The effect of hearing aid microphone mode on performance in an auditory orienting task.

Objectives: Although directional microphones on a hearing aid provide a signal-to-noise ratio benefit in a noisy background, the amount of benefit is dependent on how close the signal of interest is to the front of the user. It is assumed that when the signal of interest is off-axis, users can reorient themselves to the signal to make use of the directional microphones to improve signal-to-noise ratio. The present study tested this assumption by measuring the head-orienting behavior of bilaterally fit hearing-impaired individuals with their microphones set to omnidirectional and directional modes.

A factor analysis of the SSQ (Speech, Spatial, and Qualities of Hearing Scale).

Objective: The speech, spatial, and qualities of hearing questionnaire (SSQ) is a self-report test of auditory disability. The 49 items ask how well a listener would do in many complex listening situations illustrative of real life. The scores on the items are often combined into the three main sections or into 10 pragmatic subscales.

Recording and analysis of head movements, interaural level and time differences in rooms and real-world listening scenarios.

The science of how we use interaural differences to localise sounds has been studied for over a century and in many ways is well understood. But in many of these psychophysical experiments listeners are required to keep their head still, as head movements cause changes in interaural level and time differences (ILD and ITD respectively). But a fixed head is unrealistic.

The contribution of head movement to the externalization and internalization of sounds.

Background: When stimuli are presented over headphones, they are typically perceived as internalized; i.e., they appear to emanate from inside the head.

The sensitivity of hearing-impaired adults to acoustic attributes in simulated rooms.

In previous studies we have shown that older hearing-impaired individuals are relatively insensitive to changes in the apparent width of broadband noises when those width changes were based on differences in interaural coherence [W. Whitmer, B. Seeber and M.

The effect of experience on the sensitivity and specificity of the whispered voice test: a diagnostic accuracy study.

Objectives: To determine the sensitivity and specificity of the whispered voice test (WVT) in detecting hearing loss when administered by practitioners with different levels of experience.

Design: Diagnostic accuracy study of WVT, through acoustic analysis of whispers of experienced and inexperienced practitioners (experiment 1) and behavioural validation of these recordings (experiment 2).

Setting: Research institute with a pool of patients sourced from local clinics in the Greater Glasgow area.

The internal representation of vowel spectra investigated using behavioral response-triggered averaging.

Listeners presented with noise were asked to press a key whenever they heard the vowels [a] or [i:]. The noise had a random spectrum, with levels in 60 frequency bins changing every 0.5 s.

The role of head movements and signal spectrum in an auditory front/back illusion.

We used a dynamic auditory spatial illusion to investigate the role of self-motion and acoustics in shaping our spatial percept of the environment. Using motion capture, we smoothly moved a sound source around listeners as a function of their own head movements. A lowpass filtered sound behind a listener that moved in the direction it would have moved if it had been located in the front was perceived as statically located in front.

Health-related quality of life before and after management in adults referred to otolaryngology: a prospective national study.

Objective: An assessment of the effect of otolaryngological management on the health-related quality of life of patients.

Design: Application of the Health Utilities Index mark 3 (HUI-3) before and after treatment; application of the Glasgow Benefit Inventory (GBI) after treatment.

Setting: Six otolaryngological departments around Scotland.

Undirected head movements of listeners with asymmetrical hearing impairment during a speech-in-noise task.

It has long been understood that the level of a sound at the ear is dependent on head orientation, but the way in which listeners move their heads during listening has remained largely unstudied. Given the task of understanding a speech signal in the presence of a simultaneous noise, listeners could potentially use head orientation to either maximize the level of the signal in their better ear, or to maximize the signal-to-noise ratio in their better ear. To establish what head orientation strategy listeners use in a speech comprehension task, we used an infrared motion-tracking system to measure the head movements of 36 listeners with large (>16 dB) differences in hearing threshold between their left and right ears.

The speech intelligibility benefit of a unilateral wireless system for hearing-impaired adults.

Objective: This study measured the effects of two previously untested practical considerations-venting and transmission delays-on speech intelligibility in a simulated unilateral wireless system, where a target signal in background noise was transmitted wirelessly to the hearing-impaired (HI) listener.

Design: Speech reception thresholds (SRTs) relative to the signal-to-noise ratio (SNR) were measured by varying the surrounding babble noise level. The target signal was presented at 0° azimuth in the soundfield and unilaterally via an insert earphone, using open and closed fittings with simulated-wireless delays ranging between 0-160 ms.

The effect of hearing impairment on localization dominance for single-word stimuli.

Localization dominance (one of the phenomena of the "precedence effect") was measured in a large number of normal-hearing and hearing-impaired individuals and related to self-reported difficulties in everyday listening. The stimuli (single words) were made-up of a "lead" followed 4 ms later by a equal-level "lag" from a different direction. The stimuli were presented from a circular ring of loudspeakers, either in quiet or in a background of spatially diffuse babble.

Level discrimination of speech sounds by hearing-impaired individuals with and without hearing amplification.

Objectives: The current study was designed to see how hearing-impaired individuals judge level differences between speech sounds with and without hearing amplification. It was hypothesized that hearing aid compression should adversely affect the user's ability to judge level differences.

Design: Thirty-eight hearing-impaired participants performed an adaptive tracking procedure to determine their level-discrimination thresholds for different word and sentence tokens, as well as speech-spectrum noise, with and without their hearing aids.

Grommets (ventilation tubes) for hearing loss associated with otitis media with effusion in children.

Background: Otitis media with effusion (OME; 'glue ear') is common in childhood and surgical treatment with grommets (ventilation tubes) is widespread but controversial.

Objectives: To assess the effectiveness of grommet insertion compared with myringotomy or non-surgical treatment in children with OME.

Search Strategy: We searched the Cochrane ENT Disorders Group Trials Register, other electronic databases and additional sources for published and unpublished trials (most recent search: 22 March 2010).

Informational masking in young and elderly listeners for speech masked by simultaneous speech and noise.

Three experiments measured the effects of age on informational masking of speech by competing speech. The experiments were designed to minimize the energetic contributions of the competing speech so that informational masking could be measured with no large corrections for energetic masking. Experiment 1 used a "speech-in-speech-in-noise" design, in which the competing speech was presented in noise at a signal-to-noise ratio (SNR) of -4 dB.

The detection of differences in the cues to distance by elderly hearing-impaired listeners.

This experiment measured the capability of hearing-impaired individuals to discriminate differences in the cues to the distance of spoken sentences. The stimuli were generated synthetically, using a room-image procedure to calculate the direct sound and first 74 reflections for a source placed in a 7 x 9 m room, and then presenting each of those sounds individually through a circular array of 24 loudspeakers. Seventy-seven listeners participated, aged 22-83 years and with hearing levels from -5 to 59 dB HL.

The binaural performance of a cross-talk cancellation system with matched or mismatched setup and playback acoustics.

Cross-talk cancellation is a method for synthesizing virtual auditory space using loudspeakers. One implementation is the "Optimal Source Distribution" technique [T. Takeuchi and P.

The psychoacoustics of binaural hearing.

This paper introduces the major phenomena of binaural hearing. The sounds arriving at the two ears are rarely the same: usually one ear will be partially shadowed from the sound source by the head, and the sound will also have to travel further to get to that ear. The resulting differences in interaural level and time can be detected by the auditory system and can be used to determine the direction of the source of sound.

Can dichotic pitches form two streams?

The phenomenon of auditory streaming reflects the perceptual organization of sounds over time. A series of "A" and "B" tones, presented in a repeating "ABA-ABA" sequence, may be perceived as one "galloping" stream or as two separate streams, depending on the presentation rate and the A-B frequency separation. The present experiment examined whether streaming occurs for sequences of "Huggins pitches," for which the percepts of pitch are derived from the binaural processing of a sharp transition in interaural phase in an otherwise diotic noise.

A self-report outcome measure for the evaluation of hearing aid fittings and services.

Objective: To design, optimise and validate an outcome measure for the evaluation of adult hearing aid fittings.

Design: A multi-dimensional subject-specific and situation-specific questionnaire (the Glasgow Hearing Aid Benefit Profile--GHABP) to assess initial disability, handicap, use, benefit, residual disability and satisfaction before and after hearing aid provision.

Subjects: Hearing-impaired adults attending National Health Service clinics for the first time for whom amplification is an appropriate management option.

Sound localization in noise in hearing-impaired listeners.

The present study assesses the ability of four listeners with high-frequency, bilateral symmetrical sensorineural hearing loss to localize and detect a broadband click train in the frontal-horizontal plane, in quiet and in the presence of a white noise. The speaker array and stimuli are identical to those described by Lorenzi et al. (in press).

Speech tests as measures of outcome.

Speech tests comprise an important and integral part of any assessment of the effectiveness of intervention for hearing disability and handicap. Particularly when considering hearing aid services for adult listeners, careful consideration has to be given to the particular form and application of inferences drawn from speech identification procedures if erroneous conclusions are to be avoided. It is argued that four such components relate to the statistical properties and discriminatory leverage of speech identification procedures, the choice of presentation level and conditions in regard to the auditory environment experienced by hearing-impaired clients, the extent to which speech tests based on segmental intelligibility provide appropriate information in relationship to perceived disabilities and handicaps, and the ways in which speech identification procedures to evaluate the potential benefits of signal-processing schemes for hearing aids are dependent upon sufficient listening experiences.