Clinical Trial: PC-Based Rehabilitation of Auditory Function

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: PC-based Rehabilitation of Auditory Function

Brief Summary: Many older subjects experience difficulty in understanding speech in noisy environments. Part of this problem is related to changes that occur in the ear with age and compromise the hearing of high-pitched sounds. Another part of the problem with speech understanding relates to changes with age in the neural circuits of the brain that process different speech sounds. Evidence suggests that these changes in neural circuits are particularly large if hearing loss is present. Thus, while hearing aids may help compensate for hearing deficits by amplifying speech sounds, additional treatment is necessary to restore optimal neural connections in the brain so that speech sounds can be accurately distinguished from each other. We are developing PC-based training programs in an attempt to restore optimal neural connections. The current randomized trial will evaluate whether two months of training to improve the ability to discriminate different consonant sounds in noise will also improve the understanding of continuous speech and enhance auditory memory and other high-level auditory functions.

Detailed Summary:

More than 300,000 veterans with sensorineural hearing loss (SNHL) are fitted with VA-issued hearing aids (HAs) each year with the primary goal of improving their understanding of speech. Even older veterans without hearing loss experience a gradual decline in speech discrimination due to age-related changes in auditory function that compromise speech understanding in everyday environments. Neuroplastic reorganization within the central auditory system due to SNHL and aging contribute to these effects and compromise subjects' ability to process phonetic cues that are essential for understanding speech in noise. As a consequence, even when a HA restores high frequency signals to the cochlea in a patient with SNHL, speech understanding will remain suboptimal in the absence of rehabilitative perceptual learning.

We have developed perceptual learning paradigms that drive this rehabilitative reorganization and significantly improve speech discrimination in new HA users. We now propose to test improved training paradigms in new and experienced HA users and older subjects with normal hearing. In Exp. 1 we will evaluate baseline speech discrimination in these populations using speech-reception thresholds (SRTs) in sentences, consonant-vowel-consonant nonsense syllable tests (CVC-NST), tests of tone-pattern discrimination, and tests of auditory short-term verbal memory (ASTVM). An analysis of the correlations of these measures will provide information about basic processes underlying impaired word and sentence identification. In Exp. 2 we will investigate the effects of CVC-identification training using performance-adapted masking noise. Based on our previous results, we anticipate that training will significantly improve CVC-NST scores. We will examine the extent to which training improves SRTs, tone-pattern processing, and ASTVM. In Exp. 3 we will train subjects in a tone-pattern
Sponsor: VA Office of Research and Development

Current Primary Outcome: .Speech Discrimination Ability [ Time Frame: Subjects will receive two months of PC training and be tested before and after 2-months of training with speech tests in the laboratory.. ]

Mean consonant identification threshold improvement measure in z-scores (re normal hearing subjects) on consonant and sentence discrimination tests. Additional computerized tests measured auditory short-term verbal memory, and auditory pattern discrimination. The results were compared with baseline performance in the listener group as well as performance in other older hearing impaired subjects who used hearing aids, but who did not undergo training. In the next month, we will published two manuscripts in PLoS ONE describing (1) the benefits of hearing aids on speech comprehension in the absence of perceptual training; (2) the additional benefits of perceptual training. More metholdological details can be found in those manuscripts.


Original Primary Outcome: computer measurements of syllable processing, auditory short-term verbal memory, sentence reception, and auditory pattern discrimiantion [ Time Frame: Subjects will receive 2-months of PC-training and be tested over an 8-mo period. ]

Current Secondary Outcome:

Original Secondary Outcome:

Information By: VA Office of Research and Development

Dates:
Date Received: July 24, 2008
Date Started: July 2008
Date Completion:
Last Updated: January 15, 2015
Last Verified: January 2015