Abstract
OBJECTIVE: This study aims to provide an objective evaluation of the therapeutic effects of methylphenidate (MPH) in children with attention deficit hyperactivity disorder (ADHD) by integrating clinical assessments, the go/no-go task, and functional near-infrared spectroscopy (fNIRS). METHODS: This study employed a two-part design. First, a cross-sectional comparison was conducted between 36 children with ADHD and 12 typically developing controls (TDC) to establish baseline neurocognitive and functional differences. Second, a pre-post intervention design was used to evaluate the effects of a 6-month MPH treatment on the 36 children with ADHD. All participants underwent clinical assessments, including the Swanson, Nolan, and Pelham IV Rating Scale (SNAP-IV) and the Weiss Functional Impairment Rating Scale (WFIRS), a go/no-go task, and fNIRS to measure average oxygenated hemoglobin (Δavg oxy-Hb) changes in targeted brain regions, including the medial prefrontal cortex (mPFC), dorsolateral prefrontal cortex (DLPFC), and temporal lobe (TL). RESULTS: The findings of the present study revealed that, at baseline, children with ADHD had significantly higher scores on the SNAP-IV and WFIRS than the TDC group. On the go/no-go task, accuracy for both go and no-go trials was significantly lower in the ADHD group than in the TDC group. Furthermore, fNIRS data indicated that the ADHD group had significantly lower Δavg oxy-Hb levels than the TDC group in the bilateral mPFC, right DLPFC, and bilateral TL. After 6 months of MPH treatment, children with ADHD showed significant reductions in SNAP-IV and WFIRS scores. Concurrently, they showed significantly increased accuracy on both go and no-go trials, along with significantly decreased reaction times on go trials. Furthermore, Δavg oxy-Hb levels increased significantly in the right mPFC. CONCLUSION: Our findings suggest that activation in the right mPFC is a viable objective neurofunctional biomarker for monitoring MPH treatment response using fNIRS. Concurrently, a multimodal assessment strategy integrating clinical evaluations, neuropsychological testing (go/no-go task), and fNIRS holds significant promise as a robust method for objectively determining the therapeutic efficacy of MPH in pediatric ADHD.