Zack, aged 7 years, has always had trouble settling down. He is easily bored and distracted. In school, he cannot stay in his seat for very long and he frequently does not follow instructions. He is constantly fidgeting or staring into space. Zack has poor social skills and may overreact when someone accidentally bumps into him or uses one of his toys. At home, he chatters constantly and rarely settles down to do a quiet activity, such as reading a book.
Symptoms such as Zack’s are c ommon among 7-year-olds, and particularly among boys. But what do the symptoms mean? Does Zack simply have a lot of energy and a short attention span? Boys mature more slowly than girls at this age, and perhaps Zack will catch up in the next few years. One possibility is for the parents and teachers to work with Zack to help him be more attentive, to put up with the behavior, and to wait it out.
But many parents, often on the advice of the child’s teacher, take their children to a psychologist for diagnosis. If Zack were taken for testing today, it is very likely that he would be diagnosed with a psychological disorder known asattention-deficit/hyperactivity disorder (ADHD). ADHD is a developmental behavior disorder characterized byproblems with focus, difficulty maintaining attention, and inabilityto concentrate, in which symptoms start before7 years of age(American Psychiatric Association, 2000; National Institute of Mental Health, 2010). 1 Although it is usually first diagnosed in childhood, ADHD can remain problematic in adults, and up to 7% of college students are diagnosed with it (Weyandt & DuPaul, 2006). 2 In adults the symptoms of ADHD include forgetfulness, difficulty paying attention to details, procrastination, disorganized work habits, and not listening to others. ADHD is about 70% more likely to occur in males than in females (Kessler, Chiu, Demler, & Walters, 2005), 3 and is often comorbid with other behavioral and conduct disorders.
The diagnosis of ADHD has quadrupled over the past 20 years such that it is now diagnosed in about 1 out of every 20 American children and is the most common psychological disorder among children in the world (Olfson, Gameroff, Marcus, & Jensen, 2003). 4 ADHD is also being diagnosed much more frequently in adolescents and adults (Barkley, 1998). 5 You might wonder what this all means. Are the increases in the diagnosis of ADHD due to the fact that today’s children and adolescents are actually more distracted and hyperactive than their parents were, due to a greater awareness of ADHD among teachers and parents, or due to psychologists and psychiatrists’ tendency to overdiagnose the problem? Perhaps drug companies are also involved, because ADHD is often treated with prescription medications, including stimulants such as Ritalin.
Although skeptics argue that ADHD is overdiagnosed and is a handy excuse for behavioral problems, most psychologists believe that ADHD is a real disorder that is caused by a combination of genetic and environmental factors. Twin studies have found that ADHD is heritable (National Institute of Mental Health, 2008), 6 and neuroimaging studies have found that people with ADHD may have structural differences in areas of the brain that influence self- control and attention (Seidman, Valera, & Makris, 2005). 7 Other studies have also pointed to environmental factors, such as mothers’ smoking and drinking alcohol during pregnancy and the consumption of lead and food additives by those who are affected (Braun, Kahn, Froehlich, Auinger, & Lanphear, 2006; Linnet et al., 2003; McCann et al., 2007). 8 Social factors, such as family stress and poverty, also contribute to ADHD (Burt, Krueger, McGue, & Iacono, 2001). 9