Estimated regional white matter hyperintensity burden, resting state functional connectivity, and cognitive functions in older adults

Abstract

ObjectiveWhite matter hyperintensities (WMH) are linked to deficits in cognitive functioning, including cognitive control and memory; however, the structural and functional mechanisms are largely unknown. We investigated the relationship between estimated regional disruptions to white matter fiber tracts from WMH, resting state functional connectivity (RSFC), and cognitive functions in older adults. DesignCross-sectional study. SettingCommunity. ParticipantsFifty-eight cognitively-healthy older adults. MeasurementsTasks of cognitive control and memory, structural MRI, and resting state fMRI. We estimated the disruption to white matter fiber tracts from WMH and its impact on gray matter regions in the cortical and subcortical frontoparietal network, default mode network, and ventral attention network by overlaying each subjects WMH mask on a normative tractogram dataset. We calculated RSFC between nodes in those same networks. ResultsThe interaction of estimated regional WMH burden and RSFC in cortico-striatal regions of the default mode network and frontoparietal network was associated with memory retrieval. Models predicting working memory, cognitive inhibition, and set-shifting were not significant. ConclusionsFindings highlight the role of circuit-level alterations at the structural and functional levels in resting state networks that are related to WMH and impact memory retrieval in older adults.