Description

Major demographic transitions are underway in the developed world and adults aged 65 and over are the fastest growing segment of the United States population. Aging is associated with the deterioration of sensory and perceptual processes as well as a decline in cognitive functioning including attention and working memory. Advancing age is also associated with an increased risk of developing dementia including Alzheimer's disease (AD), a progressive neurodegenerative condition. The ε4 allele of APOE is one of three common alleles generated by cysteine/arginine substitutions. Although multiple genetic and environmental risk factors are involved in AD, the possession of the ɛ4 allele is recognized as the most common identifiable genetic risk factor for late-onset AD. The proportion of patients with AD that is attributable to the APOE ε4 is estimated to be 20% in people aged ≥ 55 years 5. Although the APOE 4 allele increases the risk of developing AD by three to fifteen times, recent studies have shown that the risk can be modified by non-genetic factors, including high education and leisure activities.

Another significant and related problem of aging is a decline in hearing abilities. Age-related hearing loss is a common problem for older adults, leading to communication difficulties, isolation, and cognitive decline. The difficulty understanding speech in noisy environments is one consequence of hearing loss that is particularly difficult to restore with hearing aids. Speech-in-noise (SIN) perception appears to be supported by both the efficiency of bottom-up sound encoding and the influence of higher-level top-down processes such as auditory working memory and selective attention. Decline in hearing and reduction in communication are associated with an increased rate of cognitive decline and the development of dementia in older adults. Decline in SIN perception can also make it difficult for aging individuals to engage socially and maintain relationships and has been linked to loneliness and depression. Indeed, poor SIN perception may contribute to cognitive decline and increased risk of dementia both through taxing cognitive load and decreasing social engagement. As a result, there is a critical need for effective and accessible interventions that target hearing, particularly interventions that are motivating and engaging and can be applied to the expanding population of older adults, especially those at higher risk of AD. The investigators will conduct an individually randomized group treatment trial to investigate the effects of choir training and its underlying neurobiological mechanisms on SIN perception and psychosocial well-being in adults ages 65 and older half carriers of APOE ε4 and the other half of non-carriers. The investigators will randomly assign approximately 66 older adults to a 16-week: (1) community choir program or (2) a group music listening program.