Article

Anatomic Brain Abnormalities in Monozygotic Twins Discordant for Attention Deficit Hyperactivity Disorder

Child Psychiatry Branch, National Institute of Mental Health (NIMH), 베서스다, Maryland, United States
American Journal of Psychiatry (Impact Factor: 12.3). 10/2003; 160(9):1693-6. DOI: 10.1176/appi.ajp.160.9.1693
Source: PubMed

ABSTRACT

To examine brain-behavior relationships in attention deficit hyperactivity disorder (ADHD), the authors obtained magnetic resonance imaging (MRI) scans of monozygotic twins discordant for ADHD.
National recruitment was followed by in-person assessment. MRI scans were measured algorithmically for nine pairs of monozygotic twins discordant for ADHD.
The affected twins had significantly smaller caudate volumes (mean difference=-0.56 ml, CI=-0.92 to -0.21) than their unaffected co-twins.
These results provide further support for striatal models of ADHD pathophysiology.

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    • "In addition, hippocampal volume in girls and the amygdala volume in boys are greater (Fig. 5). This difference in hippocampal and amygdala volume may be associated with attention deficit, hyperactivity and Tourette's syndrome (disorder) and neuropsychiatric disorders such as earlyonset obsessive-compulsive disorder (Aylward et al., 1996; Castellanos et al., 2003; Peterson et al., 2003). "
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    • "However, only a limited number of studies have been published on ADHD discordant MZ twin pairs to date (Castellanos et al., 2003; Lehn et al., 2007; Pearsall- Jones et al., 2008, 2009; Sharp et al., 2003; Van't Ent et al., 2009). Results from these studies report differences in brain anatomy, i.e. reduced caudate nucleus and prefrontal lobe volumes in cases (Castellanos et al., 2003), and the identification of environmental risk factors such as low birth weight, delayed motor development, and being born the second twin in the pair (Lehn et al., 2007). Furthermore, results from functional Magnetic Resonance Imaging (fMRI) in twins pairs discordant and concordant for ADHD indicate that attention problems caused by genetic versus non-shared environmental factors, affect the brain in different ways. "
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