ADHD Brain Size

ADHD is one of the most common psychiatric conditions in children. I found studies that children and teens with ADHD have slightly smaller brains (as shown in the picture above) than others without the disorder.This shows us a lot more about ADHD children and teens other than the actual brain size though.

One study was a ten year study from 1991-2001 that was funded by and conducted at The National Institute of Mental Health.
In this study MRI's were used to look 152 patients ages 5-18 having ADHD, 139 patients ages 5-18 who don't have ADHD. This also compared ADHD patients who were and were not on medication.

First, the study showed that hyperactivity is associated with a 3-4% decrease in volume throughout the whole brain and also that the smaller the brain the worse their symptoms were. Researchers have said that it seem that it appears the brains of ADHD children develop at a normal pace but, never fully catch up in the size brain of other kids without the disorder. Why is not truly yet known, however, they also said that these smaller brain size does NOT mean less intelligent. 

Next, they were able to find that the smaller brain volume doesn't appear to be related to drugs used to treat ADHD such as methylphenidate. So, in other words, the medication isn't doing this.

Finally, this study was able to let parents rest more assure of their parenting and provided environment. By this I mean there are a lot of people blame hyperactivity on the parenting or blame ADHD on environmental factors such as lead paint. The study showed that hyperactivity it a biological in origin and not from bad parenting or environmental.


I found these studies to be fascinating! And wanted to share what I have learned with my readers so I hope you have enjoyed learning this too. Now remember, in no way does this mean if you have an ADHD child that they are not as intelligent as others.

~S Overly

Resources: CBS News, Psych News,