Researchers move closer to ADHD imaging biomarker

ADHD (attention deficit hyperactivity disorder): Hmm... that's controversial. To some people it's a complex developmental and psychiatric disorder, and to others it's code for badly behaved children that simply need some barriers and should just knuckle down and work. The use of functional magnetic resonance imaging (fMRI--specialized imaging that detects neural activity based on blood flow) has identified changes in the brain that can be visualized and used as biomarkers in diagnosis.

In a study presented at RSNA 2011 (Radiological Society of North America 97th Scientific Assembly and Annual Meeting), researchers used fMRI to scan the brains of children (half with ADHD, half without) while the children took a sustained attention test, which assessed working memory. The children with ADHD had abnormal functional activity in regions of the brain involved in the processing of visual attention information, as well as disruption in communication in the brain regions within this visual attention-processing pathway.

"Diagnosing ADHD is very difficult because of its wide variety of behavioral symptoms," said lead researcher Xiaobo Li, Ph.D., assistant professor of radiology at the Albert Einstein College of Medicine in New York. "Establishing a reliable imaging biomarker of ADHD would be a major contribution to the field."

ADHD affects up to 8% of children, but there is no single test for it, resulting in ADHD potentially being overdiagnosed in some groups of children and underdiagnosed in others. A biomarker test could take the doubt out of the diagnosis, stopping overmedication of children who are just difficult to manage, and allowing help for those who genuinely are having attention and learning issues, which can last into adulthood. It could also take away the stigma for children with ADHD and their parents, and end once and for all the idea that ADHD does not exist.

- read the release
- see the abstract