This supplement seeks to advance understanding of Alzheimer's disease (AD) and Alzheimer's disease related dementias (ADRD) by clarifying relationships between measures of visual processing, cognitive functioning, and perceptual learning in a diverse older adult population, including those with prodromal AD/ADRD and MCI. The proposed supplement is within the scope of the funded project, entitled ?Mediators and Moderators of Perceptual Learning? which already aims to examine such relationships in older adults without dementia. Here we propose to expand inclusions to better target older adults with possible prodromal AD/ADRD and to add new measures to better characterize cognitive function in this population. Indeed, the well-documented age-related declines that occur in vision and in cognition as a result of normal aging are considered major issues in regard to individuals' health and well-being as well as with respect to more global economic and social policies, with these issues being more severe, and thus taking on even greater relevance, in the context of AD/ADRD. The proposed supplement is premised on the observation that age-related declines in centrally mediated visual processes may explain unaccounted for variance in estimates of higher-cognitive function and that likewise cognitive factors may explain unaccounted for variance in estimates of visual functions. As such, whether in the context of understanding outcome measures of perceptual learning (such as in the current proposal), or whether testing vision in the clinic, it is essential to consider measures of cognition, and how they change, as a moderating factor in estimating visual processes. Further, measures of central visual processes may help identify individuals with prodromal AD/ADRD. In this manner we can gain new insights into the reciprocal role that vision and cognitive processes play in the aging process from both a mechanistic and a practical perspective. This is likely to stimulate additional activity by giving rise to a unique data-set that can be used as a foundation for new lines of research that can potentially lead to new behavioral biomarkers of prodromal AD/ADRD. Thus, the supplement can also promote development of new procedures to more accurately measure vision and cognitive function in older adults suffering from cognitive impairments.
The proposed research is relevant to public health, and in particular, the mission of the NEI to support research on visual disorders, mechanisms of visual function and preservation of sight, because a greater understanding of mechanisms related to perceptual learning can inform new therapies for treating low vision, which in turn has the potential to benefit millions of individuals suffering from low vision. Declines in vision are particularly common in older adults and thus increasing our understanding of how to create effective means of improving vision is also highly relevant to the mission of the NIA to support research on aging and the health and well- being of older people. In addition to strongly aligning with the missions of the NEI and NIA, the proposed re- search cuts across the bounds of numerous other NIH agencies, including the NCI, NIMH, NIAAA, NINCD, NI- DA, NINDS, in that all of these agencies work with populations who could gain direct benefits from successful approaches to utilizing behavioral methods to enhance human well-being and performance.
