Research from Lin and colleagues at Johns Hopkins University and the National Institute on Aging suggests that the greater the degree of hearing loss, the greater the risk of dementia. The incidence of dementia increased by 2x for those with mild hearing loss, 3x for those with moderate hearing loss, and 5x for those with severe hearing loss. Lin also notes that hearing loss may be associated with cognitive decline that is possibly mediated by social isolation, cognitive load, or through a direct neuro-biologic mechanism.
Additional preliminary research by Crain & colleagues at the Hearing Cooperative Research Centre at Macquarie University in Australia supports the notion of using hearing aids to develop new neural pathways. Although it’s still too soon to tell exactly what is happening in the brain, these researchers feel that the use of hearing aids in adults may assist in delaying the onset of dementia, as it appears that perceptual changes are taking place in the brain as it adjusts to the new information provided by hearing aids. It is also noted that this is supported by anecdotal reports from adult patients who are initially unhappy with their hearing aids, but then report significant improvement after a month or two of hearing-aid use.
Crain, S. (2014). Hearing disorders and brain plasticity. Round Table2: Central Auditory Plasticity. XXXII World Congress of Audiology, Brisbane, Autralia.
Lin, F. (2011). Hearing loss and cognition among older adults in the United States. J. Gerentol, 66A(10):1131-1136.
Lin, F. et al. (2011), Hearing loss and incident dementia. Arch Neurol, 68(2):214-220.