Driven To Distraction
Adults are as scatterbrained as kids. And the disorder may be rooted in basic biology
No one knows for sure what causes ADD, but it is generally thought to be a complex alchemy of genetics, environment, and biochemistry. "Some people can have a stronger genetic load to their condition, some a stronger environmental load, and for others, obstetric complications at birth could contribute to the disorder," says Stephen Faraone, a clinical professor of psychiatry at Harvard Medical School. Those obstetric complications include the consequences of mothers' smoking: Studies of pregnant rats and mice, for example, have shown a direct association between chronic exposure to nicotine and hyperactive baby mice and rats.
Pam Rossi never smoked, but she will always wonder if the high forceps delivery 31 years ago of Eric Johnson, the oldest of her three sons, could have been responsible for his subsequent ADD. The birth was difficult, and he was starved for oxygen and bruised around the neck. Rossi, a slender and chic interior designer, pulls out a worn baby book from 1972 when Eric was born. He was 9 pounds, 8 ounces at birth. At the 6- month milestone, Pam Rossi wrote: "Eric never sleeps." In retrospect, that observation was diagnostic of early ADD. While Eric was clearly a brilliant child, reading early and voraciously, with enormous artistic talent, he foundered in school. Rossi took him to various specialists, all of whom had different notions of the problem. Because Eric was inattentive, rather than hyperactive, and because understanding of the disorder was just beginning, the specialists who saw Eric did not diagnose him properly. All the difficulties began to take their toll, and when Eric was in ninth grade, his jaunty intellectual self-confidence began to be replaced by creeping self-doubt. He knew he was intelligent, but he still couldn't perform. His ninth-grade teacher suggested to Rossi that he switch to vocational education classes. "You can't do this to him," Rossi said to the teacher. "This is a child who reads, who loves academics." She took Eric for another evaluation and finally received the diagnosis and a prescription for 10 milligrams of the stimulant medication Dexedrine. His performance at school was transformed, and his art became somehow more disciplined.
Russell Barkley, a professor at the Medical University of South Carolina and author of numerous works on ADHD, describes the disorder as "a developmental failure in brain circuitry that underlies inhibition and self-control. This loss of self-control in turn impairs other important brain functions crucial for maintaining attention." Many studies suggest that there is reduced frontal lobe activity in ADD, which may in turn be triggered by decreased activity in the basal ganglia, a deeper part of the forebrain that generates two important neurotransmitters called dopamine and norepinephrine. "Most people don't have any clue about how complicated this disorder is," says Thomas Brown, the associate director of the Yale Clinic for Attention and Related Disorders. As the story of Eric Johnson illustrates, the disorder often has nothing to do with hyperactivity or with intelligence; it can afflict both a genius and a person who is functioning at a 3-year-old level. "Everyone with this disorder has a few domains where they function perfectly well. So it looks like a problem of willpower, but in fact it is not willpower; it is fundamentally a chemical problem," Brown says. Increasingly, brain imaging studies are also pointing to the cerebellum, which has an important role in cognitive processing, coordination, and movement.