Functional network connectivity changes in children with attention-deficit hyperactivity disorder: A resting-state fMRI study.

The study aimed to investigate the pathologic mechanism of functional brain regions in attention-deficit hyperactivity disorder (ADHD) patients through making comparisons of normal and ADHD children from the perspective of the network nodes of brain network and the intensity of functional connection between bilateral of hemispheres by resting-state functional magnetic resonance imaging (fMRI). Thirty-five ADHD and forty-two children were examined by resting-state functional magnetic resonance imaging (fMRI) scans. Data analysis was done via the degree centrality (DC) and voxel-mirrored homotopic connectivity (VMHC) approaches. Compared with healthy subjects, the ADHD group exhibited significantly decreased DC values in the right posterior cingulate gyrus, left medial superior frontal gyrus, right inferior parietal gyrus, right middle frontal gyrus, left superior frontal gyrus and right superior frontal gyrus. Children with ADHD also exhibited some areas with increased DC values compared with healthy children. These regions included the cerebellar anterior lobe, right middle occipital cortex, left middle cingulate gyrus and right middle cingulate gyrus. VMHC analysis all revealed positive activation in a range of brain regions when comparing ADHD and normal children, suggesting that the VMHC scores of children with ADHD were higher in the bilateral superior frontal lobe, bilateral middle occipital lobe, and bilateral cerebellar anterior lobes. This work provides a new approach for examining the neural mechanisms underlying ADHD, demonstrating that the DC and VMHC methods enabled more comprehensive analysis that can be cross-checked.