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This paper presents the Cadenza Woodwind Dataset. This publicly available data is synthesised audio for woodwind quartets including renderings of each instrument in isolation. The data was created to be used as training data within Cadenza's second open machine learning challenge (CAD2) for the task on rebalancing classical music ensembles. The dataset is also intended for developing other music information retrieval (MIR) algorithms using machine learning. It was created because of the lack of large-scale datasets of classical woodwind music with separate audio for each instrument and permissive license for reuse. Music scores were selected from the OpenScore String Quartet corpus. These were rendered for two woodwind ensembles of (i) flute, oboe, clarinet and bassoon; and (ii) flute, oboe, alto saxophone and bassoon. This was done by a professional music producer using industry-standard software. Virtual instruments were used to create the audio for each instrument using software that interpreted expression markings in the score. Convolution reverberation was used to simulate a performance space and the ensembles mixed. The dataset consists of the audio and associated metadata., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Introduction: Previous work on audio quality evaluation has demonstrated a developing convergence of the key perceptual attributes underlying judgments of quality, such as timbral, spatial and technical attributes. However, across existing research there remains a limited understanding of the crucial perceptual attributes that inform audio quality evaluation for people with hearing loss, and those who use hearing aids. This is especially the case with music, given the unique problems it presents in contrast to human speech., Method: This paper presents a sensory evaluation study utilising descriptive analysis methods, in which a panel of hearing aid users collaborated, through consensus, to identify the most important perceptual attributes of music audio quality and developed a series of rating scales for future listening tests. Participants ( N = 12), with a hearing loss ranging from mild to severe, first completed an online elicitation task, providing single-word terms to describe the audio quality of original and processed music samples; this was completed twice by each participant, once with hearing aids, and once without. Participants were then guided in discussing these raw terms across three focus groups, in which they reduced the term space, identified important perceptual groupings of terms, and developed perceptual attributes from these groups (including rating scales and definitions for each)., Results: Findings show that there were seven key perceptual dimensions underlying music audio quality ( clarity , harshness , distortion , spaciousness , treble strength , middle strength , and bass strength ), alongside a music audio quality attribute and possible alternative frequency balance attributes., Discussion: We outline how these perceptual attributes align with extant literature, how attribute rating instruments might be used in future work, and the importance of better understanding the music listening difficulties of people with varied profiles of hearing loss., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Bannister, Greasley, Cox, Akeroyd, Barker, Fazenda, Firth, Graetzer, Roa Dabike, Vos and Whitmer.)

Objective: The purpose of this study was to investigate alpha power as an objective measure of effortful listening in continuous speech with scalp and ear-EEG., Methods: Scalp and ear-EEG were recorded simultaneously during presentation of a 33-s news clip in the presence of 16-talker babble noise. Four different signal-to-noise ratios (SNRs) were used to manipulate task demand. The effects of changes in SNR were investigated on alpha event-related synchronization (ERS) and desynchronization (ERD). Alpha activity was extracted from scalp EEG using different referencing methods (common average and symmetrical bi-polar) in different regions of the brain (parietal and temporal) and ear-EEG., Results: Alpha ERS decreased with decreasing SNR (i.e., increasing task demand) in both scalp and ear-EEG. Alpha ERS was also positively correlated to behavioural performance which was based on the questions regarding the contents of the speech., Conclusion: Alpha ERS/ERD is better suited to track performance of a continuous speech than listening effort., Significance: EEG alpha power in continuous speech may indicate of how well the speech was perceived and it can be measured with both scalp and Ear-EEG.

About one-third of all recently published studies on listening effort have used at least one physiological measure, providing evidence of the popularity of such measures in listening effort research. However, the specific measures employed, as well as the rationales used to justify their inclusion, vary greatly between studies, leading to a literature that is fragmented and difficult to integrate. A unified approach that assesses multiple psychophysiological measures justified by a single rationale would be preferable because it would advance our understanding of listening effort. However, such an approach comes with a number of challenges, including the need to develop a clear definition of listening effort that links to specific physiological measures, customized equipment that enables the simultaneous assessment of multiple measures, awareness of problems caused by the different timescales on which the measures operate, and statistical approaches that minimize the risk of type-I error inflation. This article discusses in detail the various obstacles for combining multiple physiological measures in listening effort research and provides recommendations on how to overcome them., Competing Interests: Conflict of Interest There are no conflicts of interest, financial, or otherwise., (Thieme. All rights reserved.)

Objectives: The Glasgow Benefit Inventory (GBI) has been extensively used to report the benefit from otolaryngological surgery. Benefit from non-surgical management has not been reported, despite this being the outcome of most otolaryngology and audiology consultations., Design: GBI responses from 4543 adults from the Scottish ENT Outcome Study were categorised by diagnosis. Benefit scores for different interventions within diagnostic categories for which surgery was not a potential management are reported using the revised 5-factor Glasgow Benefit Inventory (GBI-5F; 15 questions and 5 factors)., Setting: Adult otolaryngology outpatient clinics in six university hospitals., Participants: Adults seen with conditions that had no surgical option and given non-surgical management., Results: Overall, 80% of participants managed in Scottish Ear Nose and Throat Outcome Study (SENTOS) did not have surgery. A total of 1373 (30%) participants with various diagnoses were given reassurance and advice with no active intervention. There was no change in their GBI-5F total or factor scores, suggesting that they did not come to harm from their lack of active intervention. Hearing aids for bilateral sensorineural hearing loss gave greater benefit than reassurance in all factors, though individuals with a conductive impairment reported greater benefit in the Quality of life factor than those with a sensorineural impairment. Hearing aids and maskers produced benefit in the Support factor for patients with tinnitus. Epley's manoeuvre for benign paroxysmal positional vertigo gave benefit in the total score and the Quality of life factor compared with reassurance. Systemic medication for laryngo-pharyngeal reflux and topical medication for otitis externa gave no greater benefit in any factor or the total score compared with reassurance., Conclusion: The GBI-5F and its five factors give useful information for reporting the benefit of non-surgical interventions in adult otolaryngology and audiology clinics., (© 2022 The Authors. Clinical Otolaryngology published by John Wiley & Sons Ltd.)

Objectives: In the personalisation of hearing-aid fittings, gain is often adjusted to suit patient preferences using live speech. When using brief sentences as stimuli, the minimum gain adjustments necessary to elicit consistent preferences ("preference thresholds") were previously found to be much greater than typical adjustments in current practice. The current study examined the role of duration on preference thresholds., Design: Participants heard 2, 4 and 6-s segments of a continuous monologue presented successively in pairs. The first segment of each pair was presented at each individual's real-ear or prescribed gain. The second segment was presented with a ±0-12 dB gain adjustment in one of three frequency bands. Participants judged whether the second was "better", "worse" or "no different" from the first., Study Sample: Twenty-nine adults, all with hearing-aid experience., Results: The minimum gain adjustments needed to elicit "better" or "worse" judgments decreased with increasing duration for most adjustments. Inter-participant agreement and intra-participant reliability increased with increasing duration up to 4 s, then remained stable., Conclusions: Providing longer stimuli improves the likelihood of patients providing reliable judgments of hearing-aid gain adjustments, but the effect is limited, and alternative fitting methods may be more viable for effective hearing-aid personalisation.

Objective: Hearing rehabilitation attempts to compensate for auditory dysfunction, reduce hearing difficulties and minimise participation restrictions that can lead to social isolation. However, there is no systematic approach to assess the quality of the intervention at an individual level that might help to evaluate the need of further hearing rehabilitation in the hearing care clinic., Design: A data-driven analysis on subjective data reflecting hearing disabilities and handicap was chosen to explore "benefit patterns" as a result of rehabilitation in different audiometric groups. The method was based on (1) dimensionality reduction; (2) stratification; (3) archetypal analysis; (4) clustering; (5) item importance estimation., Study Sample: 572 hearing-aid users completed questionnaires of hearing difficulties (speech, spatial and qualities hearing scale; SSQ) and hearing handicap (HHQ)., Results: The data-driven approach revealed four benefit profiles that were different for each audiometric group. The groups with low degree of high-frequency hearing loss (HL HF ) showed a priority for rehabilitating hearing handicaps, whereas the groups with HL HF > 50 dB HL showed a priority for improvements in speech understanding., Conclusions: The patterns of benefit and the stratification approach might guide the clinical intervention strategy and improve the efficacy and quality of service in the hearing care clinic.

Objectives: Current hearing aids have a limited bandwidth, which limits the intelligibility and quality of their output, and inhibits their uptake. Recent advances in signal processing, as well as novel methods of transduction, allow for a greater useable frequency range. Previous studies have shown a benefit for this extended bandwidth in consonant recognition, talker-sex identification, and separating sound sources. To explore whether there would be any direct spatial benefits to extending bandwidth, we used a dynamic localization method in a realistic situation., Design: Twenty-eight adult participants with minimal hearing loss reoriented themselves as quickly and accurately as comfortable to a new, off-axis near-field talker continuing a story in a background of far-field talkers of the same overall level in a simulated large room with common building materials. All stimuli were low-pass filtered at either 5 or 10 kHz on each trial. To further simulate current hearing aids, participants wore microphones above the pinnae and insert earphones adjusted to provide a linear, zero-gain response., Results: Each individual trajectory was recorded with infra-red motion-tracking and analyzed for accuracy, duration, start time, peak velocity, peak velocity time, complexity, reversals, and misorientations. Results across listeners showed a significant increase in peak velocity and significant decrease in start and peak velocity time with greater (10 kHz) bandwidth., Conclusions: These earlier, swifter orientations demonstrate spatial benefits beyond static localization accuracy in plausible conditions; extended bandwidth without pinna cues provided more salient cues in a realistic mixture of talkers., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2021 The Authors. Ear & Hearing is published on behalf of the American Auditory Society, by Wolters Kluwer Health, Inc.)

Clinical trials are designed to evaluate interventions that prevent, diagnose or treat a health condition and provide the evidence base for improving practice in health care. Many health professionals, including those working within or allied to hearing health, are expected to conduct or contribute to clinical trials. Recent systematic reviews of clinical trials reveal a dearth of high quality evidence in almost all areas of hearing health practice. By providing an overview of important steps and considerations concerning the design, analysis and conduct of trials, this article aims to give guidance to hearing health professionals about the key elements that define the quality of a trial. The article starts out by situating clinical trials within the greater scope of clinical evidence, then discusses the elements of a PICO-style research question. Subsequently, various methodological considerations are discussed including design, randomization, blinding, and outcome measures. Because the literature on outcome measures within hearing health is as confusing as it is voluminous, particular focus is given to discussing how hearing-related outcome measures affect clinical trials. This focus encompasses how the choice of measurement instrument(s) affects interpretation, how the accuracy of a measure can be estimated, how this affects the interpretation of results, and if differences are statistically, perceptually and/or clinically meaningful to the target population, people with hearing loss., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Munro, Whitmer and Heinrich.)

Objective: Patient-reported outcomes can be useful for reporting benefit from non-life-saving interventions, but often they report a single overall score, which means that much information on the specific areas of benefit is lost. Our aim was to perform a new factor analysis on the Glasgow Children's Benefit Inventory (GCBI) to create subscales reflecting domains of benefit. Further aims were to assess the internal consistency of the GCBI, and to develop guidelines for reporting both a total score and sub-scales in future studies., Methods: We collected 4 existing datasets of GCBI data from children who have undergone tonsillectomy, ventilation tube insertion, pinnaplasty, and submucous diathermy to the inferior turbinates. We performed exploratory factor analysis with principal axis factoring with varimax rotation, we sought redundancy in question items, and we measured internal consistency., Results: Using the combined dataset of 772 cases, we found 4 factors which accounted for 64% of the variance and which we have labeled "Psycho-social," "Physical health," "Behavior," and "Vitality." Subscale results varied in predictable ways depending on the nature of the intervention. Cronbach's alpha was 0.928. Item-total correlations were high, and no item could be deleted to improve alpha. Floor effects were apparent for various questions but were not consistent between different interventions., Conclusions: The GCBI contains a range of questions which each add value in different clinical interventions. We can now make recommendations for reporting the results of the GCBI and its 4 new subscales.

Objectives: Hearing-aid frequency-gain responses are routinely adjusted by clinicians to patient preferences and descriptions. This study measured the minimum gain adjustments required to elicit preferences, and the assignment of descriptors to gain adjustments, to perceptually evaluate description-based troubleshooting., Design: Participants judged whether short sentences with ±0-12 dB gain adjustments in one of three frequency bands were "better", "worse" or "no different" from the same sentence at their individual real-ear or prescribed gain. If judged "better" or "worse", participants were then asked to assign one of the six common sound-quality descriptors to their preference., Study Sample: Thirty-two adults (aged 51-75 years) all with hearing-aid experience., Results: Median preference thresholds, the minimum gain adjustments to elicit "better" or "worse" judgments, ranged from 4 to 12 dB, increasing with frequency. There was some between-participant agreement in preferences: participants generally preferred greater low-frequency gain. Within-participant reliability for preferences was moderate. There was, however, little between-participant agreement in descriptor selection for gain adjustments. Furthermore, within-participant reliability for descriptor selection was lacking., Conclusions: The scale of gain adjustments necessary to elicit preferences, along with the low agreement and reliability in descriptors for these adjustments questions the efficiency and efficacy of current description-based troubleshooting, especially with short speech stimuli.

Many conversations in our day-to-day lives are held in noisy environments - impeding comprehension, and in groups - taxing auditory attention-switching processes. These situations are particularly challenging for older adults in cognitive and sensory decline. In noisy environments, a variety of extra-linguistic strategies are available to speakers and listeners to facilitate communication, but while models of language account for the impact of context on word choice, there has been little consideration of the impact of context on extra-linguistic behaviour. To address this issue, we investigate how the complexity of the acoustic environment and interaction situation impacts extra-linguistic conversation behaviour of older adults during face-to-face conversations. Specifically, we test whether the use of intelligibility-optimising strategies increases with complexity of the background noise (from quiet to loud, and in speech-shaped vs. babble noise), and with complexity of the conversing group (dyad vs. triad). While some communication strategies are enhanced in more complex background noise, with listeners orienting to talkers more optimally and moving closer to their partner in babble than speech-shaped noise, this is not the case with all strategies, as we find greater vocal level increases in the less complex speech-shaped noise condition. Other behaviours are enhanced in the more complex interaction situation, with listeners using more optimal head orientations, and taking longer turns when gaining the floor in triads compared to dyads. This study elucidates how different features of the conversation context impact individuals' communication strategies, which is necessary to both develop a comprehensive cognitive model of multimodal conversation behaviour, and effectively support individuals that struggle conversing.

Objectives: To review, using confirmatory factor analysis, the widely used 18-question Glasgow Benefit Inventory [GBI] that has three factors. Thereafter to develop, using exploratory factor analysis, a more coherent, revised version of the GBI., Design: Confirmatory and exploratory factor analysis of a large national GBI data set of ORL interventions., Setting: Adult otorhinolaryngology outpatient clinics in six University Hospital departments., Participants: One thousand nine hundred eighty adult patients who had complete GBI data and who underwent an active (medical or surgical) intervention, out of the total data set of 9005 patients from the original Scottish ENT Outcome Study [SENTOS]., Results: One of the 18 questions was discarded from the data base because it was not answered by 8% of respondents. Two of the original factors remained (Physical Health, renamed General Health, and Social Support, renamed Support). The General factor was split into three new factors (Quality of Life, Self-Confidence and Social Involvement). The three new factors were found to give additional information regarding the area of benefit. This reduced number of questions does not make any material difference to the results of the >196 existing GBI papers in the literature., Conclusion: A 15-question GBI with five factors is provided that is more explanatory of the areas of benefit., (© 2020 The Authors. Clinical Otolaryngology published by John Wiley & Sons Ltd.)

Individuals with hearing loss allocate cognitive resources to comprehend noisy speech in everyday life scenarios. Such a scenario could be when they are exposed to ongoing speech and need to sustain their attention for a rather long period of time, which requires listening effort. Two well-established physiological methods that have been found to be sensitive to identify changes in listening effort are pupillometry and electroencephalography (EEG). However, these measurements have been used mainly for momentary, evoked or episodic effort. The aim of this study was to investigate how sustained effort manifests in pupillometry and EEG, using continuous speech with varying signal-to-noise ratio (SNR). Eight hearing-aid users participated in this exploratory study and performed a continuous speech-in-noise task. The speech material consisted of 30-second continuous streams that were presented from loudspeakers to the right and left side of the listener (±30° azimuth) in the presence of 4-talker background noise (+180° azimuth). The participants were instructed to attend either to the right or left speaker and ignore the other in a randomized order with two different SNR conditions: 0 dB and -5 dB (the difference between the target and the competing talker). The effects of SNR on listening effort were explored objectively using pupillometry and EEG. The results showed larger mean pupil dilation and decreased EEG alpha power in the parietal lobe during the more effortful condition. This study demonstrates that both measures are sensitive to changes in SNR during continuous speech., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The commercial affiliation of authors CG, DW, EA and TL does not alter our adherence to PLOS ONE policies on sharing data and materials.

How do people have conversations in noise and make themselves understood? While many previous studies have investigated speaking and listening in isolation, this study focuses on the behaviour of pairs of individuals in an ecologically valid context. Specifically, we report the fine-grained dynamics of natural conversation between interlocutors of varying hearing ability (n = 30), addressing how different levels of background noise affect speech, movement, and gaze behaviours. We found that as noise increased, people spoke louder and moved closer together, although these behaviours provided relatively small acoustic benefit (0.32 dB speech level increase per 1 dB noise increase). We also found that increased noise led to shorter utterances and increased gaze to the speaker's mouth. Surprisingly, interlocutors did not make use of potentially beneficial head orientations. While participants were able to sustain conversation in noise of up to 72 dB, changes in conversation structure suggested increased difficulty at 78 dB, with a significant decrease in turn-taking success. Understanding these natural conversation behaviours could inform broader models of interpersonal communication, and be applied to the development of new communication technologies. Furthermore, comparing these findings with those from isolation paradigms demonstrates the importance of investigating social processes in ecologically valid multi-person situations.

Frequency-dependent gain adjustments are routine in hearing-aid fittings, whether in matching to real-ear targets or fine-tuning to patient feedback. Patient feedback may be unreliable and fittings inefficient if adjustments are not discriminable. To examine what gain adjustments are discriminable, we measured the just-noticeable differences (JNDs) for level increments in speech-shaped noises processed with prescription gains. JNDs were measured in the better ears of 38 participants with hearing impairment using a fixed-level, same-different task. JNDs were measured for increments at six individual frequency-bands: a 0.25-kHz low-pass band; octave-wide bands at 0.5, 1, 2, and 4 kHz; and a 6-kHz high-pass band. JNDs for broadband increments were also measured. JNDs were estimated at d' of 1 for a minimally discriminable increment in optimal laboratory conditions. The JND for frequency-band increments was 2.8 dB excluding the 0.25-kHz low-pass band, for which the JND was 4.5 dB. The JND for broadband increments was 1.5 dB. Participants' median frequency-band and broadband JNDs were positively correlated. JNDs were mostly independent of age, pure-tone thresholds, and cognitive score. In consideration of self-fitting adjustments in noisier conditions, JNDs were additionally estimated at a more sensitive d' of 2. These JNDs were 6 dB for bands below 1 kHz, and 5 dB for bands at and above 1 kHz. Overall, the results suggest noticeable fine-tuning adjustments of 3 dB and self-fitting adjustments of 5 dB.

Background: Tonsillitis is a common condition with an incidence in UK general practice of 37 per 1000 population a year. 1 Recurrent tonsillitis results in significant morbidity and impacts on individuals' quality of life. This study assesses the morbidity and quality of life of adults with recurrent tonsillitis, and the impact of surgical intervention on their health state., Objectives: To describe disease-specific and global quality of life for adults with recurrent tonsillitis 6 months after tonsillectomy, using two instruments: the health impact of throat problems (HITP) and EuroQol-visual analogue scale questionnaire. To assess the overall health benefit from tonsillectomy as an intervention using the Glasgow Benefit Inventory (GBI). To assess potential predictors of tonsillectomy benefit., Design: A prospective, observational cohort audit of patients who have fulfilled Scottish Intercollegiate Guideline Network (SIGN) criteria for tonsillectomy. 2 SETTING: Secondary care, teaching hospital., Participants: Seventy patients (57 female), median age 20 years (range 13-41)., Results: Median preoperative HITP was 47 (range 15-67), compared to 4 (0-72), (P<.001) 6 months following surgery. Median HITP difference was 39.5 (range -20 to 75). There was no significant change in global Quality of Life. Median overall 6 months GBI was 39 (-3 to 100). Patients had an average of 27 episodes of tonsillitis over a period of seven years before "achieving" tonsillectomy, significantly higher than the SIGN guidelines of three or more episodes over three years., Conclusions: Recurrent tonsillitis causes a poor disease-specific quality of life. Patients experienced a median of three episodes per year for seven years before tonsillectomy. Following tonsillectomy, patients had a significant improvement in their disease-specific quality of life. Baseline HITP significantly improved after tonsillectomy. The results imply patients with recurrent acute tonsillitis may be experiencing undue delay., (© 2017 John Wiley & Sons Ltd.)

Tinnitus has been linked to noise exposure, a common form of which is listening to music as a leisure activity. The relationship between tinnitus and type and duration of music exposure is not well understood. We conducted an internet-based population study that asked participants questions about lifetime music exposure and hearing, and included a hearing test involving speech intelligibility in noise, the High Frequency Digit Triplets Test. 4950 people aged 17-75 years completed all questions and the hearing test. Results were analyzed using multinomial regression models. High exposure to leisure music, hearing difficulty, increasing age and workplace noise exposure were independently associated with increased tinnitus. Three forms of music exposure (pubs/clubs, concerts, personal music players) did not differ in their relationship to tinnitus. More males than females reported tinnitus. The objective measure of speech reception threshold had only a minimal relationship with tinnitus. Self-reported hearing difficulty was more strongly associated with tinnitus, but 76% of people reporting usual or constant tinnitus also reported little or no hearing difficulty. Overall, around 40% of participants of all ages reported never experiencing tinnitus, while 29% reported sometimes, usually or constantly experiencing tinnitus that lasted more than 5 min. Together, the results suggest that tinnitus is much more common than hearing loss, but that there is little association between the two, especially among the younger adults disproportionately sampled in this study., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

The speech-to-noise ratio (SNR) in an environment plays a vital role in speech communication for both normal-hearing (NH) and hearing-impaired (HI) listeners. While hearing-assistance devices attempt to deliver as favorable an SNR as possible, there may be discrepancies between noticeable and meaningful improvements in SNR. Furthermore, it is not clear how much of an SNR improvement is necessary to induce intervention-seeking behavior. Here, we report on a series of experiments examining the just-meaningful difference (JMD) in SNR. All experiments used sentences in same-spectrum noise, with two intervals on each trial mimicking examples of pre- and post-benefit situations. Different groups of NH and HI adults were asked (a) to rate how much better or worse the change in SNR was in a number of paired examples, (b) if they would swap the worse for the better SNR (e.g., their current device for another), or (c) if they would be willing to go to the clinic for the given increase in SNR. The mean SNR JMD based on better or worse ratings (one arbitrary unit) was similar to the just-noticeable difference, approximately 3 dB. However, the mean SNR JMD for the more clinically relevant tasks-willingness (at least 50% of the time) to swap devices or attend the clinic for a change in SNR--was 6 to 8 dB regardless of hearing ability. This SNR JMD of the order of 6 dB provides a new benchmark, indicating the SNR improvement necessary to immediately motivate participants to seek intervention., (© The Author(s) 2016.)

The most important parameter that affects the ability to hear and understand speech in the presence of background noise is the signal-to-noise ratio (SNR). Despite decades of research in speech intelligibility, it is not currently known how much improvement in SNR is needed to provide a meaningful benefit to someone. We propose that the underlying psychophysical basis to a meaningful benefit should be the just noticeable difference (JND) for SNR. The SNR JND was measured in a series of experiments using both adaptive and fixed-level procedures across participants of varying hearing ability. The results showed an average SNR JND of approximately 3 dB for sentences in same-spectrum noise. The role of the stimulus and link to intelligibility was examined by measuring speech-intelligibility psychometric functions and comparing the intelligibility JND estimated from those functions with measured SNR JNDs. Several experiments were then conducted to establish a just meaningful difference (JMD) for SNR. SNR changes that could induce intervention-seeking behaviour for an individual were measured with subjective scaling and report, using the same stimuli as the SNR JND experiment as pre- and post-benefit examples. The results across different rating and willingness-to-change tasks showed that the mean ratings increased near linearly with a change in SNR, but a change of at least 6 dB was necessary to reliably motivate participants to seek intervention. The magnitude of the JNDs and JMDs for speech-intelligibility benefits measured here suggest a gap between what is achievable and what is meaningful.

Sound sources at the same angle in front or behind a two-microphone array (e.g., bilateral hearing aids) produce the same time delay and two estimates for the direction of arrival: A front-back confusion. The auditory system can resolve this issue using head movements. To resolve front-back confusion for hearing-aid algorithms, head movement was measured using an inertial sensor. Successive time-delay estimates between the microphones are shifted clockwise and counterclockwise by the head movement between estimates and aggregated in two histograms. The histogram with the largest peak after multiple estimates predicted the correct hemifield for the source, eliminating the front-back confusions.

Just-noticeable differences (JNDs) have been measured for various features of sounds, but despite its importance to communication, there is no benchmark for what is a just-noticeable-and possibly meaningful-difference in speech-to-noise ratio (SNR). SNR plays a crucial role in speech communication for normal-hearing and hearing-impaired listeners. Difficulty hearing speech in background noise-a poor SNR-often leads to dissatisfaction with hearing-assistance devices. While such devices attempt through various strategies to address this problem, it is not currently known how much improvement in SNR is needed to provide a noticeable benefit. To investigate what is a noticeable benefit, we measured the JND in SNR for both normal-hearing and hearing-impaired listeners. Here, we report the SNR JNDs of 69 participants of varying hearing ability, estimated using either an adaptive or fixed-level procedure. The task was to judge which of the two intervals containing a sentence in speech-spectrum noise presented over headphones was clearer. The level of each interval was roved to reduce the influence of absolute level cues. The results of both procedures showed an average SNR JND of 3 dB that was independent of hearing ability. Further experiments using a subset of normal-hearing listeners showed that level roving does elevate threshold. These results suggest that noise reduction schemes may need to achieve a benefit greater than 3 dB to be reliably discriminable., (© The Author(s) 2015.)

Objectives: Although directional microphones on a hearing aid provide a signal-to-noise ratio benefit in a noisy background, the amount of benefit is dependent on how close the signal of interest is to the front of the user. It is assumed that when the signal of interest is off-axis, users can reorient themselves to the signal to make use of the directional microphones to improve signal-to-noise ratio. The present study tested this assumption by measuring the head-orienting behavior of bilaterally fit hearing-impaired individuals with their microphones set to omnidirectional and directional modes. The authors hypothesized that listeners using directional microphones would have greater difficulty in rapidly and accurately orienting to off-axis signals than they would when using omnidirectional microphones., Design: The authors instructed hearing-impaired individuals to turn and face a female talker in simultaneous surrounding male-talker babble. Participants pressed a button when they felt they were accurately oriented in the direction of the female talker. Participants completed three blocks of trials with their hearing aids in omnidirectional mode and three blocks in directional mode, with mode order randomized. Using a Vicon motion tracking system, the authors measured head position and computed fixation error, fixation latency, trajectory complexity, and proportion of misorientations., Results: Results showed that for larger off-axis target angles, listeners using directional microphones took longer to reach their targets than they did when using omnidirectional microphones, although they were just as accurate. They also used more complex movements and frequently made initial turns in the wrong direction. For smaller off-axis target angles, this pattern was reversed, and listeners using directional microphones oriented more quickly and smoothly to the targets than when using omnidirectional microphones., Conclusions: The authors argue that an increase in movement complexity indicates a switch from a simple orienting movement to a search behavior. For the most off-axis target angles, listeners using directional microphones appear to not know which direction to turn, so they pick a direction at random and simply rotate their heads until the signal becomes more audible. The changes in fixation latency and head orientation trajectories suggest that the decrease in off-axis audibility is a primary concern in the use of directional microphones, and listeners could experience a loss of initial target speech while turning toward a new signal of interest. If hearing-aid users are to receive maximum directional benefit in noisy environments, both adaptive directionality in hearing aids and clinical advice on using directional microphones should take head movement and orientation behavior into account.

In a previous study [Whitmer, Seeber and Akeroyd, J. Acoust. Soc. Am. 132, 369-379 (2012)], it was demonstrated that older hearing-impaired (HI) listeners produced visual sketches of headphone-presented noises that were insensitive to changes in interaural coherence. The current study further explores this insensitivity by comparing (a) binaural temporal fine-structure (TFS) resolution and (b) sound localization precision to (c) auditory source width judgments. Thirty-five participants aged 26-81 years with normal to moderately impaired hearing (a) discriminated interaurally phase-shifted tones from diotic tones presented over headphones, (b) located 500-ms speech-spectrum filtered click trains presented over loudspeakers between ±30° in quiet, and (c) sketched the perceived width of low-pass, high-pass, and speech-spectrum noise stimuli presented over loudspeakers from 0° and simultaneously from ±45° at attenuations of 0-20 dB to generate partially coherent stimuli. The results showed a decreasing sensitivity to width with age and impairment which was related to binaural TFS threshold: the worse one's threshold-which was correlated with age-the less the perceived width increased with decreasing interaural coherence. These results suggest that senescent changes to the auditory system do not necessarily lead to perceptions of broader, more diffuse sound images based on interaural coherence.

Objective: To form a normative set of responses to the GHABP questionnaire from a large regional dataset., Design: Participants were asked to rate their hearing disability, handicap, hearing-aid (HA) use, HA benefit, HA satisfaction, and residual (aided) disability on a five-point scale for four situations: quiet conversation, television (TV) listening, noisy conversation, and group conversation. A subset of participants also estimated the time spent in these situations., Study Sample: A group of 1574 adults with normal to profound hearing thresholds participated., Results: There was a significant relationship between increasing perceived disability and increasing hearing loss as given by the better-ear audiometric average (BEA). Responses for HA measures did not vary greatly with hearing loss: HA use was reported as high, whereas residual disability, HA benefit, and satisfaction were all reported on average as moderate., Conclusions: The results can be used as a normative dataset with which to evaluate individual responses in the clinic, where the GHABP provides a useful short-form questionnaire to engage the patient. The lack of systematic changes in hearing-aid related responses shows room for improvement in the benefit afforded by amplification.

The science of how we use interaural differences to localise sounds has been studied for over a century and in many ways is well understood. But in many of these psychophysical experiments listeners are required to keep their head still, as head movements cause changes in interaural level and time differences (ILD and ITD respectively). But a fixed head is unrealistic. Here we report an analysis of the actual ILDs and ITDs that occur as people naturally move and relate them to gyroscope measurements of the actual motion. We used recordings of binaural signals in a number of rooms and listening scenarios (home, office, busy street etc). The listener's head movements were also recorded in synchrony with the audio, using a micro-electromechanical gyroscope. We calculated the instantaneous ILD and ITDs and analysed them over time and frequency, comparing them with measurements of head movements. The results showed that instantaneous ITDs were widely distributed across time and frequency in some multi-source environments while ILDs were less widely distributed. The type of listening environment affected head motion. These findings suggest a complex interaction between interaural cues, egocentric head movement and the identification of sound sources in real-world listening situations.

In previous studies we have shown that older hearing-impaired individuals are relatively insensitive to changes in the apparent width of broadband noises when those width changes were based on differences in interaural coherence [W. Whitmer, B. Seeber and M. Akeroyd, J. Acoust. Soc. Am. 132, 369-379 (2012)]. This insensitivity has been linked to senescent difficulties in resolving binaural fine-structure differences. It is therefore possible that interaural coherence, despite its widespread use, may not be the best acoustic surrogate of spatial perception for the aged and impaired. To test this, we simulated the room impulse responses for various acoustic scenarios with differing coherence and lateral (energy) fraction attributes using room modelling software (ODEON). Bilaterally impaired adult participants were asked to sketch the perceived size of speech tokens and musical excerpts that were convolved with these impulse responses and presented to them in a sound-dampened enclosure through a 24-loudspeaker array. Participants' binaural acuity was also measured using an interaural phase discrimination task. Corroborating our previous findings, the results showed less sensitivity to interaural coherence in the auditory source width judgments of older hearing-impaired individuals, indicating that alternate acoustic measurements in the design of spaces for the elderly may be necessary.

Objectives: To determine the sensitivity and specificity of the whispered voice test (WVT) in detecting hearing loss when administered by practitioners with different levels of experience., Design: Diagnostic accuracy study of WVT, through acoustic analysis of whispers of experienced and inexperienced practitioners (experiment 1) and behavioural validation of these recordings (experiment 2)., Setting: Research institute with a pool of patients sourced from local clinics in the Greater Glasgow area., Participants: 22 people had their whispers recorded and analysed in experiment 1; 4 older experienced (OE), 4 older inexperienced (OI) and 14 younger inexperienced (YI). In experiment 2, 73 people (112 individual ears) took part in a digit recognition task using 2 OE and 2 YI whisperers from experiment 1., Main Outcome Measures: Average level (dB sound pressure level) across frequency, average level across all utterances (dB A) and within/across-digit deviation (dB A) for experiment 1. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of WVT for experiment 2., Results: In experiment 1, OE whisperers were 8-10 dB more intense than inexperienced whisperers across all whispered utterances. Variability was low and comparable regardless of age or experience. In experiment 2, at an optimum threshold of 40 dB HL, sensitivity and specificity were 63% (95% CI of 58% to 68%) and 93% (92% to 94%), respectively, for OE whisperers. PPV was 56% (51% to 61%), NPV was 95% (94% to 96%). For YI whisperers at an optimum threshold of 29 dB HL, sensitivity and specificity were 80% (78% to 82%) and 52% (50% to 55%), respectively. PPV was 65% (63% to 67%) and NPV was 70% (67% to 72%)., Conclusions: WVT is an effective screening test, providing the level of the whisperer is considered when setting the test's hearing-loss criterion. Possible implications are voice measurement while training for inexperienced whisperers.

It is often assumed that single sources of sound are perceived as being punctate, but this cannot be guaranteed, especially for hearing-impaired listeners. Any impairment that gives a reduction at the periphery in the accuracy of coding fine-scale temporal information must give a slight interaural jitter in the temporal information passed to higher centres, and so would be expected to lead to an effective reduction in the interaural coherence (IC) of any stimulus. This would lead to deficits in locating sounds, but deficits of imprecision, not inaccuracy. In turn, this implies that older hearing-impaired individuals should have a diminished perception of auditory space, affecting their abilities to perceive clear, concise, punctate spatial impressions or to separate sounds by location. The current work tested this hypothesis by using two separate visual-analogy methods to measure auditory source width for broadband sounds. In one method, the listener sketched the auditory image, a visual-description task, and for the other, the listener selected the closest one of a set of pre-drawn visual sketches (note that the first is an open-set experiment, whereas the second is a closed-set experiment). We found that older hearing-impaired listeners had increased difficulty in judging changes in interaural coherence, showing a corresponding insensitivity to auditory source width in the visual-analogy tasks.

Previous studies have shown a loss in the precision of horizontal localization responses of older hearing-impaired (HI) individuals, along with potentially poorer neural representations of sound-source location. These deficits could be the result or corollary of greater difficulties in discriminating spatial images, and the insensitivity to punctate sound sources. This hypothesis was tested in three headphone-presentation experiments varying interaural coherence (IC), the cue most associated with apparent auditory source width. First, thresholds for differences in IC were measured for a broad sampling of participants. Older HI participants were significantly worse at discriminating IC across reference values than younger normal-hearing participants. These results are consistent with senescent increases in temporal jitter. Performance decreased with age, a finding corroborated in a second discrimination experiment using a separate group of participants matched for hearing loss. This group also completed a third, visual experiment, with both a cross-mapping task where they drew the size of the sound they heard and the identification task where they chose the image that best corresponded to what they heard. The results from the visual tasks indicate that older HI individuals do not hear punctate images and are relatively insensitive to changes in width based on IC.

Hearing-aid wearers have reported sound source locations as being perceptually internalized (i.e., inside their head). The contribution of hearing-aid design to internalization has, however, received little attention. This experiment compared the sensitivity of hearing-impaired (HI) and normal-hearing listeners to externalization cues when listening with their own ears and simulated behind-the-ear hearing-aids in increasingly complex listening situations and reduced pinna cues. Participants rated the degree of externalization using a multiple-stimulus listening test for mixes of internalized and externalized speech stimuli presented over headphones. The results showed that HI listeners had a contracted perception of externalization correlated with high-frequency hearing loss., (© 2012 Acoustical Society of America)

Objective: This study measured the effects of two previously untested practical considerations-venting and transmission delays-on speech intelligibility in a simulated unilateral wireless system, where a target signal in background noise was transmitted wirelessly to the hearing-impaired (HI) listener., Design: Speech reception thresholds (SRTs) relative to the signal-to-noise ratio (SNR) were measured by varying the surrounding babble noise level. The target signal was presented at 0° azimuth in the soundfield and unilaterally via an insert earphone, using open and closed fittings with simulated-wireless delays ranging between 0-160 ms. SRTs were also measured unaided and with participants' current hearing aid(s)., Study Sample: Thirty-three mild-to-moderate sensorineural HI adults participated in the experiment., Results: For an open fitting, the results showed a 5-dB SNR benefit in SRT compared to unaided performance at shorter delays. For a closed fitting, the majority of participants could accurately recognize speech below - 20 dBSNR across delays., Conclusions: These results highlight the efficacy of wireless systems with HI adults. Speech-intelligibility benefits are affected by transmission delays only when the delay is greater than 40 ms and the coupling is vented.

Objectives: The current study was designed to see how hearing-impaired individuals judge level differences between speech sounds with and without hearing amplification. It was hypothesized that hearing aid compression should adversely affect the user's ability to judge level differences., Design: Thirty-eight hearing-impaired participants performed an adaptive tracking procedure to determine their level-discrimination thresholds for different word and sentence tokens, as well as speech-spectrum noise, with and without their hearing aids. Eight normal-hearing participants performed the same task for comparison., Results: Level discrimination for different word and sentence tokens was more difficult than the discrimination of stationary noises. Word level discrimination was significantly more difficult than sentence level discrimination. There were no significant differences, however, between mean performance with and without hearing aids and no correlations between performance and various hearing aid measurements., Conclusions: There is a clear difficulty in judging the level differences between words or sentences relative to differences between broadband noises, but this difficulty was found for both hearing-impaired and normal-hearing individuals and had no relation to hearing aid compression measures. The lack of a clear adverse effect of hearing aid compression on level discrimination is suggested to be due to the low effective compression ratios of currently fit hearing aids.

Rippled noises evoke the perception of pitch in human listeners. Infinitely iterated rippled noise (IIRN) is generated when wideband noise (WBN) is delayed, attenuated, and added to the original WBN through either a positive (+) or a negative (-) feedback loop. The pitch of IIRN[+] is matched to the reciprocal of the delay, whereas the pitch of IIRN[-] for the same delay is an octave lower. Chinchillas (Chinchilla laniger) were trained to discriminate IIRN[+] with a 4-ms delay from IIRN[+] with a 2-ms delay and then tested in a stimulus generalization paradigm with IIRN[+] at delays between 2 and 4 ms. Systematic gradients in behavioral response occurred along the dimension of delay, suggesting that a perceptual dimension corresponding to pitch exists for IIRN[+]. Behavioral responses to IIRN[-] test stimuli were more variable among chinchillas, suggesting that IIRN[-] did not evoke similar pitches relative to IIRN[+]. Systematic gradients in behavioral response were observed when IIRN[-] test stimuli were presented in the context of other IIRN[-] stimuli. Thus, other perceptual cues such as timbre may dominate the pitch cues when IIRN[-] test stimuli are presented in the context of IIRN[+] stimuli., (Copyright 2007 APA.)

Chinchillas were trained to discriminate a cosine-phase harmonic tone complex (COS) from wideband noise (WBN) and tested in a stimulus generalization paradigm with tone complexes in which phase differed between frequency regions. In this split-phase condition, responses to complexes made of random-phase low frequencies, cosine-phase high frequencies were similar to responses to the COS-training stimulus. However, responses to complexes made of cosine-phase low frequencies, random-phase high frequencies were generally lower than their responses to the COS-training stimulus. When tested with sine-phase (SIN) and random-phase (RND) tone complexes, responses were large for SIN, but were small for RND. Chinchillas were then trained to discriminate infinitely-iterated rippled noise (IIRN) from WBN and tested with noises in which the spectral ripple differed between frequency regions. In this split-spectrum condition, responses were large to noises made of rippled-spectrum low frequencies, flat-spectrum high frequencies, whereas responses were generally lower to noises made of flat-spectrum low frequencies, rippled-spectrum high frequencies. The results suggest that chinchillas listen across all frequencies, but attend to high frequencies when discriminating COS from WBN and attend to low frequencies when discriminating IIRN from WBN.

Behavioral responses obtained from chinchillas trained to discriminate a cosine-phase harmonic tone complex from wideband noise indicate that the perception of 'pitch' strength in chinchillas is largely influenced by periodicity information in the stimulus envelope. The perception of 'pitch' strength was examined in chinchillas in a stimulus generalization paradigm after animals had been retrained to discriminate infinitely iterated rippled noise from wideband noise. Retrained chinchillas gave larger behavioral responses to test stimuli having strong fine structure periodicity, but weak envelope periodicity. That is, chinchillas learn to use the information in the fine structure and consequently, their perception of 'pitch' strength is altered. Behavioral responses to rippled noises having similar periodicity strengths, but large spectral differences were also tested. Responses to these rippled noises were similar, suggesting a temporal analysis can be used to account for the behavior. Animals were then retested using the cosine-phase harmonic tone complex as the expected signal stimulus. Generalization gradients returned to those obtained originally in the naïve condition, suggesting that chinchillas do not remain "fine structure listeners," but rather revert back to being "envelope listeners" when the periodicity strength in the envelope of the expected stimulus is high.