***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: CONTEXT Attention-deficit/hyperactivity disorder ( ADHD ) is a highly prevalent and impairing psychiatric disorder that affects both children and adults . There are Food and Drug Administration-approved stimulant and nonstimulant medications for treating ADHD ; however , little is known about the mechanisms by which these different treatments exert their therapeutic effects . OBJECTIVE To contrast changes in brain activation related to symptomatic improvement with use of the stimulant methylpheni date hydrochloride vs the nonstimulant atomoxetine hydrochloride . DESIGN Functional magnetic resonance imaging before and after 6 to 8 weeks of treatment with methylpheni date ( n = 18 ) or atomoxetine ( n = 18 ) using a parallel-groups design . SETTING Specialized ADHD clinical research program at Mount Sinai School of Medicine , New York , New York . PARTICIPANTS Thirty-six youth with ADHD ( mean [ SD ] age , 11.2 [ 2.7 ] years ; 27 boys ) recruited from r and omized clinical trials . MAIN OUTCOME MEASURES Changes in brain activation during a go/no-go test of response inhibition and investigator-completed ratings on the ADHD Rating Scale-IV-Parent Version . RESULTS Treatment with methylpheni date vs atomoxetine was associated with comparable improvements in both response inhibition on the go/no-go test and mean ( SD ) improvements in ratings of ADHD symptoms ( 55 % [ 30 % ] vs 57 % [ 25 % ] ) . Improvement in ADHD symptoms was associated with common reductions in bilateral motor cortex activation for both treatments . Symptomatic improvement was also differentially related to gains in task-related activation for atomoxetine and reductions in activation for methylpheni date in the right inferior frontal gyrus , left anterior cingulate/supplementary motor area , and bilateral posterior cingulate cortex . These findings were not attributable to baseline differences in activation . CONCLUSIONS Treatment with methylpheni date and atomoxetine produces symptomatic improvement via both common and divergent neurophysiologic actions in frontoparietal regions that have been implicated in the pathophysiology of ADHD . These results represent a first step in delineating the neurobiological basis of differential response to stimulant and nonstimulant medications for ADHD This study examined effects of reward and response costs on the ability of 19 attention-deficit hyperactivity disorder ( ADHD ) and 17 control children to inhibit responding . Children were tested under 4 reinforcement conditions on a go/no-go learning task developed by J. P. Newman , C. S. Widom , and S. Nathan ( 1985 ) . Two conditions involved both reward and response costs . 1 response costs only , and 1 reward only .  ADHD children made more commission errors than controls across the 4 conditions . Analyses of learning curves indicated that group differences became larger on later trials . Thus , impaired inhibition was more generalized in ADHD children than in the psychopaths and extraverts studied by Newman and colleagues , and it became most evident when the children were required to improve learning across trials A disturbed functioning of the prefrontal cortex , the anterior cingulate cortex , and an accordingly reduced P300 presumably underlies executive function deficits of children with attention deficit hyperactivity disorder ( ADHD ) . Using a combined classification and Go/NoGo task paradigm , the present study investigated whether medication with methylpheni date ( MPH ) modulates the P300 as measured by a high-density electroencephalogram ( EEG ) and facilitates response inhibition in children with ADHD . Further , effects of MPH were compared with effects of self-regulation by if-then plans ( Gollwitzer in Am Psychol 54 : 493–503 , 1999 ) . MPH as well as if-then plans modulated the P300 and improved inhibition of an unwanted response on a Go/NoGo task to the same level observed in children without ADHD . Importantly , self-regulation strategies might be a valuable alternative to medication with MPH in children with ADHD The go-no go test requires a subject to emit a simple motor response to one cue while inhibiting the response in the presence of another cue . This test has been effective in demonstrating impulsivity ( elevated commission error rate ) in children with attention deficit disorder ( ADD ) . In this study , we examined the effects on go-no go test performance of two doses of methylpheni date ( 0.15 mg/kg and 0.3 mg/kg ) administered in double-blind placebo-controlled fashion to children with ADD . Our results indicate that even modest doses of methylpheni date improve the go-no go performance of these children by decreasing their tendency to make impulsive commission errors . Thus the test is sensitive to the effects of methylpheni date and can be used to monitor a response to therapy . ( J Child Neurol 1991 ; 6(Suppl):S126-S129 ) 
    Output:
    
Results indicate that deficits in withholding are insufficiently sensitive or specific to be used individually as a diagnostic measure or biomarker in most disorders