Disrupted functional connectivity of default mode network and executive control network in patients with vascular cognitive impairment, no dementia

Abstract

Objective: To investigate functional connectivity within default mode network (DMN) and executive control network (ECN) in vascular cognitive impairment, no dementia (VCIND). Methods: Twenty-eight VCIND patients and sixteen healthy controls were recruited. A seed-based connectivity analysis was performed using data from resting-state functional magnetic resonance imaging (fMRI). Based on previous findings, posterior cingulate cortex (PCC) and dorsolateral prefrontal cortex (DLPFC) were chosen as regions of interest to study these networks. One-sample t-test and two-sample t-test were used for statistical analysis. Results: Compared with the controls, the VCIND group exhibited increased functional activity in such DMN regions as the left inferior temporal gyrus, parahippocampal gyrus, and medial frontal gyrus. The VCIND group had decreased functional connectivity of DMN at right superior frontal gyrus, left mid-cingulate area, the medial part of left superior frontal gyrus, and bilateral medial frontal gyrus. The VCIND group also showed decreased functional connectivity of ECN primarily at left inferior parietal gyrus, right angular gyrus, right middle occipital gyrus, and right middle frontal cortex. Conclusions: Increased functional connectivity within DMN and decreased functional connectivity within ECN suggested dysfunction of these two networks, which might be associated with the cognitive deficits in patients with VCIND. These findings may help us understand the pathogenesis and clinical characteristics of VCIND.

Keywords

vascular cognitive impairment (VCI) / VCI no dementia (VCIND) / functional connectivity / default mode network / executive control network