More delays in brain growth seen with ADHD

August 15, 2012 By Amanda Gardner, HealthDay Reporter
More delays in brain growth seen with ADHD
Latest study finds the covering of the cerebral cortex developed more slowly.

(HealthDay) -- Researchers have uncovered more evidence that certain types of delays in brain development seem to be related to a heightened risk for attention-deficit hyperactivity disorder (ADHD).

A new study appearing in the current issue of the journal Biological Psychiatry found that development of the cortical surface -- which covers the region of the brain known as the cerebral cortex -- was slower in children with ADHD.

This complements previous research from the same team of scientists that found normal childhood thickening of the also is delayed in the brains of children with ADHD.

At this point, the findings have no but they may one day help point to genes that control the timing of , said study author Philip Shaw, head of the Neurobehavioral Clinical Research Section at the National Institute.

That, in turn, may lead to new insight into how to help kids with ADHD.

"This is more about understanding the causes and the underlying changes in the brain that happen with ADHD," added Jennifer Vannest, assistant professor of neurology at Cincinnati Children's Hospital. Vannest was not involved with the study.

Shaw and his colleagues did multiple brain-imaging scans of 234 children with ADHD and 231 normally developing children who served as controls. Scans began when the children were about 10 years old and continued until they were 17.

Kids with ADHD did not reach "peak" development in the cortical surface until 14.6 years of age, compared with 12.7 years in normally developing kids.

"In healthy kids, the surface of the -- the cortex -- increases during adolescence, reaches a peak, then stabilizes into adult dimensions," Shaw explained.

This report, added to the previous findings on cortical thickness, suggest that the same mechanisms may govern development of different areas of the brain. At this point, however, it is unclear what those mechanisms might be.

The finding also may help settle the ongoing question of whether ADHD is due in part to a delay in development processes or whether it is due to a complete derailing of typical development, Shaw said.

"We find that the overall pattern or sequence in which different parts of the brain [mature] was quite similar between kids with ADHD and those who didn't have ADHD, but just a bit delayed," Shaw said. "In kids with ADHD, the regions in which this delay was most prominent was in brain centers responsible for action and attention."

The study did have some limitations. The researchers were not able to study whether medications for ADHD might have had an effect on brain development, nor did they have enough participants to see if there were differences between boys and girls.

And, although the study showed an association, it did not prove a cause-and-effect linkage.

"This certainly is not the whole story of ADHD, but a delay in this structure of the cortex might be part of the story of ADHD," Shaw said.

Explore further: Brain development is delayed in attention-deficit/hyperactivity disorder

More information: The National Institute of Mental Health has more on ADHD.

Related Stories

Brain development is delayed in attention-deficit/hyperactivity disorder

July 30, 2012
Is attention-deficit/hyperactivity disorder (ADHD) due to a delay in brain development or the result of complete deviation from typical development? In the current issue of Biological Psychiatry, Dr. Philip Shaw and colleagues ...

Study of preschoolers with ADHD detects brain differences linked to symptoms

June 9, 2011
In a study published today in the Clinical Neuropsychologist (e-publication ahead of print), researchers from the Kennedy Krieger Institute found differences in the brain development of preschool children with symptoms of ...

Mutant gene linked to ADHD

April 18, 2011
(PhysOrg.com) -- In a recent study published in Nature Medicine, Dr. Eunjin Kim from the Korea Advanced Institute of Science and Technology uncovers a genetic fault that triples the chances of a child having ADHD (Attention ...

Recommended for you

Babies can learn that hard work pays off

September 21, 2017
If at first you don't succeed, try, try again. A new study from MIT reveals that babies as young as 15 months can learn to follow this advice. The researchers found that babies who watched an adult struggle at two different ...

Study links brain inflammation to suicidal thinking in depression

September 21, 2017
Patients with major depressive disorder (MDD) have increased brain levels of a marker of microglial activation, a sign of inflammation, according to a new study in Biological Psychiatry by researchers at the University of ...

Oxytocin turns up the volume of your social environment

September 20, 2017
Before you shop for the "cuddle" hormone oxytocin to relieve stress and enhance your social life, read this: a new study from the University of California, Davis, suggests that sometimes, blocking the action of oxytocin in ...

Researchers develop new tool to assess individual's level of wisdom

September 20, 2017
Researchers at University of San Diego School of Medicine have developed a new tool called the San Diego Wisdom Scale (SD-WISE) to assess an individual's level of wisdom, based upon a conceptualization of wisdom as a trait ...

Alcohol use affects levels of cholesterol regulator through epigenetics

September 20, 2017
In an analysis of the epigenomes of people and mice, researchers at Johns Hopkins Medicine and the National Institutes of Health report that drinking alcohol may induce changes to a cholesterol-regulating gene.

Self-control may not diminish throughout the day

September 20, 2017
After a long day of work and carefully watching what you eat, you might expect your self-control to slip a little by kicking back and cracking open a bag of potato chips.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.