ao list in noise and one Vo list, in a randomised order, in open or close set-format.

The brain computes sound location from auditory spatial cues. Humans and barn owls can localize sounds with high accuracy, yet they rely on fundamentally different cue configurations shaped by their ear anatomy and neural circuitry. In humans, symmetrical ears provide interaural time and level differences for horizontal localization, while vertical localization depends primarily on high-frequency, monaural spectral cues generated by the pinnae. Barn owls, by contrast, possess asymmetrical ears and use binaural cues to localize sounds in both azimuth and elevation. Because auditory pathways are assumed to be tuned to the statistics of species-specific cues, it remains unclear whether humans can localize sounds using barn-owl-like spatial information. We addressed this by fitting human listeners with asymmetric ear molds that disrupted normal spectral cues and introduced elevation-dependent interaural level differences, while preserving interaural time differences. Participants wore the molds during daily life and were tested on sound localization using broadband, high-pass, and low-pass noise. Acute exposure to the molds severely degraded elevation localization, while horizontal localization remained largely unaffected. With prolonged exposure, elevation localization improved, but adaptation was limited. Crucially, improvement was strongest for broadband sounds. Because broadband sounds uniquely provide access to both low-frequency interaural time differences and high-frequency interaural level differences, this pattern indicates that listeners learned to use binaural cues to infer sound elevation. These findings demonstrate that the human auditory system can partially adapt to extreme barn-owl-like outer-ear acoustics. Binaural cues can be repurposed to support elevation localization, with effective learning requiring access to complementary spatial cues. Conceptual takeawayGive humans asymmetric barn-owl ears and they can learn to use them - but only partially. The auditory brain is flexible enough to reinterpret new ear shapes, yet is strongly constrained in how far it can relearn a fundamentally different auditory space.

Pure tone audiometry (PTA) remains the clinical standard for evaluating hearing ability, yet individuals with similar audiometric profiles often exhibit substantial variability in their capacity to understand speech in everyday listening environments. Growing evidence suggests this variance is related to contributions from cognitive ability and auditory processing that standard threshold measures do not capture. To investigate how PTA, cognitive factors, and demographics such as age jointly predict real-world speech perception, 116 veteran adults 20-70 years old spanning a range of normal to moderate sensorineural hearing losses completed a spatial auditory attention task. Target color words were embedded within naturalistic short-story narratives presented under two conditions: a mono-talker speech-in-quiet (SIQ) condition and a dual-talker speech-in-noise (SIN) condition with a spatially separated competing narrative. Behavioral performance was quantified via color word hit accuracy, reaction time, and comprehension question accuracy. Participants also completed pure tone audiometry, the Montreal Cognitive Assessment (MoCA), and the Speech, Spatial and Qualities of Hearing Scale (SSQ12). Mixed-effects regression models were used to evaluate the contributions of PTA, age, cognitive ability, and self-reported hearing difficulty (SSQ12) to task performance across conditions. Results demonstrate a complex interplay between age, PTA, MoCA, and/or listening condition (SIQ vs. SIN) in predicting identification accuracy, reaction time, and comprehension. Age and condition significantly predicted hit accuracy and reaction time, with older participants showing improved accuracy in quiet but declining accuracy and slower responses in noise. PTA did not emerge as a significant main effect predictor but interacted with cognitive ability and condition to modulate performance, in some cases exhibiting a paradoxical inverse relationship with accuracy dependent on MoCA score. MoCA scores significantly predicted comprehension across conditions, and SIN hit accuracy was positively correlated with SSQ12 scores, validating the task against participants real-world listening experiences. These findings highlight the importance of incorporating cognitive screening and ecologically valid speech perception tasks into audiological assessment to better identify individuals at risk for functional hearing impairment in complex listening environments.

Investigations of the role of audiovisual integration in speech-in-noise perception have largely focused on the benefits provided by lipreading cues. Nonetheless, audiovisual temporal coherence can offer a complementary advantage in auditory selective attention tasks. We developed an audiovisual speech-in-noise test to assess the benefit of visually conveyed phonetic information and visual contributions to auditory streaming. The test was a video version of the Childrens Coordinate Response Measure with a noun as the second keyword (vCCRMn). The vCCRMn allowed us to measure speech reception thresholds in the presence of two competing talkers under three visual conditions: a full naturalistic video (AV), a video which was interrupted during the target word presentation (Inter), thus, providing no lipreading cues, and a static image of a talker with audio only (A). In each case, the video/image could display either the target talker, or one of the two competing maskers. We assessed speech reception thresholds in each visual condition in 37 young ([≤] 35 years old) normal-hearing participants. Lipreading ability was independently assessed with the Test of Adult Speechreading (TAS). Results showed that both target-coherent AV and Inter visual conditions offer participants a listening benefit over the static image audio-only condition, with the full AV target-coherent condition providing the most benefit. Lipreading ability correlated with the audiovisual benefit shown in the full AV target-coherent condition, but not the benefit in the Inter target-coherent condition. Together our results are consistent with visual information providing independent benefits to listening, through lip reading and enhanced auditory streaming.

Auditory experience plays a critical role in hearing development. Developmental auditory deprivation due to otitis media, a common childhood disease, produces long-standing changes in the central auditory nervous system, even after the middle ear pathology is resolved. The effects of sound deprivation due to otitis media have been mostly studied in the ascending neural system but remain to be examined in the descending pathway that runs from the auditory cortex to the cochlea via the brainstem. Alterations in the efferent neural system could be important because the descending olivocochlear pathway influences the neural representation of transient sounds in noise in the afferent auditory system and is thought to be involved in auditory relearning following injury. The main objectives of the present study were to (1) investigate whether degraded auditory input due to otitis media during childhood is associated with weakened medial olivocochlear efferent neural responses, even after the resolution of the middle ear pathology, and (2) to examine the involvement of the efferent neural feedback in perceptual masking deficits associated with auditory deprivation due to otitis media. We measured contralateral inhibition of otoacoustic emissions--a biomarker for medial efferent activity--and speech-in-noise recognition in children with a medical history of otitis media (N=76) and age-matched controls (N=99). All children had normal auditory function at the time of experimentation. We found that the inhibitory strength of the medial olivocochlear efferents is weaker in children with a documented history of otitis media relative to controls. In addition, children with otitis media history required a more advantageous signal-to-noise ratio than controls to achieve the same criterion performance level. Importantly, the deficits in perceptual masking were related to efferent inhibition, and these effects could not be attributed to the middle ear or cochlear mechanics. These findings raise the possibility that perceptual masking deficits--a hallmark of impaired (central) auditory processing--resulting from otitis media can arise from the altered brainstem efferent feedback. To date, it was known that degraded auditory experience reorganizes the ascending neural pathways; here, we show that the lack of optimal auditory input to the afferent system during development could have a long-standing impact on the functioning of the descending neural pathways.

In conventional hearing-aid personalisation, clinicians cannot hear what their patients hear, and patients cannot often reliably detect or describe what they hear. Self-adjustment avoids this issue but requires user controls that adjust hearing-aid signal processing parameters to be effective, efficient and easy. In this study, we explored (a) the roles of interface complexity and stimulus type in the self-adjustment of hearing-aid gain, and (b) how well individuals can adjust one sound to match another to assess the same interfaces and stimuli. Adult hearing-aid users with mild to moderate symmetrical sensorineural hearing loss repeatedly adjusted the gain (a) to their preference from individual prescription (n = 41) and (b) to match their previous preferences from a random starting point (n = 32) using three interfaces representing different bass/mid/treble configurations and three stimuli (music, speech and speech-in-noise). The large interindividual variability in self-adjusted gains clustered into three patterns of deviation from initial prescription: increased relative bass, overall gain reduction, and close to initial prescription. There were no substantial effects of interface nor stimulus on self-adjustment reliability (median {sigma} = 2.8 dB), whereas absolute sound-matching error increased with increasing interface complexity and centre frequency. Neither individual matching accuracy nor questionnaire responses predicted either self-adjusted gains or reliability. Overall, these results show that many - but not all - hearing-aid users can adjust gains with reasonable reliability, and while it can be difficult to predict the behaviour from the individual, the individual applies a similar self-adjustment behaviour across different interfaces and stimuli.

In noisy or cluttered environments, sensory cortical mechanisms help combine auditory or visual features into perceived objects. Knowing that individuals vary greatly in their ability to suppress unwanted sensory information, and knowing that the sizes of auditory and visual cortical regions are correlated, we wondered whether there might be a corresponding relation between an individuals ability to suppress auditory vs. visual interference. In auditory masking, background sound makes spoken words unrecognizable. When masking arises due to interference at central auditory processing stages, beyond the cochlea, it is called informational masking (IM). A strikingly similar phenomenon in vision, called visual crowding, occurs when nearby clutter makes a target object unrecognizable, despite being resolved at the retina. We here compare susceptibilities to auditory IM and visual crowding in the same participants. Surprisingly, across participants, we find a negative correlation (R = -0.7) between IM susceptibility and crowding susceptibility: Participants who have low susceptibility to IM tend to have high susceptibility to crowding, and vice versa. This reveals a mid-level trade-off between auditory and visual processing.

Our perceptual system bins elements of the speech signal into categories to make speech perception manageable. Here, we aimed to test whether hearing speech in categories (as opposed to a continuous/gradient fashion) affords yet another benefit to speech recognition: parsing noisy speech at the "cocktail party." We measured speech recognition in a simulated 3D cocktail party environment. We manipulated task difficulty by varying the number of additional maskers presented at other spatial locations in the horizontal soundfield (1-4 talkers) and via forward vs. time-reversed maskers, promoting more and less informational masking (IM), respectively. In separate tasks, we measured isolated phoneme categorization using two-alternative forced choice (2AFC) and visual analog scaling (VAS) tasks designed to promote more/less categorical hearing and thus test putative links between categorization and real-world speech-in-noise skills. We first show that listeners can only monitor up to [~]3 talkers despite up to 5 in the soundscape and streaming is not related to extended high-frequency hearing thresholds (though QuickSIN scores are). We then confirm speech streaming accuracy and speed decline with additional competing talkers and amidst forward compared to reverse maskers with added IM. Dividing listeners into "discrete" vs. "continuous" categorizers based on their VAS labeling (i.e., whether responses were binary or continuous judgments), we then show the degree of IM experienced at the cocktail party is predicted by their degree of categoricity in phoneme labeling; more discrete listeners are less susceptible to IM than their gradient responding peers. Our results establish a link between speech categorization skills and cocktail party processing, with a categorical (rather than gradient) listening strategy benefiting degraded speech perception. These findings imply figure-ground deficits common in many disorders might arise through a surprisingly simple mechanism: a failure to properly bin sounds into categories.

Humans localise sounds in the horizontal plane by processing level and timing differences between the ears. This neurocomputational process is continuously and adaptively calibrated using visual input, as seen in the ventriloquism after effect: a shift in sound perception toward a previously seen light. It is unknown from where in the brain this aftereffect originates; adaptation could occur at an early level in the auditory system where neurons are narrowly tuned to frequency, at a later level in the auditory system where localisation cues are extracted, or outside the auditory system at a higher-level spatial map. To investigate this, we examined how the ventriloquism aftereffect generalises across sound frequencies. Participants localised seven narrowband sounds (0.5-8 kHz), targeting different localisation cues. We found that sound localisation accuracy in darkness varied slightly with frequency. When sounds were paired with a visual stimulus that was offset by 10 deg, participants exhibited a pronounced bias toward the light of about [~]63%, corresponding to the well-known ventriloquism effect. The bias was stronger for narrowband compared to broadband sounds. After exposure to a block of these audiovisual stimuli, a ventriloquism aftereffect in the form of a spatial bias of [~]12% was observed across all tested frequencies, largely independent of the frequency of the exposure sound. Together with earlier reports of both frequency-specific and frequency-general recalibration, our results indicate that under conditions of a fixed and consistent audiovisual spatial offset, the ventriloquism aftereffect generalises across sound frequencies, consistent with adaptation at a frequency-independent multisensory spatial stage.

The sounds we experience in our everyday communication can vary greatly in terms of level and background noise depending on the environment. Paradoxically, increasing the sound intensity may lead to worsened speech understanding, especially in noise. This is known as the "Rollover" phenomenon. There have been limited studies on rollover and how it is experienced differentially across aging groups, for those with and without hearing loss, as well as cochlear implant (CI) users. There is also mounting evidence that listening effort plays an important role in challenging listening conditions and can be directly quantified with objective measures such as pupil dilation. We found that listening effort was modulated by sound level and that rollover occurred primarily in the presence of background noise. The effect on listening effort was exacerbated by age and hearing loss in acoustic listeners, with greatest effect in older listeners with hearing loss, while there was no effect in CI users. The age- and hearing-dependent effects of rollover highlight the potential negative impact of amplification to high sound levels and therefore has implications for effective treatment of age-related hearing loss.

IntroductionThis study examined the impact of instructions on the prioritization strategy employed by individuals during a listening effort dual-task paradigm. MethodsThe dual-task paradigm consisted of a primary speech understanding task in different listening conditions and a secondary visual memory task, both performed separately (baseline) and simultaneously (dual-task). Twenty-three normal-hearing participants (mean age: 36.8 years; 14 females) were directed to prioritize the primary speech understanding task in the dual-task condition, whereas another twenty-three (matched for age, gender, and education level) received no specific instructions regarding task priority. Both groups performed the dual-task paradigm twice (mean interval: 14.8 days). Patterns of dual-task interference were assessed by plotting the dual-task effect of the primary and secondary task against each other. Fishers exact tests were used to assess whether there was an association between interference patterns and group (non-prioritizing and prioritizing) across all listening conditions and test sessions. ResultsNo statistically significant association was found between the pattern of dual-task interference and the group to which the participants belong for any of the listening conditions and test sessions. Descriptive analysis revealed no consistent strategy use within individuals across listening conditions and test sessions, suggesting a lack of a uniform approach regardless of the given instructions. ConclusionProviding prioritization instructions was insufficient to ensure that an individual will mainly focus on the primary task and consistently adhere to this strategy across listening conditions and test sessions. These results raised reservations about the current usage of dual-task paradigms for listening effort.

Selective auditory attention decoding (AAD) enables tracking which of multiple concurrent speakers a listener attends to and is a key building block for neuro-steered hearing devices. While AAD integrated in a closed-loop system with real-time neurofeedback (NFB) is hypothesized to improve decoding through neural adaptation and error-correction behaviour, the short-term behavioral and algorithmic impact of such a bilateral human-machine interaction remains poorly understood. Here we evaluated the effects of NFB on AAD accuracy and user experience in a single-session AAD paradigm with online NFB involving nineteen participants. They performed a selective listening task with enforced attention switches across four conditions: open-loop (OL), closed-loop with auditory gain feedback (CLA), closed-loop with visual feedback (CLV), and a condition with pseudo-auditory gain control (psCLA) decoupled from the participants individual neural activity. AAD was performed online using both subject-specific and subject-independent linear decoders on 5 s sliding windows, followed by Hidden Markov Model post-processing. Online analysis showed comparable decoding performance across all conditions. However, offline posthoc analysis using subject-independent decoders revealed that AAD accuracy in the CLA condition was significantly lower than in the OL baseline. Subjectively, participants reported that CLA was significantly more distracting and required higher switching effort. Crucially, a causal analysis of the psCLA condition found no robust evidence that higher audio gains inherently improve decoding accuracy. Our results demonstrate that within a single-session paradigm with rapidly varying feedback cues, auditory neurofeedback may degrade AAD performance by increasing cognitive load and distraction. These findings suggest that suboptimal feedback can impede rather than facilitate learning. We conclude that more accurate and stable decoders and longitudinal, multi-session training protocols are likely essential prerequisites for achieving beneficial neurofeedback effects in closed-loop auditory attention systems.

ObjectivesCochlear implant (CI) users exhibit a large variance in understanding speech in noise (SiN). Past works in CI users found that spectral and temporal resolutions correlate with the SiN ability, but a large portion of variance has been remaining unexplained. Our groups recent work on normal-hearing listeners showed that the ability of grouping temporally coherent tones in a complex auditory scene predicts SiN ability, highlighting a central mechanism of auditory scene analysis that contributes to SiN. The current study examined whether the auditory grouping ability contributes to SiN understanding in CI users as well. Design47 post-lingually deafened CI users performed multiple tasks including sentence-in-noise understanding, spectral ripple discrimination, temporal modulation detection, and stochastic figure-ground task in which listeners detect temporally coherent tone pips in the cloud of many tone pips that rise at random times at random frequencies. Accuracies from the latter three tasks were used as predictor variables while the sentence-in-noise performance was used as the dependent variable in a multiple linear regression analysis. ResultsNo co-linearity was found between any predictor variables. All the three predictors exhibited significant contribution in the multiple linear regression model, indicating that the ability to detect temporal coherence in a complex auditory scene explains a further amount of variance in CI users SiN performance that was not explained by spectral and temporal resolution. ConclusionsThis result indicates that the across-frequency comparison builds an important auditory cognitive mechanism in CI users SiN understanding. Clinically, this result proposes a novel paradigm to reveal a source of SiN difficulty in CI users and a potential rehabilitative strategy.

Many sounds contain spectral modulations at multiple scales, but much is still unknown about how such spectral features are represented in the auditory system. One behavioral task that provides insight into this question is profile analysis. In a typical profile-analysis task, listeners are asked to discriminate between a complex tone with equal-amplitude components and a complex tone with a single incremented component. Because listeners can perform profile analysis even when the overall sound level of the stimuli is randomized from interval to interval, this task is thought to be a useful index of relative processing of spectral shape, rather than just sensitivity to absolute level changes. Here, we measured profile analysis across the frequency range in a group of listeners that varied widely in their hearing status. We then modeled the resulting behavioral data by decoding responses to the stimuli from computational models of the auditory nerve and inferior colliculus. We found that both hearing loss at the target frequency and increases in the target frequency were associated with poorer profile-analysis thresholds, and that these results could both be explained as the result of corresponding changes in sensitivity of temporal modulation-sensitive cells at the level of the inferior colliculus. These results suggest that key features of profile-analysis may reflect the limits of central neural tuning to temporal modulations.

Experiments on human auditory perception have shown that interaural time difference (ITD) is sufficient to generate spatial percepts, even though stimuli containing only the ITD cue are perceived as being emitted from inside the head instead of from external locations at specific azimuths. These experiments are thus interpreted as "lateralization" instead of "localization" tasks. In fact, lateralized spatial perception has been quantified using tasks in which participants have to report their estimates by selecting a putative location inside the head, or matching the perceived position to sounds with a given interaural level difference. Therefore, these estimates are made with respect to internal frames of reference, but it is unclear whether these percepts have any significance for the more ecological problem of locating an external sound source. In order to investigate the link between internalized spatial percepts and sound localization, we designed a new task in which subjects are instructed to report externalized azimuthal location for sounds containing only ITD cues. Despite the mismatch between an internalized percept having to be reported as emanating from an external location, subjects were able to estimate azimuths consistently. Furthermore, normalized estimates were indistinguishable from those obtained using traditional lateralization tasks. Our results revealed a direct relationship between perceived azimuths and ITD, which deviates from that obtained from acoustical analysis of binaural recordings, revealing estimation biases. Intriguingly, these results indicate that externalized percepts are not required for the generation of azimuthal percepts.

PurposeSpeech perception requires that listeners classify sensory information into smaller groupings while also coping with noise that often corrupts the speech signal. The strength of categorization and speech-in-noise (SIN) abilities show stark individual differences. Some listeners perceive speech sounds in a gradient fashion, while others categorize in a discrete/binary manner, favoring fine acoustic details vs. a more abstract phonetic code, respectively. Prior work suggests SIN processing is (i) related to more gradient phonetic perception and (ii) varies with musical training. MethodTo further probe relations between perceptual gradiency and noise-degraded listening, we measured phoneme categorization, SIN recognition (QuickSIN), and sentence recognition in listeners with varying musical backgrounds. Categorization was measured for vowels and stops using standard labeling tasks. Speech recognition and discrimination were assessed using "elliptical speech" sentences that use featural substitutions which renders them meaningless under clean conditions but surprisingly improves their recognition under noise degradation. We hypothesized listeners who use broader perceptual equivalency classes in hearing elliptical speech would show better SIN perception, indicative of a more gradient listening strategy. ResultsListeners perceived elliptical sentences as sounding different than their intact counterparts in the clear but as the same under noise degradation. But this elliptical benefit varied with music background. Nonmusicians showed larger susceptibility and noise-related benefit of ellipses than musicians, consistent with the notion they used broader phonetic categories (i.e., more gradient listening). Elliptical speech perception was also associated with QuickSIN performance in both groups but in opposite ways. ConclusionsUse of broader categories was related to better SIN processing in nonmusicians but poorer SIN processing in musicians. Findings suggest listeners can use broader perceptual equivalence classes to deal with degraded listening situations but this depends critically on their auditory demographics. Nonmusicians might use broader phonetic categories to aid SIN perception while musicians might use narrower categories or otherwise similar speech contexts.

ObjectivesThe auditory brainstem response (ABR) is an essential tool in screening for and diagnosing infant hearing loss, and its results drive decisions regarding interventions and hearing habilitation with impacts extending far into a childs future. Despite the traditional ABR exams usefulness, there is an identified need to develop faster, more informative exams. The parallel ABR (pABR) measures responses to all frequencies of interest in both ears all at once, rather than the traditional series of single-frequency measurements in one ear at a time, greatly speeding the diagnostic exam. The pABR has been shown to be effective at quickly measuring frequency-specific responses in adults with normal hearing, but it has not yet been tested in people with hearing loss. The goal of this study was to determine the accuracy and speed of the pABR for estimating hearing thresholds in a clinic-like setting. DesignSeventy adults with widely varying sensorineural hearing loss configurations were recruited to participate in this study. We measured thresholds at octave frequencies in two ways: the behavioral audiogram, serving as the ground truth, and using the pABR with a custom-designed interactive user interface. Accuracy was determined through threshold correlation coefficients as well as absolute error in decibels. Acquisition time was assessed as the time from measurement start to determination of the final threshold. To determine the pABRs speed advantages, a subset of participants was invited back and their thresholds estimated a third time, using a commercially available clinical system to serially measure ABR waveforms. Speedup was assessed in terms of the raw difference in acquisition time in minutes and as the ratio between measurement times made with the two ABR paradigms. ResultsThresholds estimated with pABR highly correlated with the behavioral audiogram ground truth. The correlation was 0.90 (0.88-0.92, 95% confidence interval) across all ears and frequencies. 79% of pABR thresholds were within one 10-dB step-size of the behavioral threshold. The pABR was faster in all ten participants where traditional serial ABR was also recorded, with a mean recording time of 28 minutes to estimate ten pABR thresholds (500-8000 Hz in each ear) versus 70 minutes to estimate eight serial thresholds (500-4000 Hz in each ear), or a mean reduction of 42 minutes. The median speedup ratio was 2.5x. ConclusionsThe pABR provides accurate threshold estimates with greatly reduced measurement time compared to traditional methods. Given these results and other advantages related to its design, the pABR holds promise as a clinical tool that can be deployed to commercial systems in the near future.

ObjectivePersons with hearing aids or cochlear implants often have difficulty understanding speech well despite amplification, especially in noisy environments. Auditory training can help their brain refine their listening skills. The current study aimed to determine the efficacy of the ALICE program, a self-guided home-based health care program including monitoring, training and counselling. MethodA multicentric study was carried out, including hearing aid centers and a cochlear implant center in Flanders (Belgium). Participants were assigned randomly to an intervention or control group. Participants in the intervention group received a tailored flow of exercises that could be streamed to the device or presented in sound field. All participants were tested before and after 8 weeks using sentences in noise and different self-reports. ResultsParticipants in the intervention group were compliant during the 8-week training period. Significant on-task improvements were observed, as well as improved speech in noise understanding for the intervention group only. The self-report data did not reveal changes following the intervention. ConclusionsOur clinical trial shows that the self-guided ALICE training program is effective at improving the auditory systems ability to parse untrained speech in noise. This enhancement in speech in noise performance is specific to the training group, as the control group did not improve. The results of the clinical trials imply that ALICE can be used as a scalable, accessible, and safe hearing care intervention.