Brain abnormalities in adults with Attention Deficit Hyperactivity Disorder revealed by voxel-based morphometry

Area of Science:

• Neuroimaging
• Neuroscience
• Psychiatry

Background:

• Attention Deficit Hyperactivity Disorder (ADHD) often persists into adulthood, affecting approximately 50% of childhood cases.
• While pediatric brain changes in ADHD are documented, adult studies remain limited and inconclusive.
• Understanding adult ADHD brain structure is crucial for effective treatment strategies.

Purpose of the Study:

• To investigate structural brain differences in adults diagnosed with ADHD compared to healthy controls.
• To identify specific brain regions affected by ADHD in the adult population.
• To explore the relationship between stimulant medication dosage and brain structure in adult ADHD.

Main Methods:

• Voxel-based morphometry (VBM) analysis was employed.
• The study included 44 adults with ADHD (Combined subtype) and 44 age-, sex-, and IQ-matched healthy controls.
• Participants' ages ranged from 18 to 54 years.

Main Results:

• Adult ADHD patients displayed reduced gray matter (GM) volume in the right supplementary motor area (SMA).
• Further analysis revealed GM reductions in the subgenual anterior cingulate (ACC) and right dorsolateral prefrontal cortex (DLPFC).
• Increased GM volume was observed in the basal ganglia, specifically the left caudate nucleus and putamen. A positive correlation was found between cumulative stimulant dose and GM volume in the right SMA and DLPFC.

Conclusions:

• Adult ADHD is associated with structural brain alterations within the 'cool' executive function network.
• These findings highlight specific neuroanatomical differences in adult ADHD.
• Long-term stimulant medication may potentially normalize gray matter alterations observed in adult ADHD patients.