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CONTEXT Attention-deficit/hyperactivity disorder (ADHD)--characterized by symptoms of inattention and hyperactivity-impulsivity--is the most prevalent childhood psychiatric disorder that frequently persists into adulthood, and there is increasing evidence of reward-motivation deficits in this disorder. OBJECTIVE To evaluate biological bases that might(More)
Multiple theories of Attention-Deficit/Hyper-activity Disorder (ADHD) have been proposed, but one that has stood the test of time is the dopamine deficit theory. We review the narrow literature from recent brain imaging and molecular genetic studies that has improved our understanding of the role of dopamine in manifestation of symptoms of ADHD, performance(More)
OBJECTIVES To develop a categorical outcome measure related to clinical decisions and to perform secondary analyses to supplement the primary analyses of the NIMH Collaborative Multisite Multimodal Treatment Study of Children With Attention-Deficit/Hyperactivity Disorder (MTA). METHOD End-of-treatment status was summarized by averaging the parent and(More)
When used to treat children with Attention Deficit Hyperactivity Disorder, methylphenidate (MPH) acts primarily by blocking the dopamine (DA) transporter (DAT) and increasing extracellular DA in the striatum. This is strikingly similar to the mechanism of action of cocaine, a primary stimulant drug of abuse. When administered intravenously, MPH like cocaine(More)
Dopamine is believed to play a major role in the manifestation of attention deficit hyperactivity disorder (ADHD), which affects 3-6% of school-age children and shows evidence of familiarity. The dopamine D4 receptor, which is preferentially distributed in cortical and limbic regions of the brain, is currently of major interest because of the high degree of(More)
Loss of control over drug taking is considered a hallmark of addiction and is critical in relapse. Dysfunction of frontal brain regions involved with inhibitory control may underlie this behavior. We evaluated whether addicted subjects when instructed to purposefully control their craving responses to drug-conditioned stimuli can inhibit limbic brain(More)
OBJECTIVE Results of the NIMH Collaborative Multisite Multimodal Treatment Study of Children With Attention-Deficit/Hyperactivity Disorder (MTA) were analyzed to determine whether a double-blind, placebo-controlled methylphenidate (MPH) titration trial identified the best MPH dose for each child with attention-deficit/hyperactivity disorder (ADHD). METHOD(More)
Imaging studies have provided new insights on the role of dopamine (DA) in drug abuse and addiction in the human brain. These studies have shown that the reinforcing effects of drugs of abuse in human beings are contingent not just on DA increases per se in the striatum (including the nucleus accumbens) but on the rate of DA increases. The faster the(More)
An association of the dopamine receptor D4 (DRD4) gene located on chromosome 11p15.5 and attention deficit/hyperactivity disorder (ADHD) has been demonstrated and replicated by multiple investigators. A specific allele [the 7-repeat of a 48-bp variable number of tandem repeats (VNTR) in exon 3] has been proposed as an etiological factor in attentional(More)
CONTEXT Attention-deficit/hyperactivity disorder (ADHD) is the most prevalent psychiatric disorder of childhood. There is considerable evidence that brain dopamine is involved in ADHD, but it is unclear whether dopamine activity is enhanced or depressed. OBJECTIVE To test the hypotheses that striatal dopamine activity is depressed in ADHD and that this(More)