Adaptive auditory brightness perception

Perception adapts to the properties of prior stimulation, as illustrated by phenomena such as visual color constancy or speech context effects. In the auditory domain, only little is known about adaptive processes when it comes to the attribute of auditory brightness. Here, we report an experiment that tests whether listeners adapt to spectral colorations imposed on naturalistic music and speech excerpts. Our results indicate consistent contrastive adaptation of auditory brightness judgments on a trial-by-trial basis. The pattern of results suggests that these effects tend to grow with an increase in the duration of the adaptor context but level off after around 8 trials of 2 s duration. A simple model of the response criterion yields a correlation of r = .97 with the measured data and corroborates the notion that brightness perception adapts on timescales that fall in the range of auditory short-term memory. Effects turn out to be similar for spectral filtering based on linear spectral filter slopes and filtering based on a measured transfer function from a commercially available hearing device. Overall, our findings demonstrate the adaptivity of auditory brightness perception under realistic acoustical conditions.

Connected Hearing Devices and Audiologists: The User-Centered Development of Digital Service Innovations

Today, medical technology manufacturers enter the service market through the development of digital service innovations. In the field of audiology, these developments increasingly shift the service capacities from audiologists to manufacturers and technical systems. However, the technology-driven developments of manufacturers lack acceptance of hearing device users and undermine the important role of audiologists within the service provision. By following a user-centered design approach in order to deal with the technological and social challenges of disruptive services, we aim to develop service innovations on an integrated service platform in the field of tele-audiology. To ensure the acceptance of technology-driven service innovations among hearing device users and audiologists, we systematically integrated these actors in a participatory innovation process. With qualitative and quantitative data we identified several requirements and preferences for different service innovations in the field of tele-audiology. According to the preferences of the different actors, we proposed a service platform approach based on a connected hearing device in three pillars of application: 1) one-to-one (1:1) service innovations based on a remote fitting concept directly improve the availability of services offered by audiologists without being physically present. Based on this, 2) one-to-many (1:N) service innovations allow the use of the connected hearing device as an indirect data source for training a machine learning algorithm that empowers users through the automation of service processes. A centralized server system collects the data and performs the training of this algorithm. The optimized algorithm is provided to the connected hearing devices to perform automatic acoustic scene classification. This in turn allows optimization of the hearing devices within each acoustic scene. After the user-centered development of the different service innovations which are designed to converge on an integrated service platform, we experimentally evaluated the functionality and applicability of the system as well as the associated role models between the technical system, the hearing device users and audiologists. As a future outlook, we show potentials to use the connected hearing device for 3) cross-industry (N:M) service innovations in contexts outside the healthcare domain and give practical implications for the market launch of successful service innovations in the field of tele-audiology.

Hearing Aid Consumer Reviews: A Linguistic Analysis in Relation to Benefit and Satisfaction Ratings

Purpose Online reviews have been used by hearing aid owners to share their experiences and to provide suggestions to potential hearing aid buyers, although they have not been systematically examined. The study was aimed at examining the hearing aid consumer reviews using automated linguistic analysis, and how the linguistic variables relate to self-reported hearing aid benefit and satisfaction ratings. Method The study used a cross-sectional design. One thousand three hundred seventy-eight consumer hearing aid reviews (i.e., text response to open-ended question), self-reported benefit and satisfaction ratings on hearing aids in a 5-point scale with meta-data (e.g., hearing aid brand, technology level) extracted from the Hearing Tracker website were analyzed using automated text analysis method known as the Linguistic Inquiry and Word Count. Results Self-reported hearing aid benefit and satisfaction ratings were high (i.e., mean rating of 4.04 in a 5-point scale). Examining the association between overall rating and the key linguistic variables point to two broad findings. First, the more people were personally, socially, and emotionally engaged with the hearing device experience, the higher they rated their hearing device(s). Second, a minimal occurrence of clinic-visit language dimensions points to factors that likely affect benefit and satisfaction ratings. For example, if people mention paying too much money (money), their overall ratings are generally lower. Conversely, if people write about their health or home, the ratings were higher. There was no significant difference in linguistic analysis across different hearing aid brands and technology levels. Conclusions Hearing aid consumers are generally satisfied with their hearing device(s), and their online reviews contain information about social/emotional dimensions as well as clinic-visit related aspects that have bearing toward hearing aid benefit and satisfaction ratings. These results suggest that the natural language used by consumers provide insights on their perceived benefit/satisfaction from their hearing device.

Implementation of a fully implantable middle-ear hearing device chip

BACKGROUND AND OBJECTIVE: Recently, with the increase in the population of hearing impaired people, various types of hearing aids have been rapidly developed. In particular, a fully implantable middle ear hearing device (F-IMEHD) is developed for people with sensorineural hearing loss. The F-IMEHD system comprises an implantable microphone, a transducer, and a signal processor. The signal processor should have a small size and consume less power for implantation in a human body. METHODS: In this study, we designed and fabricated a signal-processing chip using the modified FFT algorithm. This algorithm was developed focusing on eliminating time delay and system complexity in the transform process. The designed signal-processing chip comprises a 4-channel WDRC, a fitting memory, a communication 1control part, and a pulse density modulator. Each channel is separated using a 64-point fast Fourier transform (FFT) method and the gain value is matched using the fitting table in the fitting memory. RESULTS AND CONCLUSION: The chip was designed by Verilog-HDL and the designed HDL codes were verified by Modelsim-PE 10.3 (Mentor graphics, USA). The chip was fabricated using a 0.18 μm CMOS process (SMIC, China). Experiments were performed on a cadaver to verify the performance of the fabricated chip.

Cervicofacial surgery and implantable hearing device extrusion: management of challenging cases

ObjectiveTo describe our management of implantable hearing device extrusion in cases of previous cervicofacial surgery.MethodsA review was conducted of a retrospectively acquired database of surgical procedures for implantable hearing devices performed at our department between January 2011 and December 2019. Cases of device extrusion and previous cervicofacial surgery are included. Medical and surgical management is discussed.ResultsFour cases of implant extrusion following cervicofacial surgery were identified: one involving a Bonebridge system and three involving cochlear implants. In all cases, antibiotic treatment was administered and surgical debridement performed. The same Bonebridge system was implanted in the middle fossa. The three cochlear implants were removed, and new devices were implanted in a more posterior region.ConclusionPrevious cervicofacial surgery is a risk factor for hearing implant extrusion. The middle fossa approach is the best option for the Bonebridge system. Regarding the cochlear implant, it is always suitable to place it in a more posterior area. An inferiorly based fascio-muscular flap may be a good option to reduce the risk of extrusion.

Spatial Resolution of Late Reverberation in Virtual Acoustic Environments

Late reverberation involves the superposition of many sound reflections, approaching the properties of a diffuse sound field. Since the spatially resolved perception of individual late reflections is impossible, simplifications can potentially be made for modelling late reverberation in room acoustics simulations with reduced spatial resolution. Such simplifications are desired for interactive, real-time virtual acoustic environments with applications in hearing research and for the evaluation of hearing supportive devices. In this context, the number and spatial arrangement of loudspeakers used for playback additionally affect spatial resolution. The current study assessed the minimum number of spatially evenly distributed virtual late reverberation sources required to perceptually approximate spatially highly resolved isotropic and anisotropic late reverberation and to technically approximate a spherically isotropic sound field. The spatial resolution of the rendering was systematically reduced by using subsets of the loudspeakers of an 86-channel spherical loudspeaker array in an anechoic chamber, onto which virtual reverberation sources were mapped using vector base amplitude panning. It was tested whether listeners can distinguish lower spatial resolutions of reproduction of late reverberation from the highest achievable spatial resolution in different simulated rooms. The rendering of early reflections remained unchanged. The coherence of the sound field across a pair of microphones at ear and behind-the-ear hearing device distance was assessed to separate the effects of number of virtual sources and loudspeaker array geometry. Results show that between 12 and 24 reverberation sources are required for the rendering of late reverberation in virtual acoustic environments.

The Hearpiece database of individual transfer functions of an in-the-ear earpiece for hearing device research

We present a database of acoustic transfer functions of the Hearpiece, a commercially available multi-microphone multi-driver in-the-ear earpiece for hearing device research. The database includes HRTFs for 87 incidence directions as well as responses of the drivers, all measured at the four microphones of the Hearpiece as well as the eardrum in the occluded and open ear. The transfer functions were measured in both ears of 25 human participants and a KEMAR with anthropometric pinnae for five insertions of the device. We describe the measurements of the database and analyse derived acoustic parameters of the device. All regarded transfer functions are subject to differences between participants and insertions. Also, the KEMAR measurements are close to the median of human data in the present results for all assessed transfer functions. The database is a rich basis for development, evaluation and robustness analysis of multiple hearing device algorithms and applications. It is openly available at https://doi.org/10.5281/zenodo.3733190.