Perri Klass, M.D. wrote an article for The Times that summarizes the current science regarding ADHD.  It is entitled "Untangling the Myths about Attention Disorder."  She starts by contradicting the theories that today's world  breeds more problems with attention that are then diagnosed as ADHD and she rejects the use of ADHD as a metaphor for functioning in that world. She goes on to state that ADHD is a true disorder that goes beyond excessive multitasking.  In support of this premise, she references the first medical journal description of ADHD (although it wasn't called that) in 1905 and an 1845 poem entitled "Fidgety Philip" which described the disorder in rhyme.  She also refers to the imaging studies which have illustrated anatomic differences between children with ADHD and those without as well as the functional studies that show decreased brain activity in areas which control attention that can be corrected with stimulant medication.  What was most interesting to me was her discussion with Dr. Maximillian Muenke, the head of the medical genetics branch of the National Human Genome Research Institute.  His group has identified a specific gene associated with ADHD in some families that also seems to signal a good response to stimulant medication.  He predicted that in the future, genetic analysis might be able to indicate which patients with ADHD would respond to which medications or behavioral therapies.