Exploring the Relationship Between Depression and Attention-Deficit/Hyperactivity Disorder Symptoms in Children Using Brain Activity Monitoring.

OBJECTIVE: Although depression is a common comorbidity in children with attention-deficit/hyperactivity disorder (ADHD), its neurophysiological relationship according to each symptom has rarely been explored. This study aimed to inform clinical practice by exploring the neurophysiological underpinnings of depression comorbidity in ADHD. METHODS: We conducted a cross-sectional study of 87 children with ADHD (68 males). Resting quantitative electroencephalography (qEEG) recordings were collected with eyes closed. We used various questionnaires to evaluate ADHD symptoms severity, depression, and anxiety. Pearson correlation coefficients were used to investigate the relationship between the z-score relative spectral power of qEEG and each psychological symptom. Data were analyzed using IBM SPSS 27.0. RESULTS: The study's findings indicated that theta activity at the frontal, central, and parietal locations had a negative correlation with the severity of ADHD symptoms in children diagnosed with ADHD. In contrast, alpha activity in these same regions demonstrated a positive correlation with ADHD symptom severity. Additionally, delta activity in the regions was negatively correlated with depression severity. CONCLUSION: These findings suggest that alpha and theta activity might serve as a reliable neurophysiological marker of ADHD symptom severity, while delta activity might function as a reliable biological marker of depression severity in children with ADHD. However, further research is needed to generalize the results of this study.