Resting-state FMRI Of ALFF And FC Analysis In Children With Attention Deficit Hyperactivity Disorder

Objective Amplitude of low-frequncey fluctuation (ALFF) and FunctionalConnectivity(FC)of the resting-state fMRI was used to investigate the difference of thespontaneous neuronal activity between ADHD and normal children, and the correlationbetween the activity level of brain and symptom severity. Methods Thirty-two childrenwith ADHD of school age and thirty age and gender matched controls were experiencedresting-sate fMRI scans while blood oxygenation level dependent (BOLD) signal wasacquired to calculate the ALFF and FC. Linear correlations were performed between theaggregate score of RS-IV and ALFF voxels in ADHD patients. Results Part1：Comparedto the controls,the ADHD group exhibited decreased ALFF in right superior frontal gyrus(BA9,t=-4.61), left superior medial frontal gyrus (BA10,t=-3.63), left mediate frontal(BA46, t=-4.09),and left anterior cingulate cortex (BA24,t=-4.02). Meanwhile, it showedincreased ALFF in the medial orbitofrontal cortex (BA11, t=3.52), right cuneus gyrus(t=3.93), right mediate occipital gyrus(BA19, t=3.82), right cerebellum (BA37, t=3.77),right mediate temporal gyrus (BA37, t=3.76), and left paracentral lobe (BA6, t=3.77).Altered ALFF in left superior medial frontal gyrus (p=0.009, r=0.492)and the right cuneusgyrus (p=0.024, r=0.433) showed correlation with the aggregate score of RS-IV. Part2:Compared with the control group, ADHD patients exhibited enhanced functionalconnectivity with the ROI-1in left supplementary motor area, the left interior frontal, theleft orbitofrontal cortex area; reduced functional connectivity in the right occipital. Andenhanced functional connectivity with the ROI-2in right temporal, left orbitofrontal cortex,left superior medial frontal, right anterior cingulate cortex, left middle frontal gyrus;reduced functional connectivity in the right middle frontal and right cerebellum.Conclusions Part1. ALFF could indicate exhibited the regional spontaneous neuronalactivity of ADHD. We found that decreased activity in prefrontal cortex was correlated tosymptom severity. Part2. Our data support the hypothesis that ADHD and normal children both existence functions distinction in caudal and rostral of ACC; ADHD groups exhibitedreduced functional connectivity in ACC with default mode network, the caudal of ACCexhibited enhanced functional connectivity with the regions related motor cortex, ACC ascoterminous of executive function circuit is an important brain areas for ADHD etiologyand pathogenesis.