Sensory Reweighting for Postural Control in Older Adults with Age-Related Hearing Loss.

There is growing evidence linking hearing impairments and the deterioration of postural stability in older adults. To our knowledge, however, no study to date has investigated the effect of age-related hearing loss on the sensory reweighting process during postural control. In the absence of data, much is unknown about the possible mechanisms, both deleterious and compensatory, that could underly the deterioration of postural control following hearing loss in the elderly. The aim of this study was to empirically examine sensory reweighting for postural control in older adults with age-related hearing loss as compared to older adults with normal hearing. The center of pressure of all participants was recorded using a force platform and the modified clinical test of sensory interaction and balance protocol. The results suggest that individuals with age-related hearing loss displayed increased somatosensory reliance relative to normal hearing younger adults. This increased reliance on somatosensory input does not appear to be effective in mitigating the loss of postural control, probably due to the concomitant deterioration of tactile and proprioceptive sensitivity and acuity associated with aging. Beyond helping to further define the role of auditory perception in postural control, these results further the understanding of sensory-related mechanisms associated with postural instability in older adults.

Right-Ear Advantage for Unaided and Aided Speech Perception in Noise in Older Adults.

OBJECTIVE: To investigate whether the magnitude of the right-ear advantage (REA) for speech perception in noise decreased in aided conditions as compared with unaided conditions in older adults bilaterally fitted with hearing aids. A secondary aim was to determine the effect of audibility on the right- and left-ear processing for speech stimuli in both aided and unaided conditions. METHODS: Forty-two older adult, bilateral hearing-aid users were selected. Pure-tone audiometry and the hearing-in-noise test (HINT) were carried out and real-ear insertion gain (REIG) was measured in all participants. All HINT stimuli were delivered via loudspeakers in the free field in both aided and unaided conditions. RESULTS: Right-ear scores for HINT were significantly better than the left ear in both unaided and aided conditions. No significant differences in the magnitude of the REA between the unaided HINT and aided HINT scores were found. Regression models showed that audibility explained 47% and 53% of the variance in unaided HINT scores in the right and left ears, respectively. For the aided HINT scores, age and audibility explained 46% of the variability for the left-ear scores, while for the right ear, the only remaining significant variable in the model was REIG, which explained 12% of the right-ear HINT scores. CONCLUSION: Right-ear processing is significantly more efficient for speech stimuli in both unaided and aided conditions in older adults. Audibility affected unaided speech perception in right and left ears similarly however this was not the case in the aided condition. Audibility was associated with aided speech perception in noise in the left ear only.

State-of-the-art assessment allows for improved vestibular evoked myogenic potential test-retest reliability.

The goal of the present study was to evaluate the test-retest reliability values of myogenic responses using the latest guidelines for vestibular assessment. Twenty-two otologically and neurologically normal adults were assessed twice, on two different days. The analyses were carried out using interclass correlations. The results showed that the latest recommendations for vestibular assessment lead to test-retest reliability values that are as high, or greater, than those reported in previous studies. The results suggest that state-of-the-art testing, using the latest recommendations as well as electromyography control, improves reliability values of myogenic responses, more specifically for the cervical vestibular evoked myogenic potentials. The impact of small differences in experimental procedures on the reliability values of myogenic responses is also addressed.