Large-Scale Network Connectivity as a Predictor of Age: Evidence Across the Adult Lifespan From the Cam-CAN Data Set

Changes in brain connectivity patterns as a function of age have been recently proposed to underlie differences in cognitive abilities between young and older adults. These shifts track patterns of increased functional coupling between the executive control network (ECN)-a network of prefrontal and parietal areas that is broadly implicated in externally directed attention and cognitive control-and default mode network (DMN) regions-most commonly associated with internally directed cognitive activity. Although age-related changes in ECN-DMN coupling are well characterized, the contributions of the salience network are less clear. Furthermore, given the salience network's crucial role in arbitrating ECN-DMN functional connectivity, it is important to understand its contribution throughout the adult lifespan. Here, we used the data from a large cohort (N = 547) of participants from the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) database (18-88 years old) to investigate first whether resting-state ECN-DMN functional connectivity predicts age. We further examined how connectivity between ECN, DMN, and salience network regions impacts the hypothesized age-related increased connectivity between ECN and DMN areas. Multiple regression analyses revealed that connectivity between dorsolateral and ventromedial prefrontal cortex and parietal regions, including the precuneus, accounted for a significant portion of age variability and that the inclusion of connectivity between orbitofrontal insula, anterior insula, and anterior cingulate regions of the salience network improved the models' explanatory power. Additional age cohort analyses further highlighted that these relationships vary across the lifespan. We discuss how these findings expand on our current understanding of the variations in large-scale intrinsic network connectivity as a function of healthy aging. Public Significance Statement Differences in cognitive abilities between young and older adults may be attributed to changes in brain connectivity patterns as a function of age. In this study we analyzed a large cohort of participants from the publicly-available Cam-CAN brain imaging database and showed that functional connectivity among large-scale brain networks predicts age and varies across the lifespan. Our results expand on our current understanding of brain connectivity as a function of healthy aging.