This paper summarizes twenty studies, published since 1989, that have measured experimentally the relationship between speech recognition in noise and some aspect of cognition, using statistical techniques such as correlation or factor analysis. The results demonstrate that there is a link, but it is secondary to the predictive effects of hearing loss, and it is somewhat mixed across study. No one cognitive test always gave a significant result, but measures of working memory (especially reading span) were mostly effective, whereas measures of general ability, such as IQ, were mostly ineffective. Some of the studies included aided listening, and two reported the benefits from aided listening: again mixed results were found, and in some circumstances cognition was a useful predictor of hearing-aid benefit.

Are individual differences in speech reception related to individual differences in cognitive ability? A survey of twenty experimental studies with normal and hearing-impaired adults

Intelligibility listening tests are necessary during development and evaluation of speech processing algorithms, despite the fact that they are expensive and time consuming. In this paper, we propose a monaural intelligibility prediction algorithm, which has the potential of replacing some of these listening tests. The proposed algorithm shows similarities to the short-time objective intelligibility STOI algorithm, but works for a larger range of input signals. In contrast to STOI, extended STOI ESTOI does not assume mutual independence between frequency bands. ESTOI also incorporates spectral correlation by comparing complete 400ms length spectrograms of the noisy/processed speech and the clean speech signals. As a consequence, ESTOI is also able to accurately predict the intelligibility of speech contaminated by temporally highly modulated noise sources in addition to noisy signals processed with time-frequency weighting. We show that ESTOI can be interpreted in terms of an orthogonal decomposition of short-time spectrograms into intelligibility subspaces, i.e., a ranking of spectrogram features according to their importance to intelligibility. A free MATLAB implementation of the algorithm is available for noncommercial use at http://kom.aau.dk/~jje/.

An Algorithm for Predicting the Intelligibility of Speech Masked by Modulated Noise Maskers

For analysing the processing of speech by a hearing instrument, a standard test signal is necessary which allows for reproducible measurement conditions, and which features as many of the m...

Development and analysis of an International Speech Test Signal (ISTS)

An at least partially implantable system for rehabilitation of a hearing disorder with at least one acoustic sensor (microphone) for picking up an acoustic sensor signal and converting the acoustic sensor signal into corresponding electrical signals, an electronic signal processing unit for audio signal processing and amplification, an electrical power supply unit which supplies individual components of the system with energy, and an output-side actuator stimulation arrangement, the actuator stimulation arrangement has a dual intracochlear arrangement in combination with a stimulator arrangement with at least one stimulator element for at least indirect mechanical stimulation of a damaged inner ear and one electrically acting stimulation electrode arrangement with at least one cochlear implant electrode for electrical stimulation of the inner ear.

At least partially implantable system for rehabilitation of a hearing disorder

A hearing aid includes a transceiver for interconnection of the hearing aid with a wireless network, and a communication controller that is adapted for controlling data exchange through the network in accordance with a network protocol, wherein the controller is further adapted for initialisation of the network in an acquisition mode by controlling the transceiver to transmit interrogation data repetitively, and upon receipt of an interrogation data received message from another device, in a connected mode acting as a master of the network by repetitively transmitting synchronization data at intervals that are longer than the intervals between transmitted interrogation data in the acquisition mode.

Hearing aid wireless network

Current standards involving technical specification of hearing aids provide limited possibilities for assessing the influence of the spectral and temporal characteristics of the input signal, and these characteristics have a significant effect on the output signal of many recent types of hearing aids. This is particularly true of digital hearing instruments, which typically include non-linear amplification in multiple channels. Furthermore, these instruments often incorporate additional non-linear functions such as “noise reduction” and “feedback cancellation”. The output signal produced by a non-linear hearing instrument relates to the characteristics of the input signal in a complex manner. Therefore, the choice of input signal significantly influences the outcome of any acoustic or psychophysical assessment of a non-linear hearing instrument. For this reason, the International Collegium for Rehabilitative Audiology (ICRA) has introduced a collection of noise signals that can be used for hearing aid tes...

ICRA Noises: Artificial Noise Signals with Speech-like Spectral and Temporal Properties for Hearing Instrument Assessment: Ruidos ICRA: Señates de ruido artificial con espectro similar al habla y propiedades temporales para pruebas de instrumentos auditivos

A binaural digital hearing aid system comprises two hearing aid units (1, 2) for arrangement in a user's left and right ear, respectively. Each unit comprises input signal transducer means (3r, 3l), A/D conversion means (4r, 4l), digital signal processing means (5r-13r, 5l-13l), D/A conversion means (14r, 14l) and output signal transducer means (15r, 15l). A bi-directional communication link (7) is provided between the units. The digital signal processing means of each unit is arranged to affect a substantially full digital signal processing including individual processing of signals from the input transducer means of the actual unit and simulated processing of signals from the input transducer means of the other unit as well as binaural signal processing and includes at least a first digital signal processor part (5r, 5l) for processing said internally supplied signal, a second digital signal processor part (6l, 6r) for processing the signal supplied via said communication link (7) and a third digital signal processor part (9r, 9l) to effect common binaural digital signal processing of information derived from the signals processed in said first and second digital signal processor parts, said second digital signal processor part (6l, 6r) in each unit simulating the first digital signal processor part (5l, 5r) in the other unit with respect to adjustment parameters controlling the performance of said first signal processor part in said other unit.

A binaural digital hearing aid system

In a remotely controllable, especially remote-control-programmable hearing aid with an external control device (1) with a keyboard (2), display device (3) and a data processing device (4) and also a hearing aid (9) controllable by the control device (1), in the control device there is a signal generator (11) actuatable and controllable via the keyboard (2) and the data processing device (4). This generator is releasably connected by a cable (12, 13, 14) to the hearing aid so that the control device (1) can be used together with the hearing aid to determine the hearing curve or, in general, the audiometric values of the wearer of the hearing aid in real conditions.

Remotely controlled, especially remotely programmable hearing aid system

An in-the-ear hearing aid comprises a plug (1) for arrangement in the ear channel and having a shell-like wall facing the interior of the ear channel and an exterior faceplate (2) which together define a generally closed cavity (3), in which the individual components of the hearing aid are arranged. An acoustical link in th form of a hose or tube piece (13) is provided between an orifice (14) at the external side of the part of the wall of the plug (1) facing the interior of the ear channel and the residual volume (12) of the internal cavity of the plug (1) and forms together with said residual volume (12) an approximated acoustical circuit having a resonance frequency in the region of the first voice sound formants of the user. Thereby a significantly reduces occlusion effect can be obtained in a simple way in a completed hearing aid.

In-the-ear hearing aid with reduced occlusion effect and method for the production and user-fitting of such a hearing aid

The application relates to an in-situ method to measure and correct or adjust the sound signal presented to the eardrum by means of a hearing aid and a hearing aid employing such a method. The hearing aid comprises at least one microphone (1), at least one digital signal processor (2) for transforming the microphone signal into a transformed signal according to a desired transformation function, a receiver (3), a sensing means (4) for sensing the sound signal appearing in front of the eardrum and at least one comparison means (5). A model of the electroacoustic system of the ear and the hearing aid is established and stored in the hearing aid, which model simulates the sound signal in the earcanal in front of the eardrum. This model is adapted in response of an error signal generated in case the difference between the representation of the sensed signal and the simulated sound signal is above a predetermined threshold.

Method for in-situ measuring and correcting or adjusting the output signal of a hearing aid with a model processor and hearing aid employing such a method

Soren Erik Westermann

Papers

ICRA Noises: Artificial Noise Signals with Speech-like Spectral and Temporal Properties for Hearing Instrument Assessment: Ruidos ICRA: Señates de ruido artificial con espectro similar al habla y propiedades temporales para pruebas de instrumentos auditivos

A binaural digital hearing aid system

Remotely controlled, especially remotely programmable hearing aid system

In-the-ear hearing aid with reduced occlusion effect and method for the production and user-fitting of such a hearing aid

Method for in-situ measuring and correcting or adjusting the output signal of a hearing aid with a model processor and hearing aid employing such a method