Left and Right Brain Hemispheres Electrical Activity Correlation during a Visual Continuous Performance Task in ADHD and Normal Children

The interaction between brain hemispheres plays a crucial role in cognitive functions, and abnormalities in this interaction may contribute to various brain diseases or disorders. This study investigates the correlation between the left and right brain hemispheres in children with Attention Deficit Hyperactivity Disorder (ADHD) and typically developing children across different brain regions and four frequency bands. Electroencephalographic (EEG) data were collected from 10 children with ADHD and 9 age-matched typically developing children during a visual continuous performance test. Three features were extracted from the EEG signals of 22 paired lateral brain channels: 1) the laterality of brain wave energy, 2) the correlation coefficient, and 3) mean phase coherence. Significant effects were observed for the laterality of brain waves’ relative energy across Bands ($\mathrm{F}(3)=24.27, p=0.0001$) and Region $(\mathbf{F}(21)=3.28, p=0.0001)$. The Beta band showed higher relative energy in the right hemisphere in frontal and central regions for both ADHD and normal groups, while lower frequency bands showed the opposite pattern. Correlation analysis revealed significant effects of Bands (F(3) = 11.72, $p=$ 0.0001) and Region $(\mathbf{F}(21)=87.46, p=0.0001)$. ADHD subjects exhibited higher Alpha band correlations between hemispheres in frontal channels than the normal group. Mean phase coherence analysis showed significant effects of Bands $(\mathbf{F}(3)=$ 12.68, $p=0.0001$) and Region ($\mathbf{F}(21)=26.24, p=0.0001$). Phase synchronization in the Beta band was lower between some frontal paired channels but higher in other paired channels for both groups. ADHD subjects exhibited higher phase synchronization in the Alpha band between anterior frontal channels and higher synchronization across all frequency bands in lateral occipital channels than normal subjects. These findings enhance our understanding of the impact of brain frequency interactions and disorders on hemispheric functions.