P3‐379: Cognitive Intraindividual Variability in Early Alzheimer's Disease Is Related to Weakening of Functional Network Anticorrelations
Year: 2019
Type: article
Abstract: In cognitively normal older adults, task-positive networks, such as the dorsal attention network (DAN), show greater neural recruitment in response to attention-demanding tasks than at rest, whereas the task-negative default mode network (DMN) shows the opposite pattern. The inverse relationship, or anticorrelation, between the two networks likely reflects efficient competition for cognitive resources. We hypothesized that if functional connectivity between the DAN and DMN is dysregulated in early Alzheimer's Disease (AD), then anticorrelations will be weaker and increased cognitive intraindividual variability (IIV), or increased inconsistencies in cognitive performance, will occur. Neuroimaging and cognitive measures from the Alzheimer's Disease Neuroimaging Initiative (ADNI) were used to assess within and between network functional connectivity and IIV in cognitively normal older adults and those with early AD. Analyses were then replicated using data from Washington University's Knight Alzheimer's Disease Research Center (ADRC) to ensure statistical validity. In the ADNI sample, cognitive IIV was greater in individuals with early AD compared to cognitively normal older adults. Furthermore, the relationship between cognitive IIV and the DAN-DMN anticorrelation was weaker for individuals with early AD than cognitively normal individuals. Preliminary analyses on data from the ADRC showed similar results. Collectively, the results from ADNI and ADRC support conclusions that in early stages of AD, overall cognitive functioning becomes less consistent, and that decreases in cognitive consistency are associated with a breakdown in functional network anticorrelations. This study provides insight into how alterations in the dynamics of functional networks give rise to behavioral changes in early AD.
Source: Alzheimer s & Dementia
Authors: Karin Meeker, Jill Waring
Institution: Saint Louis University
Language: English
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W2980924075