Aberrant Spatial and Temporal Prefrontal Activation Patterns in Medication-Naïve Adults with ADHD

Area of Science:

• Neuroscience
• Psychiatry
• Medical Imaging

Background:

• Attention-deficit hyperactivity disorder (ADHD) diagnosis relies on subjective measures, highlighting the need for objective biomarkers.
• Previous near-infrared spectroscopy (NIRS) studies show reduced prefrontal cortex (PFC) activation in adults with ADHD during verbal fluency tasks (VFT).

Purpose of the Study:

• To investigate detailed temporal and spatial patterns of aberrant prefrontal and temporal brain activation in drug-naïve adults with ADHD using NIRS.
• To explore the potential of NIRS-derived hemodynamic responses as objective biomarkers for ADHD.

Main Methods:

• Employed a cluster-based non-parametric randomization test with high temporal resolution (0.1 s) to compare oxygenated-hemoglobin [oxy-Hb] time-course changes.
• Included 101 participants: 63 drug-naïve adults with ADHD and 38 healthy controls (HC).
• Utilized a verbal fluency task (VFT) to elicit prefrontal cortex activity.

Main Results:

• Adults with ADHD demonstrated significantly smaller [oxy-Hb] activations in bilateral PFC and temporal regions compared to HC.
• Aberrant [oxy-Hb] activation patterns in ADHD varied with task time and brain location, with greater differences observed in left-sided regions.
• High-resolution analysis revealed more detailed abnormal activation patterns than previously reported.

Conclusions:

• NIRS can detect detailed, spatially and temporally specific aberrant brain activation patterns in adults with ADHD during VFT.
• These findings suggest that high-resolution NIRS analysis of hemodynamic responses may serve as a valuable objective neuroimaging biomarker for ADHD.