Bugnariu N1, Kowalewski V1, Thibodeau L2
1University of North Texas Health Science Center, Forth Woth, United States, 2University of Texas Dallas, Dallas, United States
Background: Traditionally, three sensory inputs - visual, vestibular, and somatosensory - are associated with the control of balance and have been investigated for their potential contribution to increased risk of falls. Recent evidence suggests additional sensory input, such as auditory input, may also contribute to balance control. Epidemiological studies have shown hearing loss is associated with balance deficits and increased risk of falls in older adults. Although current evidence reveals an association between hearing loss and balance difficulty, the mechanisms behind how and why hearing loss affects balance are unknown.
Purpose: 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.
Methods: 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.
Results: 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 did not significantly improve BKB-SIN or balance scores.
Conclusion(s): 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
Implications: Age-related hearing loss affects a large percentage of the older adult population. Individuals with hearing loss may be at greater risk of falling than individuals without hearing loss. One possible explanation includes reduced or conflicting auditory information increases the cognitive load and thus, attentional resources may be taxed particularly in older adults.
Keywords: Aging, Balance, Hearing loss
Funding acknowledgements: Texas Medical Research Consortium grant, RI 6042 and Neurobiology of Aging Training Program NIH - T32 AG 020494.
Purpose: 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.
Methods: 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.
Results: 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 did not significantly improve BKB-SIN or balance scores.
Conclusion(s): 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
Implications: Age-related hearing loss affects a large percentage of the older adult population. Individuals with hearing loss may be at greater risk of falling than individuals without hearing loss. One possible explanation includes reduced or conflicting auditory information increases the cognitive load and thus, attentional resources may be taxed particularly in older adults.
Keywords: Aging, Balance, Hearing loss
Funding acknowledgements: Texas Medical Research Consortium grant, RI 6042 and Neurobiology of Aging Training Program NIH - T32 AG 020494.
Topic: Older people; Human movement analysis; Health promotion & wellbeing/healthy ageing
Ethics approval required: Yes
Institution: University of North Texas Health Science center
Ethics committee: NorthTexas IRB
Ethics number: 2016-099
All authors, affiliations and abstracts have been published as submitted.
