Psychostimulant treatment and the developing cortex in attention deficit hyperactivity disorder
Philip Shaw1, Wendy S Sharp, Meaghan Morrison
1Child Psychiatry Branch, Bldg. 10, Center Dr., NIMH, Bethesda, MD 20892, USA. shawp@mail.nih.gov
The American Journal of Psychiatry
|September 17, 2008
Summary
Psychostimulant treatment for attention deficit hyperactivity disorder (ADHD) did not slow adolescent cortical thinning. Youths not on medication showed faster thinning than those on medication and typically developing peers.
Area of Science:
- Neuroscience
- Developmental Psychology
- Child Psychiatry
Background:
- Concerns exist regarding psychostimulant effects on adolescent brain development.
- Previous research has not prospectively examined these effects.
- Attention deficit hyperactivity disorder (ADHD) is commonly treated with psychostimulants.
Purpose of the Study:
- To prospectively investigate if psychostimulant treatment for ADHD is linked to altered cerebral cortex development during adolescence.
- To compare cortical thickness changes in treated vs. untreated youths with ADHD.
Main Methods:
- Neuroanatomic MRI scans were used to estimate cortical thickness changes in 43 youths with ADHD (ages 12.5 to 16.4 years).
- Two groups were compared: 19 untreated youths and 24 treated with psychostimulants.
- A control group of 294 typically developing youths without ADHD was used for comparison.
Main Results:
- Adolescents on psychostimulants showed different rates of cortical thinning compared to untreated peers in specific brain regions (motor strip, frontal gyrus, parieto-occipital).
- Untreated youths experienced more rapid cortical thinning than those on psychostimulants.
- Cortical thinning in untreated youths exceeded age-appropriate rates observed in typically developing peers.
Conclusions:
- The study found no evidence that psychostimulant use slows overall cortical mantle growth.
- Observed differences in thinning rates between treated and untreated groups did not correlate with clinical outcomes.
- Findings suggest psychostimulants do not impede overall adolescent cortical development.
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