Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental syndromes, with recent data suggesting prevalence rates in school-aged children between 8–10% (American Academy of Pediatrics & Subcommittee on Attention-Deficit/Hyperactivity Disorder, 2001; Barbaresi et al., 2002; Katusic et al., 2002; Leibson et al., 2001). Symptom onset is by the age of seven, with symptoms often evident between the ages of three to five years. The accurate diagnosis and effective treatment of ADHD in children can be critical to their academic, social, and interpersonal functioning. However, this is complicated by high rates of comorbid disorders in children with ADHD, including learning disabilities. The role of behavioral and neuropsychological assessment in diagnosis and treatment planning and effective treatment interventions will be discussed in this chapter. Furthermore, cognitive theories of ADHD and neuropsychological research, along with implications for clinical practice and future research will also be discussed.
The diagnosis of ADHD
ADHD is primarily characterized by two groups of core symptoms: (1) inattention and (2) hyperactive and impulsive behaviors. Currently, the DSM-IV-TR (APA, 2000) categorizes ADHD into three major subtypes: (1) Predominantly Inattentive Type (ADHD-I); (2) Predominantly Hyperactive/Impulsive Type (ADHD-H/I); and (3) Combined Type (ADHD-C), with the latter being the most common. Symptoms include short attention span, distractibility, forgetfulness, disorganization, restlessness, hyperactivity, impulsive responding and talkativeness. Overall, the male-to-female ratio for diagnosis is approximately 2:1 in community surveys (Cohen et al., 1999; Fergusson et al., 1993; Szatmari, Offord & Boyle, 1989).