1. ADHD Symptoms in Children Slideshow Pictures
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3. ADHD in Adults Slideshow Pictures

Medical Author:

John Mersch, MD, FAAP

John Mersch, MD, FAAP

Dr. Mersch received his Bachelor of Arts degree from the University of California, San Diego, and prior to entering the University Of Southern California School Of Medicine, was a graduate student (attaining PhD candidate status) in Experimental Pathology at USC. He attended internship and residency at Children's Hospital Los Angeles.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Research has shown that ADHD does seem to cluster in families. Several investigations have demonstrated that children who have ADHD usually have a least one close relative (child or adult) who also has ADHD. At least one-third of all fathers who have ADHD will produce a child with ADHD. With the newer realization that adults may also experience ADHD symptoms, it is not unheard of to have a parent's "problem at my job" be credited to ADHD -- often at the same time that their child's diagnosis is being established! Lastly, several studies have demonstrated a number of genes that may reflect a role in altered brain neurochemistry that provides a physiologic basis for this disorder and inheritance pattern.

No one knows for sure whether the prevalence of ADHD per se has risen, but it is very clear that the number of children identified with the disorder and who obtain treatment has risen over the past decade. Some of this increased identification and increased treatment-seeking is due in part to greater media interest, heightened consumer awareness, and the availability of effective treatments. Teachers are better trained to recognize the condition and suggest that the family seek help, especially in the more mild to moderate cases. The condition itself is so much more clearly defined and more concisely diagnosed now. The diagnosis of ADHD is also less of a social stigma than in the past. This more enlightened perspective reflects the understanding that ADHD is a biochemical disorder and not merely an "out of control child." As such, more parents are receptive to medical therapy for the condition rather than resorting to less effective home/school discipline techniques. Interestingly, the increase in prevalence of ADHD is not solely an American phenomenon but has been noted also in other countries. Whether the number of patients with ADHD has truly increased or rather our better recognition and acceptance of ADHD as a diagnosis has "increased" the number of patients remains to be further defined.

Neuroimaging research has shown that the brains of children with ADHD differ fairly consistently from those of children without the disorder in that several brain regions and structures tend to be smaller. There is also a lack of expected symmetry between the right and left brain hemispheres. Overall, brain size is generally 5% smaller in affected children than children without ADHD. While this average difference is observed consistently, it is too small to be useful in making the diagnosis of ADHD in a particular individual. In addition, there appears to be a link between a person's ability to pay continued attention and measures that reflect brain activity. In people with ADHD, the brain areas that control attention appear to be less active, suggesting that a lower level of activity in some parts of the brain may be related to difficulties sustaining attention. It is important to reiterate that these laboratory observations are not yet sufficiently sensitive or specific enough to use to establish or confirm the diagnosis of ADHD or to monitor the effectiveness of treatment.

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