Are Motivation Deficits Underestimated in Patients With ADHD? A Review of the Literature

Abstract

Attention-deficit/hyperactivity disorder (ADHD) is characterized by impaired inhibition, inattention, and altered sensitivity to rewards. Behavioral studies support the presence of motivational disturbances as a distinct component of ADHD. Functional magnetic resonance imaging is a technology now used to research the brain circuitry underlying motivation. These studies indicate that individuals with ADHD exhibit hyporesponsitivity of the dopamine neurons in the ventral and dorsal striata in response to rewarding stimuli. Our article reviews the research examining interactions between external motivation and the responses of individuals with ADHD, from both neurobiologic and clinical perspectives. A PubMed search of studies written in English between 2000 and 2012 with keywords ADHD and motivation was conducted. Motivational processes are examined using behavioral and neurobiologic paradigms. Behavioral studies show altered processing of reinforcement and incentives in children with ADHD. These children respond more impulsively to rewards and choose small, immediate rewards over larger, delayed incentives. Interestingly, a high intensity of reinforcement is effective in improving task performance in children with ADHD. Pharmacotherapy may also improve task persistence in these children. Previous studies suggest that a clinical approach using interventions to improve motivational processes in patients with ADHD may improve outcomes as children with ADHD transition into adolescence and adulthood.