Hearing Research Research Articles

An Ideal-observer standard for evaluating relative cue reliance on multi-talker speech segregation

Modern hearing research identifies the ability of listeners to segregate simultaneous speech streams with a reliance on three major voice cues, fundamental frequency, level, and location. Few of these studies, however, present cues simultaneously as in natural listening, and fewer still consider the relative reliance listeners placed on these cues owing to the cues’ different units of measure. In the present study, trial-by-trial analyses were used to isolate listener reliance on the three voice cues presented simultaneously, with the behavior of an ideal observer (Green and Swets, 1966, pp. 151–178) serving as standard for determining their relative reliance. Listeners heard on each trial a pair of randomly selected, simultaneously recordings of naturally spoken sentences. One of the recordings was always from the same talker, a distracter, the other, with equal probability, was from one of two target talkers differing in the three voice cues. The listener’s task was to identify the target talker. Among 33 clinically normal-hearing adults only one relied predominantly on voice level, the remaining were split between voice fundamental frequency and location. The results are discussed regarding their implications for the common practice of using target-distracter level as a dependent measure of multi-talker speech segregation.

E-Babylab: An open-source browser-based tool for unmoderated online developmental studies.

The COVID-19 pandemic massively changed the context and feasibility of developmental research. This new reality, as well as considerations about sample diversity and naturalistic settings for developmental research, highlights the need for solutions for online studies. In this article, we present e-Babylab, an open-source browser-based tool for unmoderated online studies targeted for young children and babies. e-Babylab offers an intuitive graphical user interface for study creation and management of studies, users, participant data, and stimulus material, with no programming skills required. Various kinds of audiovisual media can be presented as stimuli, and possible measures include webcam recordings, audio recordings, key presses, mouse-click/touch coordinates, and reaction times. An additional feature of e-Babylab is the possibility to administer short adaptive versions of MacArthur-Bates Communicative Development Inventories (Chai et al. Journal of Speech, Language, and Hearing Research, 63, 3488-3500, 2020). Information pages, consent forms, and participant forms are customizable. e-Babylab has been used with a variety of measures and paradigms in over 12 studies with children aged 12 months to 8 years (n = 1516). We briefly summarize some results of these studies to demonstrate that data quality, participant engagement, and overall results are comparable between laboratory and online settings. Finally, we discuss helpful tips for using e-Babylab and present plans for upgrades.

Speech, Language, and Hearing in the 21st Century: A Bibliometric Review of JSLHR From 2001 to 2021.

A bibliometric analysis was performed for articles published in the Journal of Speech, Language, and Hearing Research (JSLHR) from 2001 to 2021 to examine changes to and emerging trends in the speech, language, and hearing sciences in the 21st century. Quantitative analyses using JASP were performed on the publication rate and number of authors in articles published in JSLHR for each year from 2001 to 2021. VOSviewer was used to analyze and visualize networks of co-occurring Keyword Plus terms extracted from the articles published in JSLHR for several representative years from 2001 to 2021. Although the number of publications and number of authors published in JSLHR increased from 2001 to 2021, that growth was consistent with the growth found in science in general and with changes in publication policies and practices. The number and range of countries other than the United States published in JSLHR increased from 2001 to 2021. A consistent set of institutions published frequently in JSLHR across the years examined. The analysis of Keyword Plus terms showed an increase in the range of populations, disorders, and languages that were the subject of research from 2001 to 2021, as well as influences from other fields on speech, language, and hearing sciences. The science of science approach and the tools of network science are useful for assessing how changes in editorial policy affect diversity, for monitoring research topics that are growing (or declining), for identifying institutions that lead the field, and for inviting discussions among various interested parties related to the growth and development of a discipline.

New horizons in hearing conditions.

Hearing conditions such as hearing loss, tinnitus and hyperacusis are highly prevalent in the population and can severely impact communication and quality of life. Hearing is affected by multiple factors, including heredity, noise exposure, age, sex, ear disorders and lifestyle factors. Globally, hearing loss affects over 80% of adults aged 80years and older, is often experienced in combination with other long-term health conditions and is a mid-life risk factor for dementia. To form a themed collection, we searched Age and Ageing for articles on hearing conditions published from 2000 onwards. This resulted in 22 articles included within the collection. They examined a range of important topics related to hearing healthcare and research, including noise-induced hearing loss, health service quality and safety, psychological and psychosocial consequences of hearing loss and co-morbidities of hearing loss. All articles reported on hearing loss; there were no published articles with a primary focus on other hearing conditions such as tinnitus or hyperacusis, on the health of older people from the Deaf community or on users of Cochlear implants, suggesting key gaps in knowledge and targets for future research. This New Horizons article highlights novel directions in research and practice and takes a forward look at how research into hearing conditions may develop in years to come. It highlights opportunities for the growth of patient-centred research and hearing healthcare supported by the better integration of health and care services as well as cross-speciality working to include common co-morbid health conditions.

Whole Neonatal Cochlear Explants as an In vitro Model.

Untreated hearing loss imposes significant costs on the global healthcare system and impairs individuals' quality of life. Sensorineural hearing loss is characterized by the cumulative and irreversible loss of sensory hair cells and auditory nerves in the cochlea. Entire and vital cochlear explants are one of the fundamental tools in hearing research to detect hair cell loss and to characterize the molecular mechanisms of the inner ear cells. Many years ago, a protocol for neonatal cochlear isolation was developed, and although it has been modified over time, it still holds potential for improvement. This paper presents an optimized protocol for isolating and culturing whole neonatal cochlear explants in multi-well culture chambers that enables the study of hair cells and spiral ganglion neuron cells along the entire length of the cochlea. The protocol was tested using cochlear explants from mice and rats. Healthy cochlear explants were obtained to study the interaction between hair cells, spiral ganglion neuron cells, and the surrounding supporting cells. One of the main advantages of this method is that it simplifies the organ culture steps without compromising the quality of the explants. All three turns of the organ of Corti are attached to the bottom of the chamber, which facilitates in vitro experiments and the comprehensive analysis of the explants. We provide some examples of cochlear images from different experiments with live and fixed explants, demonstrating that the explants retain their structure despite exposure to ototoxic drugs. This optimized protocol can be widely used for the integrative analysis of the mammalian cochlea.

VA Hearing, Tinnitus, and Balance Research that Leads to Better Patient Outcomes and Care

VA Hearing, Tinnitus, and Balance Research that Leads to Better Patient Outcomes and Care

Conditional Minimal Detectable Change for the Cochlear Implant Quality of Life-35 Profile Associated With Improved Functional Abilities 12 Months After Cochlear Implantation

It is essential to measure an individual patient's baseline and follow-up abilities to demonstrate changes in clinical outcomes over time. Inherent in this strategy is interpreting whether the measured change is clinically significant and beyond measurement error. Conditional minimal detectable change (cMDC) values are widely used in many disciplines but have rarely been established for outcome measures in otolaryngology or hearing research, and never in cochlear implantation. To determine cMDC values for the Cochlear Implant Quality of Life-35 (CIQOL-35) Profile instrument to enhance our understanding of the initial and ongoing changes in functional abilities from cochlear implants (CIs). Item response theory analyses of responses from a multi-institutional cohort of 705 CI users at a tertiary CI center were used to derive standard error (SE) values for each possible CIQOL-35 domain score. Using an iterative approach, these SE values were used to calculate cMDC values for every possible pre-CI and post-CI domain score combination. We then compared pre-CI to 12-month post-CI CIQOL-35 domains scores in an independent cohort of 65 adult CI users to determine whether the measured change exceeded error to be clinically significant. The analysis took place on December 14, 2022. The CIQOL-35 Profile instrument and cochlear implantation. The cMDC values were smaller for the communication domain, and global measure and cMDC values for all domains were larger at the extremes of the measurement scale. Overall, 60 CI users (92.3%) demonstrated improvement beyond cMDC at 12 months post-CI for at least 1 CIQOL-35 domain, and no patients' scores declined beyond cMDC for any domain. The percentage of CI users demonstrating improvement beyond cMDC varied by domain, with communication (53 [81.5%]) showing the largest number of CI users improving, followed by global (42 [64.6%]) and entertainment (40 [60.9%]). In general, CI users who demonstrated improvement in CIQOL-35 domains had greater improvement in speech recognition scores than patients who did not, but the strength and significance of these associations greatly varied by domain and speech material. This multistep cohort study found that cMDC values for the CIQOL-35 Profile provided personalized thresholds for detecting real changes in patient self-reported functional abilities over time across multiple domains, which may inform clinical decision-making. Moreover, these longitudinal results reveal the domains with more or less improvement, which may aid in patient counseling.

Barriers and facilitators to the inclusion of deaf people in clinical trials.

This article discusses the barriers that prevent deaf people from participating in clinical trials and offers recommendations to overcome these barriers and ensure equal access to study participation. Between April and May 2022, we conducted six focus groups with 20 deaf adults who use American Sign Language, all of whom had previous experience as research study participants. Focus group prompts queried community awareness of clinical trial opportunities, barriers and facilitators to deaf people's participation in clinical trials, and recommended resources to improve clinical trial access. This qualitative focus group data is supplemented by survey data gathered from 40 principal investigators and clinical research coordinators between November 2021 and December 2021. The survey queried researchers' prior experiences with enrolling deaf participants in clinical trials and strategies they endorse for enrollment of deaf participants in future clinical trials. Focus group participants unanimously agreed that, compared to the general hearing population, deaf sign language users lack equivalent access to clinical trial participation. Reported barriers included lack of awareness of clinical trial opportunities, mistrust of hearing researchers, and refusal by clinical trial staff to provide accessible communication (e.g. denial of requests for sign language interpreters). Survey data from 40 principal investigators and clinical research coordinators corroborated these barriers. For example, only 2 out of 40 survey respondents had ever enrolled a deaf person in a clinical trial. Respondents indicated that the most helpful strategies for including deaf sign language users in future clinical trials would be assistance with making recruitment information accessible to deaf sign language users and assistance in identifying qualified interpreters to hire to help facilitate the informed consent process. The lack of communication accessibility is the most common factor preventing deaf sign language users from participating in clinical trials. This article provides recommendations for hearing researchers to improve deaf people's access to clinical trials moving forward, drawing from mixed-methods data.

American Hearing Research Foundation research grants

Corporate Philanthropy ReportVolume 38, Issue 6 p. 16-16 Grant Alerts American Hearing Research Foundation research grants First published: 08 May 2023 https://doi.org/10.1002/cprt.31635Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. Volume38, Issue6June 2023Pages 16-16 RelatedInformation

Refinement of systemic guinea pig deafening in hearing research: Sensorineural hearing loss induced by co-administration of kanamycin and furosemide via the leg veins.

Auditory disabilities have a large impact on the human population worldwide. Research into understanding and treating hearing disabilities has increased significantly in recent years. One of the most relevant animal species in this context is the guinea pig, which has to be deafened to study several of the hearing pathologies and develop novel therapies. Applying kanamycin subcutaneously and furosemide intravenously is a long-established method in hearing research, leading to permanent hearing loss without surgical intervention at the ear. The intravenous application of furosemide requires invasive surgery in the cervical area of the animals to expose the jugular vein, since a relatively large volume (1 ml per 500 g body weight) must be injected over a period of about 2.5 min. We have established a gentler alternative by applying the furosemide by puncture of the leg veins. For this, custom-made cannula-needle devices were built to allow the vein puncture and subsequent slow injection of the furosemide. This approach was tested in 11 guinea pigs through the foreleg via the cephalic antebrachial vein and through the hind leg via the saphenous vein. Frequency-specific hearing thresholds were measured before and after the procedure to verify normal hearing and successful deafening, respectively. The novel approach of systemic deafening was successfully implemented in 10 out of 11 animals. The Vena saphena was best suited to the application. Since the animals' condition, post leg vein application, was better in comparison to animals deafened by exposure of the Vena jugularis, the postulated refinement that reduced animal stress was deemed successful.

A Review of Virtual Reality for Individuals with Hearing Impairments

Virtual Reality (VR) technologies have the potential to be applied in a clinical context to improve training and rehabilitation for individuals with hearing impairment. The introduction of such technologies in clinical audiology is in its infancy and requires devices that can be taken out of laboratory settings as well as a solid collaboration between researchers and clinicians. In this paper, we discuss the state of the art of VR in audiology with applications to measurement and monitoring of hearing loss, rehabilitation, and training, as well as the development of assistive technologies. We review papers that utilize VR delivered through a head-mounted display (HMD) and used individuals with hearing impairment as test subjects, or presented solutions targeted at individuals with hearing impairments, discussing their goals and results, and analyzing how VR can be a useful tool in hearing research. The review shows the potential of VR in testing and training individuals with hearing impairment, as well as the need for more research and applications in this domain.

Community Perspectives on Hearing Loss in Rural Alaska.

The aim of this study is to present an explanatory model of hearing loss in the Bering Strait region of Alaska in order to contextualize the results of a cluster randomized trial and propose implications for regional hearing-related health care. To promote ecological validity, or the generalizability of trial findings to real world experiences, qualitative methods (focus groups and interviews) were used within a mixed methods cluster randomized trial evaluating school hearing screening and follow-up processes in 15 communities in the Bering Strait region of Alaska. Focus groups were held between April and August 2017, and semistructured interviews were conducted between December 2018 and August 2019. Convenience sampling was used for six of the 11 focus groups to capture broad community feedback. Purposive sampling was used for the remaining five focus groups and for all interviews to capture a variety of experiences with hearing loss. Audio recordings of focus groups and interviews were transcribed, and both notes and transcripts were deidentified. All notes and transcripts were included in the analysis. The constant comparative method was used to develop a codebook by iteratively moving between transcripts and preliminary themes. Researchers then used this codebook to code data from all focus groups and interviews using qualitative analysis software (NVIVO 12, QSR International) and conducted thematic analyses to distill the findings presented in this article. Participants in focus groups (n = 116) and interviews (n = 101) shared perspectives in three domains: etiology, impact, and treatment of hearing loss. Regarding etiology, participants emphasized noise-induced hearing loss but also discussed infection-related hearing loss and various causes of ear infections. Participants described the impact of hearing loss on subsistence activities, while also detailing social, academic, and economic consequences. Participants described burdensome treatment pathways that are repetitive and often travel and time intensive. Communication breakdowns within these pathways were also described. Some participants spoke positively of increased access via onsite hearing health care services in "field clinics" as well as via telemedicine services. Others described weaknesses in these processes (infrequent field clinics and communication delays in telemedicine care pathways). Participants also described home remedies and stigma surrounding the treatment for hearing loss. Patient-centered health care requires an understanding of context. Explanatory models of illness are context-specific ways in which patients and their networks perceive and describe the experience of an illness or disability. In this study, we documented explanatory models of hearing loss to foster ecological validity and better understand the relevance of research findings to real-life hearing-related experiences. These findings suggest several areas that should be addressed in future implementation of hearing health care interventions elsewhere in rural Alaska, including management of repetitious treatments, awareness of infection-mediated hearing loss, mistrust, and communication breakdowns. For hearing-related health care in this region, these findings suggest localized recommendations for approaches for prevention and treatment. For community-based hearing research, this study offers an example of how qualitative methods can be used to generate ecologically valid (i.e., contextually grounded) findings.

Species-Specific Adaptation for Ongoing High-Frequency Action Potential Generation in MNTB Neurons.

Comparative analysis of evolutionarily conserved neuronal circuits between phylogenetically distant mammals highlights the relevant mechanisms and specific adaptations to information processing. The medial nucleus of the trapezoid body (MNTB) is a conserved mammalian auditory brainstem nucleus relevant for temporal processing. While MNTB neurons have been extensively investigated, a comparative analysis of phylogenetically distant mammals and the spike generation is missing. To understand the suprathreshold precision and firing rate, we examined the membrane, voltage-gated ion channel and synaptic properties in Phyllostomus discolor (bat) and in Meriones unguiculatus (rodent) of either sex. Between the two species, the membrane properties of MNTB neurons were similar at rest with only minor differences, while larger dendrotoxin (DTX)-sensitive potassium currents were found in gerbils. Calyx of Held-mediated EPSCs were smaller and frequency dependence of short-term plasticity (STP) less pronounced in bats. Simulating synaptic train stimulations in dynamic clamp revealed that MNTB neurons fired with decreasing success rate near conductance threshold and at increasing stimulation frequency. Driven by STP-dependent conductance decrease, the latency of evoked action potentials increased during train stimulations. The spike generator showed a temporal adaptation at the beginning of train stimulations that can be explained by sodium current inactivation. Compared with gerbils, the spike generator of bats sustained higher frequency input-output functions and upheld the same temporal precision. Our data mechanistically support that MNTB input-output functions in bats are suited to sustain precise high-frequency rates, while for gerbils, temporal precision appears more relevant and an adaptation to high output-rates can be spared.SIGNIFICANCE STATEMENT Neurons in the mammalian medial nucleus of the trapezoid body (MNTB) convey precise, faithful inhibition vital for binaural hearing and gap detection. The MNTB's structure and function appear evolutionarily well conserved. We compared the cellular physiology of MNTB neurons in bat and gerbil. Because of their adaptations to echolocation or low frequency hearing both species are model systems for hearing research, yet with largely overlapping hearing ranges. We find that bat neurons sustain information transfer with higher ongoing rates and precision based on synaptic and biophysical differences in comparison to gerbils. Thus, even in evolutionarily conserved circuits species-specific adaptations prevail, highlighting the importance for comparative research to differentiate general circuit functions and their specific adaptations.

Clinical research in acoustics: Reflections on a journey from bench to bedside and back again

Thirty years ago, the author entered the field of acoustical research, curious as to how the human mind processes music. That search quickly led to the field of psychoacoustics and explorations of how basic sound elements are processed, which was presented at an ASA meeting in 1996. In 1999, the author had a benign tumor removed from his auditory nerve, leaving him deaf in his right ear. Over the next few years this led to his increasing interest in how people with altered hearing process sound. This presentation will describe the journey into clinical research that resulted, the amazing collaborative community that exists in hearing research, both on the clinical and basic sides, and how important it is to form connections among researchers and clinicians in order to fully explore the questions of how humans understand sound.

Modified Experimental Conditions for Noise-Induced Hearing Loss in Mice and Assessment of Hearing Function and Outer Hair Cell Damage.

An animal model of noise-induced hearing loss (NIHL) is useful for pathologists, therapists, pharmacologists, and hearing researchers to thoroughly understand the mechanism of NIHL, and subsequently optimize the corresponding treatment strategies. This study aims to create an improved protocol for developing a mouse model of NIHL. Male C57BL/6J mice were used in this study. Unanesthetized mice were exposed to loud noises (1 and 6 kHz, presented simultaneously at 115-125 dB SPL-A) continuously for 6 h per day for 5 consecutive days. Auditory function was assessed 1 day and 1 week after noise exposure, using auditory brainstem response (ABR). After the ABR measurement, the mice were sacrificed, and their organs of Corti were collected for immunofluorescence staining. From the auditory brainstem response (ABR) measurements, significant hearing loss was observed 1 day after noise exposure. After 1 week, the hearing thresholds of the experimental mice decreased to ~80 dB SPL, which was still a significantly higher level than the control mice (~40 dB SPL). From the results of immunofluorescence imaging, outer hair cells (OHCs) were shown to be damaged. In summary, we created a model of NIHL using male C57BL/6J mice. A new and simple device for generating and delivering pure-tone noise was developed and then employed. Quantitative measurements of hearing thresholds and morphological confirmation of OHC damage both demonstrated that the applied noise successfully induced an expected hearing loss.

Spatial audio for interactive hearing research

The use of sound field synthesis for hearing research has gained popularity due to the ability to auralize a wide range of sound scenes in a controlled and reproducible way. We are interested in reproducing acoustic environments for interactive hearing research, allowing participants to move freely over an extended area in the reproduced sound field. While the physically accurate sound field reproduction using sound field synthesis is limited to the sweet spot, it is unclear how different perceptual measures vary across the reproduction area and how suitable sound field synthesis is to evaluate them. To investigate the viability of listening experiments and provide a database for modelling approaches, measurements of binaural cues were carried out in the Simulated Open Field Environment loudspeaker array. Results show that the binaural cues are reproduced well close to the center, but exhibit more variance than in the corresponding free field case. Off center, lower interaural coherence is observed, which can affect binaural unmasking and speech intelligibility. In this work, we study binaural cues and speech reception thresholds over a wide area in the loudspeaker array to investigate the feasibility of psychoacoustic experiments involving speech understanding.

Building on the Academic Legacy of Pat Stelmachowicz and other Pioneers in Developmental Psychoacoustics and Pediatric Audiology: The Children's English/Spanish Speech Recognition Test (ChEgSS).

Basic research investigating auditory development often has implications for clinical diagnosis and treatment of hearing loss in children, but it can be challenging to translate those findings into practice. Meeting that challenge was a guiding principle of Pat Stelmachowicz's research and mentorship. Her example inspired many of us to pursue translational research and motivated the recent development of the Children's English/Spanish Speech Recognition Test (ChEgSS). This test evaluates word recognition in noise or two-talker speech, with target and masker speech produced in either English or Spanish. The test uses recorded materials and a forced-choice response, so the tester need not be fluent in the test language. ChEgSS provides a clinical measure of masked speech recognition outcomes for children who speak English, Spanish, or both, including estimates of performance in noise and two-talker speech, with the goal of maximizing speech and hearing outcomes for children with hearing loss. This article highlights several of Pat's many contributions to pediatric hearing research and describes the motivation and development of ChEgSS.

Resisting Ableism in School-Based Speech-Language Therapy: An Invitation to Change.

Resisting Ableism in School-Based Speech-Language Therapy: An Invitation to Change.

Pitch and tone: Primacy of production criteria in auditory perception

The brain performs diverse and complex operations effortlessly. Its sensitivity to minute stimulus changes, and precision in scaling sensory magnitudes, are yet to be understood by humans. Nevertheless, its limitless vault is accessible only if scientists can discipline themselves to abide by the laws of their science. There exist well-established psychophysical principles for dealing with sensory, mental, and all intangible phenomena. However, in hearing research, the generation of law-abiding scientists are long gone; the current generation of computer-oriented scientists hope to resolve all problems through random and effortless computations of endless varieties of meaningless variables without the concept of invariance. The case in point is hearing research; we are still searching for pitch (or tone) after 2,500 years of intensive inquiry. The failure augurs the existence of fundamental errors in the science. This paper describes a search for the origin of pitch which plays lexical and intonational roles in Yoruba, a tone language. The approach is based on the ecological conception of sound, with experimental evidence from speech surrogates (drums) and strings, guided by the concept of invariance. The investigations attain the conclusion that the brain does not perform any computations at all in pitch and tone perception, neither in music nor in speech. Rather, the data show that the brain measures a unique mechanical parameter of the sound source to which all physical and mechanical transformations lead. In every pitch/tone perception context, therefore, the brain discards all other factors which convey other attributes of sound outside pitch and tone. This finding accounts for constancy in auditory code perception despite overwhelming variability at the production and acoustic levels. Implications for all aspects of auditory perception research and neurophysiological investigations into brain mechanisms are discussed.

Linking Affective and Hearing Sciences-Affective Audiology.

A growing number of health-related sciences, including audiology, have increasingly recognized the importance of affective phenomena. However, in audiology, affective phenomena are mostly studied as a consequence of hearing status. This review first addresses anatomical and functional bidirectional connections between auditory and affective systems that support a reciprocal affect-hearing relationship. We then postulate, by focusing on four practical examples (hearing public campaigns, hearing intervention uptake, thorough hearing evaluation, and tinnitus), that some important challenges in audiology are likely affect-related and that potential solutions could be developed by inspiration from affective science advances. We continue by introducing useful resources from affective science that could help audiology professionals learn about the wide range of affective constructs and integrate them into hearing research and clinical practice in structured and applicable ways. Six important considerations for good quality affective audiology research are summarized. We conclude that it is worthwhile and feasible to explore the explanatory power of emotions, feelings, motivations, attitudes, moods, and other affective processes in depth when trying to understand and predict how people with hearing difficulties perceive, react, and adapt to their environment.