Semantic Network Alterations in Early Alzheimer\u27s Disease and Mild Cognitive Impairment

This study examined networks associated with picture naming in both healthy and pathological aging. Adults with Alzheimer’s disease and mild cognitive impairment demonstrated greater reliance on domain-general regions and less reliance on canonical language areas compared to their healthy counterparts. Task-residual data and partial correlation were also used to examine functional connectivity across three semantic category networks (animals, tools, and vehicles). Alterations in functional connectivity in Alzheimer’s disease and mild cognitive impairment were characterized by both increases and decreases in network nodes compared to healthy controls, suggesting a pattern of dedifferentiation and overall network disruption across categories. Furthermore, nodes including the right ventral thalamus and caudate as well as the left fusiform gyrus appeared to be particularly vulnerable to functional connectivity changes