There is no simple diagnostic test that can confirm, or rule out, attention-deficit hyperactivity disorder (ADHD)—the diagnosis requires a detailed evaluation by an experienced clinician. Findings of cortical thinning are statistically significant when groups of individuals with ADHD are compared to those without ADHD, but cortical measures cannot be used to assess whether a specific individual has a relatively thinner cortex than expected, or has ADHD. Also, we do not yet know whether cortical thinning in early development occurs only among children with ADHD. It is possible this occurs in other conditions as well. Here, as with other dilemmas, we need further research to inform the question. There are no known risks to doing an MRI in a child, but there is no reason to do so, unless advised by a neurologist (but not to diagnose ADHD).
Rachel G. Klein, Ph.D.
Scientific Council Member
1995 NARSAD Distinguished Investigator Grantee
2004 Ruane Prize for Outstanding Achievement in Child & Adolescent Psychiatric Research
Professsor of Psychiatry, New York University Child Study Center