Impulsivity is a central component of attention-deficit/hyperactivity disorder (ADHD). Delay discounting, or a preference for smaller, immediate rewards over larger, delayed rewards is considered an important aspect of impulsivity, and delay-related impulsivity has been emphasized in etiological models of ADHD. The current study examined whether stimulant medication, an effective treatment for ADHD, reduces discounting of delayed experiential and hypothetical rewards among 49 children (age 9-12 years) with ADHD. Following a practice day, participants completed a 3-day double-blind placebo-controlled acute medication assessment. Active doses were long-acting methylphenidate (Concerta), with the nearest equivalents of 0.3 and 0.6 mg/kg TID immediate-release methylphenidate. On each testing day, participants completed experiential (real-world money in real time) and hypothetical discounting tasks. Relative to placebo, methylphenidate reduced discounting of delayed experiential rewards, but not hypothetical rewards. Broadly consistent with etiological models that emphasize delay-related impulsivity among children with ADHD, these findings provide initial evidence that stimulant medication reduces delay discounting among those with the disorder. The present results also draw attention to task parameters that may influence the sensitivity of various delay discounting measures to medication effects.Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous disorder characterized by developmentally inappropriate and impairing levels of inattention and/or hyperactivity and impulsivity (see American Psychiatric Association, 2000;Swanson et al., 1998). Etiological models of ADHD implicate cognitive and motivational processes, and an integration of these processes as in the dual-pathway model of ADHD (Sonuga-Barke, 2002, 2005. Within this model, impulsive behavior is characterized in part as a rational choice to avoid delay because it is experienced as aversive. Delay aversion is considered an important pathway in the development of ADHD, along with executive function deficits such as inhibitory control . The delay aversion hypothesis emphasizes the negative motivational and emotional significance of delay for children with ADHD as an expression of a broader motivational style, which results in a preference for immediate over delayed rewards (Sonuga-Barke, Sergeant, Nigg, & Willcutt,

Preclinical research and learning theory suggest that a longer duration of varenicline treatment prior to the target quit date (TQD) should reduce smoking rates before cessation and improve abstinence outcomes. A double-blind RCT tested this hypothesis among 60 smokers randomized to either Extended (4 weeks of pre-TQD varenicline) or standard run-in (3 weeks of placebo, 1 week of pre-TQD varenicline); everyone received 11 weeks of post-TQD varenicline and brief counseling. During the pre-quit run-in, the reduction in smoking rates was greater among the Extended group (42% vs. 24%, p<0.01) and this effect was greater among women (57% vs. 26%, p=0.001). Continuous abstinence during the final four weeks of treatment was enhanced among women in the Extended group (67% vs. 35%). While these data suggest that extending pre-quit varenicline reduces smoking during the pre-quit period and may further enhance cessation rates, confirmatory evidence is needed from larger clinical trials. Trial Registration: www.clinicaltrials.gov identifier: NCT00835900

Introduction Attention deficit/hyperactivity disorder (ADHD) is associated with health risks in adolescence which includes the potential for smoking cigarettes, early smoking initiation, and rapid progression to daily smoking. Much less is known, however, about prognostically-relevant smoking behaviors among individuals with childhood ADHD. Further research in this area is important for identifying individuals at pronounced risk for nicotine addiction, and for developing effective interventions for this population. Method This study examined initiation of cigarette smoking, progression to regular smoking, quantity of use, indicators of tobacco dependence, and quit rates among adolescents and young adults with (n=364) and without (n=240) childhood ADHD. Results Individuals with, versus without, ADHD histories were significantly more likely to become daily smokers independent of conduct disorder. They were also more likely to initiate smoking at younger ages and to progress to regular smoking more quickly. There were no significant group differences in cigarettes smoked per day, Fagerstrom Test of Nicotine Dependence or Nicotine Dependence Syndrome Scale scores or in smoking within 30 min of waking. However, smokers with ADHD reported more intense withdrawal and craving during periods of abstinence than nonADHD smokers. There were no significant group differences in number of quit attempts. Lastly, there were no significant differences among symptom persisters and desisters in daily smoking and amount. Conclusions Individuals with ADHD histories are at high risk for persistent smoking given their early onset, rapid course, and abstinence characteristics. Smoking cessation programs may need to be adapted or otherwise intensified for those with ADHD.