Validation of a Self-Fitting Method for Over-the-Counter Hearing Aids.

In common practice, hearing aids are fitted by a clinician who measures an audiogram and uses it to generate prescriptive gain and output targets. This report describes an alternative method where users select their own signal processing parameters using an interface consisting of two wheels that optimally map to simultaneous control of gain and compression in each frequency band. The real-world performance of this approach was evaluated via a take-home field trial.

Listener Factors Explain Little Variability in Self-Adjusted Hearing Aid Gain.

Self-adjustment of hearing aid gain can provide valuable information about the gain preferences of individual listeners, but these preferences are not well understood. Listeners with mild-to-moderate hearing loss used self-adjustment to select amplification gain and compression parameters in real time on a portable touch screen device while listening in quiet and noisy backgrounds. Adjustments to gain prescribed by the National Acoustics Laboratories' non-linear fitting procedure (NAL-NL2) showed large between-subject variability.

Self-Adjusted Amplification Parameters Produce Large Between-Subject Variability and Preserve Speech Intelligibility.

The current study used the self-fitting algorithm to allow listeners to self-adjust hearing-aid gain or compression parameters to select gain for speech understanding in a variety of quiet and noise conditions. Thirty listeners with mild to moderate sensorineural hearing loss adjusted gain parameters in quiet and in several types of noise. Outcomes from self-adjusted gain and audiologist-fit gain indicated consistent within-subject performance but a great deal of between-subject variability.

Modeling the Influence of Acoustic Coupling of Hearing Aids on FM Signal-to-Noise Ratio.

Purpose: A model was developed to examine variables that influence signal-to-noise ratio (SNR) at the tympanic membrane (TM) when using a hearing aid (HA) and frequency modulated (FM) system. The model was used to explore how HA coupling influences SNR.

Method: To generate the model, HA output was measured in a coupler.

Reliability and accuracy of a method of adjustment for self-measurement of auditory thresholds.

Objective: To evaluate the reliability and accuracy of a method for measuring pure tone air conduction thresholds in which the user adjusts test tones to threshold, using an iPad, automated instructions, and minimal supervision.

Study Design: Prospective nonrandomized validation study.

Setting: University hearing research laboratories and audiology clinics.

Stuart Gatehouse: the international perspective.

The international contributions of Stuart Gatehouse are reviewed in three areas: as a scientist, as an advisor to health policy makers, and as a participant in international conferences. He was able, as no other auditory scientist of his time, to bridge the gap between scientific and clinical research. His ability to apply sound scientific principles to issues of clinical importance was most apparent in his work in three main areas of his research: acclimatization to amplified speech, auditory disability and hearing aid benefit, and candidature for linear and nonlinear signal processing.

SII and fit-to-target analysis of compression system performance as a function of number of compression channels.

This work was undertaken to answer the question, 'How does the speech audibility/fit-to-gain-target provided by compression change with number of channels?' For each of 957 audiograms and a given number of compression channels, the channel crossover frequencies were set either to maximize the SII (speech intelligibility index) for low- and high-level speech spectra, or to optimize the fit-to-gain targets from the Cambridge method for loudness equalization (CAMEQ). The audiograms comprised all common configurations, and losses ranged from mild to severe. Use of these computational procedures allowed the predicted, channel-number-based performance to be determined separately from the effects of other compression parameters.

Localization and speech-identification ability of hearing-impaired listeners using phase-preserving amplification.

Objective: The purpose of these experiments was to determine the ability of hearing-impaired listeners to localize and to identify speech in noise using phase-preserving and non-phase-preserving amplification.

Design: These abilities were measured 4 times over each of two 16-week periods, using a randomized, single-blinded, within-subject crossover design. Listeners were fitted bilaterally, using the National Acoustic Laboratories linear frequency-gain characteristic with a digital hearing aid programmed in one of two ways: (1) with a linear-phase filter and (2) with filters designed to compensate for the magnitude and phase anomalies caused by the hearing aid fitting, thus preserving interaural phase.

Hearing aid troubleshooting based on patients' descriptions.

Clinical audiologists were surveyed to determine the terms that their patients use to describe their reaction to hearing aid fitting problems. From this survey, a vocabulary of 40 frequently reported terms was developed. A second survey of hearing aid fitting experts was conducted to determine their methods of troubleshooting a hearing aid fitting when the patient reports one of the frequently reported terms.