Homotopic functional connectivity in patients with amnestic mild cognitive impairment / 中国医学影像技术

ABSTRACT

Objective: To observe interhemispheric and interregional resting-state functional connectivity using voxel-mirrored homotopic connectivity (VMHC) in patients with amnestic mild cognitive impairment (aMCI). Methods Totally 47 aMCI patients (aMCI group) and 43 gender, age and education matched normal controls (control group) were enrolled. The cranial structural MRI and resting-state fMRI data were collected. VMHC between both groups were compared to obtain the brain areas with altered VMHC. Using the altered VMHC areas as ROIs, the functional connectivity to the whole brain areas was calculated to observe the brain areas with different functional connection. Correlation analysis was performed between altered functional connection and neurocognitive scores. Results aMCI patients showed decreased inter-hemispheric VMHC primarily at bilateral inferior frontal gyrus, anterior insula and putamen. No area showed increased VMHC was found in aMCI patients. In aMCI patients, the functional connection of anterior insula to default mode network (DMN) regions including the posterior cingulate cortex (PCC) and the medial prefrontal cortex (MPFC) increased, and to attention control network and cerebellum decreased, and the functional connection of the left anterior insula to PCC and MPFC was positively correlated with recognition scores of auditory verbal learning test (r=0.38, 0.33, both P<0.05). Conclusion aMCI patients show deficits in inter-hemispheric VMHC and altered functional connection between different brain networks, suggesting an important new avenue for better understanding of the nature of cognitive changes in patients with aMCI.