Background and History , How common is ADD?

ADD was first identified and studied in the early 1900's, although it wasn't called ADD back then. After World War I, researchers noted that children who had contracted encephalitis displayed a high incidence of hyperactivity, impulsivity, and conduct disorders. And in the 1940's, some soldiers who had experienced brain injuries were found to have behavioral disorders.It seemed clear that brain damage could cause hyperactivity. Other forms of brain insult have since been identified as causes of hyperactivity, including exposure to lead and other environmental toxins, as well as fetal exposure to drugs and alcohol.




Once brain damage was identified as a cause of hyperactivity in certain patients, researchers assumed that all hyperactivity was caused by brain damage, even when no brain damage could be identified. That's why ADD wasonce called "minimal brain dysfunction." This is an important point to understand. It is because of this early association of brain injury and hyperactivity that ADD traits are still assumed by many to reflect a brain disorder. Researchers made a giant leap in logic: Because brain injury can lead to hyperactivity, they believed that all hyperactivity was caused by brain injury. We now know this is not true. In fact, hyperactivity is also associated with giftedness, but obviously we cannot say that all hyperactive children are gifted any more than we can say all hyperactive children have suffered brain injury.

More recent studies have shown that ADD is largely genetic. That is, it runs in families. This has lead some ADD researchers, notably Russell Barkley, to assume that our population is experiencing large scale random genetic mutations, a rather ridiculous notion for anyone familiar with population genetics. Anytime more than one percent of the population carries a gene,geneticists rule out random mutations under the belief that the gene has been actively selected for. For example, the gene-based disease sickle cell anemia has been found to help a population by providing resistance to malaria.

In the 1990's a growing number of ADD experts began to view ADD not so much as a disorder, but instead a natural condition which leaves ADDers at a disadvantage in some common modern settings, and many positive attributes became associated with ADD, such as creativity, enthusiasm and entrepreneurial tendencies. This is probably due in part to the ever expanding world of ADDers. A few decades ago only the most dysfunctional hyperactive kids were identified as "disordered" and these kids were more likely to suffer from actual brain injury. Today, the diagnostic criteria are so broad that millions of children in the U.S. are getting the label. Any underachiever who doesn't seem to pay attention in school or who has trouble handing in finished homework is fair game for a diagnosis. I spoke to one teenager who was diagnosed ADD even though her grade point average had never been below a 3.85 (taking Ritalin allowed her to achieve a 4.0). I also spoke to a psychiatrist who routinely prescribed Ritalin to "C" students in an effort to improve their grade point average.




The figure for ADD is typically given as 3-5 percent of the population. The real figure is unknown and estimates vary between 1 and 20 percent or even more. This is largely because the diagnostic criteria are so subjective: What is considered "clinically significant impairment" to one person might seem more like normal childhood behavior to someone else. For example, in one English survey, only 0.09 percent of the children were found to be ADD. But in an Israeli study, 28 percent of children were rated hyperactive by their teachers. And in one U.S. study, teachers rated 50 percent of boys as restless, 43 percent of boys as having "short attention spans" and 43 percent of boys as "inattentive to what others say."

Diagnoses and medication rates can vary greatly within the U.S. Gretchen Lefever, a pediatric psychologist who became concerned when she was suddenly inundated with ADD referrals, studied 30,000 grade-school students in two Virginia school districts. Her findings, which were published in "The American Journal of Public Health", showed that 17% of white boys in the region were given medication for ADD while at school. Other rates were 9% for African-America^{n boys, 7% for white girls, and 3% for African-American girls.}