The Effect of Hearing Loss on Balance Control

We investigated the contribution of auditory inputs to balance control in healthy young adults and older adults with normal hearing by simulating hearing loss, as well as in older adult with hearing loss by testing with and without hearing aids. Twenty healthy young adults with normal hearing, twenty older adults with normal hearing, and twenty older adults with hearing aids completed single- and dual- tasks consisting of a standardized audiology test (BKB-SIN) and maintaining standing balance in response to surface translations. Participants performed an auditory task of repeating back sentences from a standardized audiological test, the Bamford-Kowal-Bench Speech-In-Noise (BKB-SIN), played through wireless noise-cancelling headphones under randomized normal hearing and simulated hearing loss conditions or through surrounding speakers under hearing aid or no hearing aid condition. Simulated hearing loss was achieved using Adobe Audition software and a FFT logarithmic curve to manipulate sound volume and frequencies of standardized sentences according to age-related moderate hearing loss documented in literature. Backward surface translation perturbations inducing a forward loss of balance were synchronized with the auditory task and presented randomly at three levels (0m/s2, 2m/s2, and 5 m/s2). Primary outcome measures included: maximum Center of Pressure – Center of Mass (COP-COM) distance in response to perturbation during the first compensatory step, reaction time for initiating the first compensatory step, number of steps after loss of balance, and performance on the BKB-SIN. Repeated measures ANOVA were conducted for each dependent variable with respect to perturbation level and auditory condition. Results show reaction time decreases, maximum COP-COM distance increases, and number of steps increases as perturbation level increases across all groups. BKB-SIN scores and reaction time were significantly worse under the simulated hearing loss condition. Hearing aids significantly improved BKB-SIN scores, but not balance scores. Hearing loss affects reactive balance control, particularly while simultaneously attending to auditory tasks. Older adults maintain the ability to initiate compensatory steps, but they require an increase number of steps to regain balance. Individuals with hearing loss may be at greater risk of falling compared to individuals with normal hearing due to age-related cognitive and neurodegenerative changes associated with hearing loss