Speech intelligibility performance while wearing three different hearing protective devices

Spatial perception with over-the-counter hearing aids

While hearing aids are critical for providing audibility and supporting speech intelligibility, they can have negative effects on spatial perception. Currently, the range of available styles of hearing aids is rapidly expanding with the introduction of over-the-counter devices (OTCs), but little is known about their effects on spatial perception. Importantly, these devices are aimed at listeners with relatively mild hearing losses, who may be especially sensitive to spatial distortions. Our broad goal is to comprehensively characterize spatial perception with different OTCs, considering azimuth identification, front-back discrimination, and sound externalization. In an initial study, twelve adult listeners with normal hearing were bilaterally fitted with OTCs representing different form factors: behind-the-ear (BTE; Lexie B2 Plus with open and closed domes), completely-in-canal (CIC; Eargo SE), and earbuds (Apple Pro 2). Each listener completed the different spatial tasks while wearing each set of devices, with unaided performance as a reference. While the mean results revealed disruptive effects of each OTC for all tasks, the size of the effect depended strongly on the device and on the individual listener. A follow-up study is expanding the set of OTCs, including listeners with mild-to-moderate hearing loss, and supplementing the behavioral results with acoustical analyses of ear-canal signals.

[Effects of bone conduction device on speech recognition in noise and listening effort in patients with single-sided deafness].

Chirped Speech (Cheech) Enables Rapid Assessment of Multi-Level Auditory Evoked Potentials During Speech-in-Noise Recognition

Difficulties understanding speech in noise remain a common complaint even among listeners with normal hearing sensitivity, highlighting the need for objective, more effective measures of real-world listening. The goal of this study was to validate the use of a novel, chirped-speech (Cheech) stimulus—continuous, naturally-spoken speech fused with chirps designed to elicit robust auditory evoked potentials—to characterize relationships between speech recognition, listening effort, and auditory neural encoding. Twenty-five normal-hearing adults completed a sentence-recognition task using both original (unmodified) and Cheech-modified AzBio sentence lists in quiet, +3 dB, and −3 dB signal-to-noise ratio (SNR) conditions while neural responses from the brainstem through cortex were recorded simultaneously. Speech recognition remained near ceiling in quiet but declined with decreasing SNR for both original and Cheech stimuli. Compared with clean speech, Cheech-modified speech showed slightly poorer recognition performance as SNR decreased and somewhat higher perceived effort overall. Yet, Cheech was highly effective at evoking auditory responses from the brainstem (auditory brainstem response, ABR) through the cortex (including middle- and late-latency responses, MLR and LLR) even with <5 minutes listening time per condition. Neural responses showed reduced amplitudes and prolonged latencies as SNR decreased. In general, ABR latencies and wave I amplitudes were associated with speech-in-noise recognition performance, whereas cortical responses (MLR Na, Nb, and LLR P1) were associated with subjective workload. These findings show that Cheech-modified speech preserves intelligibility while yielding robust, multilevel neural recordings during sentence perception, offering a promising approach to examine hierarchical auditory processing under ecologically relevant speech-in-noise conditions.

Broadband Noise Acoustic Stapedial Reflex Thresholds as a Marker of Cochlear and Neural Integrity in Individuals with Normal Audiograms

Background/Objectives: Some individuals present with difficulty understanding speech in noise, tinnitus, or both, despite normal conventional audiometric hearing thresholds. This study evaluated whether acoustic stapedial reflex thresholds (ASRTs) could serve as a clinically useful indicator of auditory complaints not captured by conventional audiometry. Methods: ASRTs for pure tones and broadband noise (BBN) were measured in 146 ears (73 participants) from controls, music students, and symptomatic participants. Bayesian random-intercept linear regression models were used to compare ASRTs among groups, adjusting for age and sex. ASRT difference scores were also used for ROC analysis and to estimate the difference between pure-tone and BBN thresholds (“BBN advantage”). Results: Symptomatic ears showed higher ASRTs than control ears with BBN stimuli, after adjustment for age and sex. Symptomatic ears had a lower AvgDiff posterior mean (reduced BBN advantage) than control ears. ASRTs for music students were directionally consistent with an intermediate pattern, but with wider credible intervals and greater uncertainty. Exploratory ROC analysis showed moderate separation between symptomatic and non-symptomatic ears with AvgDiff; however, symptom status was not independently validated against any diagnostic reference standard. Conclusions: The study suggests that a reduced BBN advantage may be associated with auditory complaints in individuals with normal hearing at conventional audiometric frequencies. However, these findings should be interpreted with caution and not used for specific diagnostic purposes, as the symptomatic group was substantially older and symptom status was not independently validated against any diagnostic reference standard.

Relating Sound Externalization, Own-Voice Perception, and Occlusion in Adults With Hearing Aids.

OBJECTIVES A recent study found that hearing aids fitted with highly occluding domes had an impact on the perception of externally presented speech, producing sound images that were perceived as too close or even inside the head. The present study examined whether this phenomenon is related to the well-known occlusion effect, which describes changes in ear canal levels and perceived own-voice quality during speaking. DESIGN Participants were 10 young adults with normal hearing and 10 young adults with sensorineural hearing loss. All participants were fitted with both closed- and open-fit hearing aids, and hearing aid users were also tested with their own devices. Externalization was measured using a numerical scale from 0 (inside the head) to 10 (at the loudspeaker). Participants also rated the naturalness of their own voice while speaking using a subjective scale from 1 (most unnatural) to 10 (most natural). Occlusion was also measured objectively for open and closed fittings using real ear measurements. RESULTS Externalization ratings were significantly higher for unaided than aided listening and for open versus closed domes. Similarly, own-voice ratings tended to be higher for unaided versus aided listening and for open versus closed domes. Although these broad patterns suggest that reduced ratings are associated with more occlusion, objective measures of occlusion did not account for a significant amount of the variance in either kind of rating. Similarly, individual own-voice ratings did not significantly predict individual externalization ratings. The data obtained with hearing aid users wearing their own devices suggested that regularly worn devices can have positive effects on own-voice perception while disrupting externalization. CONCLUSIONS Overall, compared with unaided listening, hearing aids negatively affected externalization and own-voice perception, with larger effects for closed than open fittings. However, at the individual level, measures of occlusion and sound externalization were not strongly related.

Physiological and subjective evaluation of music processing strategies for hearing-impaired listeners: a pilot study

Hearing loss affects over 2.5 billion people worldwide and significantly degrades music enjoyment. While advances in digital signal processing (DSP) aim to improve listening experiences, their combined effects on perceived audio quality and physiological engagement remain underexplored. This pilot study evaluated hearing-impairment-optimised DSP models from the CADENZA challenge. Eleven participants (eight normal-hearing, three hearing-aid users) listened to musical excerpts processed via four DSP algorithms using circumaural open-back headphones in a semi-anechoic chamber. Signal delivery was tailored using personalized audiogram baselines and volume attenuation. Subjective metrics, Basic Audio Quality (BAQ) and likeability, were collected alongside continuous physiological recordings (electrodermal activity [EDA] and photoplethysmography [PPG]) captured with a medical-grade wrist wearable. DSP model E021 consistently achieved the highest BAQ and likeability scores across both participant groups, with BAQ and likeability demonstrating a strong positive correlation. Physiological monitoring revealed exploratory associations between autonomic arousal and variability metrics: specifically, phasic EDA variability and inter-beat interval (IBI) variability positively correlated with both BAQ and likeability. Variability-based physiological markers present viable pathways for evaluating subjective listener responses in small cohorts. Integrating wearable-derived biometric signals with subjective appraisal provides a framework for developing adaptive, listener-aware DSP strategies that enhance music accessibility for individuals with hearing impairment.