What Exactly Are the Benefits of Stimulants for ADHD?

Stimulant drugs (methylphenidate and amphetamine) have been used successfully for decades to improve the behavioral impairments of hyperactivity, impulsivity, and inattention in children diagnosed with attention-deficit/hyperactivity disorder (ADHD). A voluminous literature supports the benefits of stimulants for improv-ing classroom manageability and increasing attention and academic productivity in children. Nevertheless, academic underachievement remains a significant prob-lem in ADHD-diagnosed children. With the relatively recent understanding that ADHD persists into adulthood comes the recognition of continu-ing adverse academic, occupational, and interpersonal consequences. Longitudinal studies have concluded that although the symptom of hyperactivity decreases in adulthood and impulsivity may be less severe, significant impairment remains (Ingram, Hechtman, & Morgenstern, 1999). This is the case in spite of increasing use, both licit and illicit, of stimulant medications in adolescents and young adults. Given their well-established benefit for increasing attention and concentration, it seems counterintuitive that ADHD medications are not more effective in improving academic and occupational attain-ment. It is time to address this question and clarify the cognitive effects, as opposed to the activating, arousing, and energizing actions of these drugs. The prevalence of adult ADHD (in the United States) was recently found to be 4.4 % (Kessler et al., 2006) and follow-up studies of ADHD-diagnosed children report anywhere from 35 % to 80 % of cases will persist into adolescence with eventually 49 % to 66 % of these adults still meeting diagnostic criteria. Compared to adults who do not have ADHD, adults with ADHD reportedly have more social and marital difficulties and achieve less in their careers and in academia, despite having normal intellectual abilities (Spencer, Biederman, & Mick, 2007; Wilens, 2003). Among the impairments associated with ADHD, lack of academic achievement has been studied intensively