Decreased brain activity within the dorsolateral prefrontal cortex in adolescents during cognitive control tasks: a...

Adolescents with attention-deficit/hyperactivity disorder (ADHD) have reduced dorsolateral prefrontal cortex (DLPFC) activation during cognitive control tasks and weaker attention performance, with higher DLPFC activity linked to better complex attention, showing a connection between neural function and behavior. These findings support prefrontal dysfunction and hemispheric asymmetry in ADHD adolescents.

We aimed to compare brain activation during cognitive control tasks between adolescents with ADHD and typically developing (TD) individuals using functional near-infrared spectroscopy (fNIRS). Approach Sixty-eight adolescents participated: 30 ADHD and 38 TD, and were assessed using the Korean ADHD Rating Scale, Comprehensive Attention Test, Korean Beck Depression Inventory-II, and Korean Beck Anxiety Inventory. Brain activation during the Stroop Color and Word Test (ST) was measured with fNIRS. Psychological scales, cognition-related tests, and brain activation data were analyzed.

The ADHD group recorded decreased scores for congruence and incongruence of ST compared with the TD group. TD adolescents showed significantly greater increases in oxygenated hemoglobin concentration ( $\Delta {\mathrm{HbO}}_2$ ) in the prefrontal cortex (DLPFC) than adolescents with ADHD. DLPFC activation was negatively correlated with ADHD symptom severity (all participants). Correlations were observed between DLPFC $\Delta {\mathrm{HbO}}_2$ and cognitive function, particularly complex attention.

We found distinct brain activation patterns in the DLPFC for ADHD adolescents during cognitive control tasks. fNIRS measured these differences, helping to understand the developmental trajectory of ADHD in adolescents and providing evidence of functional impairment in complex executive function tasks.