Neuroimaging of Smokers With and Without Attention Deficit Hyperactivity Disorder (ADHD)
Condition: Smoking; ADHD
MeSH terms: Attention Deficit Disorder with Hyperactivity
Study type: Observational

Summary: 
      The purpose of this study is to evaluate how nicotine, withdrawal from nicotine, and
      methylphenidate (a drug used for the treatment of ADHD) affect the brain of smokers with and
      without ADHD while doing tasks in an functional Magnetic Resonance Imaging scanner.

      Study Hypotheses:

        1. compared to non-ADHD smokers, smokers with ADHD will exhibit greater abstinence-induced
           decrements in response inhibition performance and reward and greater concomitant
           disruptions of brain activity

        2. administration of MPH to abstinent smokers will ameliorate response inhibition
           performance and reward deficits and task-related brain activation and this effect will
           be greater among ADHD smokers

        3. genetic markers of dopamine neurotransmission will moderate abstinence- and MPH -
           induced changes in task-related brain activation across tasks.
    

Detailed description: 
      Individuals diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) smoke more than
      the general population, initiate use at a younger age, and report more difficulty trying to
      quit. The overarching goal of the present application is to use neuroimaging,
      neuropharmacological and molecular genetic techniques to study the neurobiological basis of
      abstinence-induced deficits in response inhibition in ADHD and non-ADHD smokers. Twenty
      smokers with ADHD and 20 smokers without ADHD will undergo imaging during a Go/No-Go task
      under the following conditions: 1) smoking as usual, 2) 24 hr smoking abstinence, and 3) 24
      hr smoking abstinence + methylphenidate (MPH). We hypothesize that compared to smoking as
      usual, 24 hr smoking abstinence will result in decrements in response inhibition and
      disruption of task-related brain activation. These effects will be greater in ADHD as
      compared to non-ADHD smokers. We further hypothesize that MPH administration during
      abstinence will restore performance and brain indices of response inhibition and that the
      magnitude of the effect of MPH will be greater among smokers with ADHD. In addition to the
      above aims, we will preliminarily evaluate the moderating effects of the dopamine receptor D4
      7-repeat allele on task-related brain activation following smoking abstinence and MPH
      administration.

      During the study, 101 subjects signed consents and 38 subjects completed the study.
    

Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        120 voluntary participants to yield 40 Adult Regular Smokers, including 20 diagnosed with
        ADHD and 20 comparison controls.
      
Biospecimen description: 
      Samples With DNA
    
Keywords: Smoking; ADHD; Nicotine; Methylphenidate; function Magnetic Resonance Imaging; Neurobiological basis of abstinence-induced deficits in response inhibition