New study on ADHD released

by Robin Wulffson, M.D.

LA Health Examiner

This article and more can be found at http://www.examiner.com/article/new-study-on-adhd-released.

On November 13, the findings of a new study on attention deficit hyperactivity disorder (ADHD) were reported at a conference held by the Society for Neuroscience (Washington, DC; November 12-16). According to the Los Angeles County Department of Public Health, 4.6% of children between birth and age 17 have been diagnosed at least once with attention deficit hyperactivity disorder (ADHD). Researchers from Wayne State University (Detroit, Michigan) noted that a brain area that helps coordinate mental activity works overtime in children with ADHD, reflecting the internal struggle to hold more than one concept in mind at a time. The researchers used a functional magnetic imaging scanner to track signs of neural activity among 19 affected children and 23 other children who were asked to remember a simple sequence of letters. A research team led by biologist Tudor Puiu discovered that a critical mental control area, called the dorsal anterior cingulate cortex, worked significantly harder and, perhaps, less efficiently among children with ADHD. They noted that this fundamental difference in brain function might be an underlying cause of the inattentiveness, impulsivity and focus problems that make it difficult for children with ADHD to concentrate in the classroom. Piuu noted, “Our findings suggest that the function as well as the structure of this brain area is different in children with ADHD.” He added, “It might explain the cognitive problems we see in the classroom.”

ADHD can be diagnosed in preschool-age children as young as four, according to new treatment guidelines issued by the American Academy of Pediatrics. Currently, the basic neurobiology responsible for the mental disorder is not understood; furthermore, the number of affected children has increased since 2003, according to a survey by the U.S. Health Resources and Services Administration. Furthermore, according to a National Institutes of Health (NIH) reported released in September, the portion of those children with the most severe symptoms who are treated with prescription stimulants, such as methylphenidate (Ritalin) and amphetamine (Adderall), has continued to increase.

The new findings add to growing biomedical evidence that those diagnosed with ADHD have unusual patterns of brain function that can persist well into adulthood. In general, the brain of child with ADHD matures normally; however, it may take up to three years longer to fully develop, particularly in areas at the front of the brain's cortex, which controls attention, reasoning and planning. Researchers have also reported a range of specific anatomical differences among ADHD children that may be linked to behavioral problems. Earlier this month, researchers at New York University's Langone School of Medicine reported that ADHD children appeared to have a significantly thinner cortex and less gray matter than other children in some areas involved in regulating attention and emotion. In another study, researchers noted that they had determined that ADHD children have differences in the caudate nucleus, which is involved in learning and memory, compared to other children.