Alteration in resting state EEG functional connectivity in children with Attention deficit/hyperactivity disorder (ADHD)

Attention deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders in children. In this study, we investigated alterations in functional connectivity in children with ADHD compared to healthy controls (HC) using high-density electroencephalographic (EEG) data. We computed current source densities using the exact low-resolution electromagnetic tomography (eLORETA) method. Then, the lagged phase synchronization was used to evaluate group differences in functional connectivity. We also explored differences in network topological properties between ADHD and HC. Compared to HC, ADHD was characterized with a decrease in delta LPS in the occipital regions. ADHD also showed higher LPS in theta and alpha bands over frontal, temporal, central and occipital areas. Both ADHD and HC showed the small-world properties (S>1) in all frequency bands. Compared to HC, ADHD was further characterized by increased global efficiency and decreased average clustering coefficient in delta and theta band, respectively. Our findings show that the EEG source connectivity analysis can better characterize alterations in functional connectivity in children with ADHD.