Expert: Dr Billy Levin - 2/23/2009

Question
Dr. Levin,

I read a Q&A in which you responded that "There is a vast difference between ADHD and Autism, although they do have some overlapping symptoms."  Can you explain the difference or at least give me a reference to a web page, research paper, or book that explain it to me?

I keep hearing that ADHD is actually a part of Autism.  I'm very confused, because I also hear the opposite.

Answer
The most important difference is that the treatment of ADHD with stimulants is very successful while ASD responds very poorly if at all to stimulants. There is no known effective medical treatment for ASD. Many ADHD people will lead a normal or very close to normal life and about 60% will outgrow the problem.
ASD will respond to certain therapies to a degree but  will always be a problem. In ASD the IQ is usually on the very low to retarded range with exceptions like the Asperger syndrome where the IQ is almost normal. In ADHD the IQ is almost always nornal to high.
In ASD speech is usually severely affected , but not so with ADHD.
There appears to a clear neurological explanation for ADHD. It is usually an inherited dysfunction where the tendency is for the right brain to develope too too fast while the left shows clear signs of immaturity. This is reflected in the frequent finding that the verbal IQ  is lower than the non verbal IQ. ASD is an abnormality.
In ADHD the key features are hyperactivity, inattention and distractability. In ASD there is very poor speech, no real social or eye contact and often intensense perseveration while playing with piece of paper for example.  
Do a Google search for ADHD and Autism for more information.