The aim of this study was to investigate changes in central auditory processing following unilateral and bilateral hearing aid fitting using a combination of physiological and behavioral measures: late auditory event-related potentials (ERPs) and speech recognition in noise, respectively. The hypothesis was that for fitted ears, the ERP amplitude would increase over time following hearing aid f...

This paper is mainly aimed at developing an advanced communication aid for the people having severe speech impairment. This method gives rise to a new form of communication aid which recognizes the disordered speech of the user and builds messages which are converted into synthetic speech. While employing this method, the recognition perplexity can be increased. The selected message building te...

This investigation measured the degree to which hearing aids degrade speech discrimination in noise. Ten normal-hearing subjects were tested for speech reception thresholds (SRT) in noise. The tests were repeated under two aided conditions: one used binaural behind-the-ear (BTE) aids, the other an experimental binaural high-fidelity aid fitted with in-the-ear transducers. To assess the loss of ...

OBJECTIVE To investigate speech stimuli and background-noise-dependent changes in cortical auditory-evoked potentials (CAEPs) in unaided and aided conditions, and determine amplification effects on CAEPs. DESIGN CAEPs to naturally produced syllables in quiet and in multi-talker babble were recorded, with and without a hearing aid in the right ear. At least 300 artifact-free trials for each pa...

The purpose of this study was to assess the relationship between the directivity of a directional microphone hearing aid and listener performance. Hearing aids were fit bilaterally to 19 subjects with sensorineural hearing loss, and five microphone conditions were assessed: omnidirectional, cardioid, hypercardioid, supercardioid, and "monofit," wherein the left hearing aid was set to omnidirect...

High-performance hearing aids require flat insertion gain (before processing) and low distortion, so that when signal processing is introduced the pre-processed response of the aid does not bias the processing. High-performance hearing aids need to process the signal to compensate for the patient's perceptive distortions (primarily accentuated high-frequency hearing loss and recruitment), and t...

OBJECTIVE To evaluate the improvement in speech intelligibility in noise obtained with an assistive real-time fixed endfire array of bidirectional microphones in comparison with an omnidirectional hearing aid microphone in a realistic environment. DESIGN The microphone array was evaluated physically in anechoic and reverberant conditions. Perceptual tests of speech intelligibility in noise we...

A visual speech training aid for persons with hearing impairments has been developed using a Windows-based multimedia computer. The training aid provides real time visual feedback as to the quality of pronunciation for 10 steady-state American English monopthong vowel phonemes (/aa/, /iy/, /uw/, /ae/, /er/, /ih/, /eh/, /ao/, /ah/, and /uh/). This training aid is thus referred to as a Vowel Arti...

Purpose: The study evaluated factors that influence the effectiveness of noise reduction (NR) algorithm in hearing aids, through acoustical measures. Methods: Factorial design was employed. Study sample: The output from hearing aid, with and without NR at three signal-to-noise ratios (SNR) with five types of noise, was recorded. The effect of noise reduction was studied through objective measur...