Pathoconnectomics of cognitive impairment in small vessel disease: A systematic review

INTRODUCTION: Cerebral small vessel disease (CSVD) is a highly prevalent condition associated with diffuse ischemic damage and cognitive dysfunction particularly in executive function and attention. Functional brain imaging studies can reveal mechanisms of cognitive impairment in CSVD, although findings are mixed. METHODS: A systematic review integrating findings from functional magnetic resonance imaging and electroencephalography in CSVD is involved. RESULTS: CSVD damages long-range white matter tracts connecting nodes within distributed brain networks. It also disrupts frontosubcortical circuits and cholinergic fiber tracts mediating attentional processes. These changes, illustrated within a model of network dynamics, synergistically relate to neurodegenerative pathology contributing to dementia. DISCUSSION: The effects of CSVD on attention and executive functioning are best understood within a network model of cognition as revealed by functional neuroimaging. Analysis of network function in CSVD can improve characterization of disease severity and treatment effects, and it can inform theoretical models of brain function.