Investigating Visual Function and Cortical Structure in Groups with (or at Risk for) Alzheimer’s Dementia
Year: 2020
Type: dissertation
Abstract: Poor sensory performance is cross-sectionally associated with poorer cognition and increases risk for cognitive decline and Alzheimer’s dementia (AD). The purpose of this study was to characterize the degree of visual impairment in individuals with (or at risk for) dementia and explore the effects of this sensory-cognitive relationship on brain structure. \n \nUsing the Comprehensive Assessment of Neurodegeneration and Dementia (COMPASS-ND) dataset, we analyzed vision and imaging data from three diagnostic groups: individuals with subjective cognitive decline (SCD; N = 53), mild cognitive impairment (MCI; N = 102), and mild AD (N = 45). We characterized used ANCOVAs to determine whether visual performance on reading acuity and contrast sensitivity differed as a function of clinical diagnosis. Cortical thickness and volume were extracted using FreeSurfer, and hierarchical regression analyses were done to determine whether visual performance predicted brain structure (i.e., cortical thickness and volume) beyond diagnostic group membership. \n \nWe found that the AD group performed significantly worse on reading acuity and contrast sensitivity compared to the SCD and MCI groups, which did not differ from each other. Despite our independent findings that visual performance differs across diagnostic groups and that group membership predicted cortical structure, our results demonstrate that visual performance does not predict cortical structure above and beyond clinical diagnosis. Our findings support the hypothesis that atrophy in underlying visual areas and pathways is responsible for the functional vision deficits observed in AD.
Author: Sana Rehan
Language: English
Subfield: Psychiatry and Mental health
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W3116729425