A longitudinal examination of neuropsychological and clinical functioning in boys with attention deficit hyperactivity disorder (ADHD): improvements in executive functioning do not explain clinical improvement. Executive function and attention deficit hyperactivity disorder: stimulant medication and better executive function performance in children. Mediators of Methylphenidate Effects on Math Performance in Children with Attention-Deficit Hyperactivity Disorder Modafinil Improves Cognition and Attentional Set Shifting in Patients with Chronic Schizophrenia Dissecting the attention deficit hyperactivity disorder (ADHD) phenotype: Sustained attention, response variability and spatial attentional asymmetries in relation to dopamine transporter (DAT1) genotype Effects of Methylphenidate on Impulsive Responding in Children With Attention-Deficit Hyperactivity Disorder Slow oscillating transcranial direct current stimulation during non-rapid eye movement sleep improves behavioral inhibition in attention-deficit/hyperactivity disorder A Pilot Twin Study of Psychological Measures of Attention Deficit Hyperactivity Disorder A context for normalizing impulsiveness at work for adults with attention deficit/hyperactivity disorder (combined type). A Randomized, Double-Blind, Sham-Controlled Trial of Transcranial Direct Current Stimulation in Attention-Deficit/Hyperactivity Disorder Responsiveness of children with attention deficit-hyperactivity disorder to reward and response cost: differential impact on performance and motivation. Effectiveness of a School-Based Multicomponent Program for the Treatment of Children with ADHD Measurement of the Effect of Physical Exercise on the Concentration of Individuals with ADHD Sex Differences in Effectiveness of Extended-Release Stimulant Medication among Adolescents with Attention-Deficit/Hyperactivity Disorder Effect of acute exercise on executive function in children with attention deficit hyperactivity disorder. Executive Impairment Determines ADHD Medication Response: Implications for Academic Achievement Executive functioning in children with attention-deficit/hyperactivity disorder: combined type with and without a stimulant medication history. Adult outcome of attention-deficit/hyperactivity disorder: a controlled 16-year follow-up study. Effects of methylphenidate on working memory functioning in children with attention deficit/hyperactivity disorder. Effects of OROS Methylphenidate on Academic, Behavioral, and Cognitive Tasks in Children 9 to 12 Years of Age With Attention-Deficit/Hyperactivity Disorder Motivational incentives and methylphenidate enhance electrophysiological correlates of error monitoring in children with attention deficit/hyperactivity disorder Methylphenidate and if-then plans are comparable in modulating the P300 and increasing response inhibition in children with ADHD Atomoxetine and stroop task performance in adult attention-deficit/hyperactivity disorder.
BACKGROUND Attention deficit hyperactivity disorder ( ADHD ) often , but not always , persists into adulthood . Investigations of the associations between clinical and biological markers of persistence can shed light on causal pathways . It has been proposed that compensatory improvements in executive neuropsychological functioning are associated with clinical improvements . This is the first study to test this hypothesis prospect ively . METHOD The clinical and neuropsychological functioning of 17 boys with ADHD ( mean age 10.45 years at time 1 ; 14.65 years at time 2 ) and 17 typically developing ( TYP ) boys ( mean age 10.39 years at time 1 ; 14.47 years at time 2 ) was tested on two occasions , 4 years apart . This was done using a battery of st and ardized neuropsychological tests that included tasks with high and low executive dem and s. RESULTS Clinical improvements were observed over time . Neuropsychological performance improvements were also evident , with ADHD boys developing with a similar pattern to TYP boys , but with a developmental lag . Whilst there was an association between reduced symptoms and superior performance at retest for one task with a high executive dem and ( spatial working memory ) , this was not seen with two further high executive dem and tasks [ Stockings of Cambridge and intra-dimensional extra-dimensional ( ID/ED ) set shifting ] . Also , there was no association between change in executive functioning and change in symptoms . Baseline performance on the ID/ED set-shifting task predicted better clinical outcome . Only change in performance on the low executive dem and delayed matching-to- sample task predicted better clinical outcome . CONCLUSIONS These data highlight the importance of longitudinal measurements of cognition , symptoms and treatment response over time in children and adolescents with ADHD BACKGROUND Executive function deficits have been reported repeatedly in children with Attention Deficit Hyperactivity Disorder ( ADHD ) .  Stimulant medication has been shown to be effective in improving cognitive performance on most executive function tasks , but neuropsychological tests of executive function in this population have yielded inconsistent results . Method ological limitations may explain these inconsistencies . This study aim ed to measure executive function in medicated and non-medicated children with ADHD by using a computerized battery , the Cambridge Neuropsychological Test Automated Battery ( CANTAB ) , which is sensitive to executive function deficits in older patients with frontostriatal neurological impairments . METHODS Executive function was assessed in 30 children with ADHD : 15 were stimulant medication naive and 15 were treated with stimulant medication .  These two groups were compared to 15 age , sex and IQ matched controls . RESULTS The unmedicated children with ADHD displayed specific cognitive impairments on executive function tasks of spatial short-term memory , spatial working memory , set-shifting ability and planning ability . Impairments were also seen on spatial recognition memory and delayed matching to sample , while pattern recognition memory remained intact . The medicated children with ADHD were not impaired on any of the above executive function tasks except for deficits in spatial recognition memory . CONCLUSIONS ADHD is associated with deficits in executive function .  Stimulant medication is associated with better executive function performance . Prospect i ve follow-up studies are required to examine these effects Objective : Stimulant medications , such as methylpheni date ( MPH ) , improve the academic performance of children with attention-deficit hyperactivity disorder ( ADHD ) . However , the mechanism by which MPH exerts an effect on academic performance is unclear . We examined MPH effects on math performance and investigated possible mediation of MPH effects by changes in time on-task , inhibitory control , selective attention , and reaction time variability . Methods : Children with ADHD aged 7 to 11 years ( N = 93 ) completed a timed math worksheet ( with problems tailored to each individual 's level of proficiency ) and 2 neuropsychological tasks ( Go/No-Go and Child Attention Network Test ) at baseline , then participated in a 4-week , r and omized , controlled , titration trial of MPH . Children were then r and omly assigned to their optimal MPH dose or placebo for 1 week ( administered double-blind ) and repeated the math and neuropsychological tasks ( posttest ) . Baseline and posttest videorecordings of children performing the math task were coded to assess time on-task . Results : Children taking MPH completed 23 more math problems at posttest compared to baseline , whereas the placebo group completed 24 fewer problems on posttest versus baseline , but the effects on math accuracy ( percent correct ) did not differ . Path analyses revealed that only change in time on-task was a significant mediator of MPH 's improvements in math productivity . Conclusions : MPH-derived  math productivity improvements may be explained in part by increased time spent on-task , rather than improvements in neurocognitive parameters , such as inhibitory control , selective attention , or reaction time variability Modafinil , a novel cognitive enhancer , selectively improves neuropsychological task performance in healthy volunteers and adult patients with attention deficit hyperactivity disorder ( ADHD ) . It has been argued that persistent cognitive deficits in patients with schizophrenia are responsible for the failure of many patients to rehabilitate socially even when psychotic symptoms are in remission . The present study examined the potential of modafinil as a cognitive enhancer in schizophrenia . Twenty chronic patients with a diagnosis of schizophrenia were entered into a double-blind , r and omized , placebo-controlled crossover study using a 200 mg dose of modafinil . Modafinil had some cognitive enhancing properties in schizophrenia similar to those observed in healthy adults and adult patients with ADHD . Improvement was seen on short-term verbal memory span , with trends towards improved visual memory and spatial planning . This was accompanied by slowed response latency on the spatial planning task . No effect on stop-signal performance was seen . Importantly , significant improvement in attentional set shifting was seen , despite no effect of modafinil on this task being seen in healthy volunteers or ADHD patients . Modafinil may have potential as an important therapy for cognitive impairment in patients with schizophrenia , particularly because of its beneficial effects on attentional set shifting ADHD is a childhood-onset behavioural disorder with a heterogeneous profile of neuropsychological impairment . Neuropsychological heterogeneity may , in part , reflect underlying genetic differences . Here we examined sustained attention , response variability and spatial attentional asymmetries in a sample of children and adolescents with ADHD ( n=22 ) in relation to dopamine transporter genotype ( DAT1 ) and also controls ( n=20 ) . Participants performed the sustained attention to response task ( SART ) ( testing sustained attention and response variability ) and the greyscales task ( a perceptual measure of attentional bias ) . The latter has previously been shown to yield a robust leftward attentional asymmetry in healthy subjects . The 10-repeat allele of the DAT1 gene has been associated with ADHD in a number of studies and appears to have biological significance . The ADHD group was sub-divided into those individuals with two copies of the " high-risk " 10-repeat allele ( high-risk DAT1 ) versus those with one or no copies of this allele ( low-risk DAT1 ) . The high-risk DAT1 ADHD group displayed greater response variability on the SART than either the low-risk DAT1 group or healthy controls , whereas the latter two groups did not differ . Further , the high-risk DAT1 group showed an attenuated spatial asymmetry , relative to the low-risk DAT1 ADHD group , who showed the typical leftward attentional asymmetry . Our results suggest that the 10-repeat DAT1 allele may mediate neuropsychological impairment in ADHD . The application of molecular genetics may help to define neuropsychological impaired subgroups of ADHD The present investigation examined the effects of methylpheni date on impulsivity in children with attention-deficit hyperactivity disorder ( ADHD ) . A task was design ed to measure empirically the ADHD child 's proclivity to blurt out incorrect answers before giving a final and /or correct response . Twenty-six ADHD children referred for double-blind placebo-controlled assessment of medication responsiveness and 14 non-ADHD controls were given a visual search word-matching task to assess impulsive responding . An analysis of covariance showed that ADHD children on methylpheni date made fewer impulsive errors than ADHD children on placebo . The control group made fewer impulsive errors than the ADHD children in the placebo condition , but the performance of the ADHD children on medication approximated the performance of the children without ADHD . These preliminary findings suggest that the word-matching task may be a useful tool for assessing impulsive responding and determining the benefits of stimulant medication on impulsivity . ( J Child Neurol 1993;8:157 - 163 ) Background : Behavioral inhibition , which is a later-developing executive function ( EF ) and anatomically located in prefrontal areas , is impaired in attention-deficit and hyperactivity disorder ( ADHD ) . While optimal EFs have been shown to depend on efficient sleep in healthy subjects , the impact of sleep problems , frequently reported in ADHD , remains elusive . Findings of macroscopic sleep changes in ADHD are inconsistent , but there is emerging evidence for distinct microscopic changes with a focus on prefrontal cortical regions and non-rapid eye movement ( non-REM ) slow-wave sleep . Recently , slow oscillations ( SO ) during non-REM sleep were found to be less functional and , as such , may be involved in sleep-dependent memory impairments in ADHD . Objective : By augmenting slow-wave power through bilateral , slow oscillating transcranial direct current stimulation ( so-tDCS , frequency = 0.75 Hz ) during non-REM sleep , we aim ed to improve daytime behavioral inhibition in children with ADHD . Methods : Fourteen boys ( 10–14 years ) diagnosed with ADHD were included . In a r and omized , double-blind , cross-over design , patients received so-tDCS either in the first or in the second experimental sleep night . Inhibition control was assessed with a visuomotor go/no-go task .  Intrinsic alertness was assessed with a simple stimulus response task . To control for visuomotor performance , motor memory was assessed with a finger sequence tapping task . Results : SO-power was enhanced during early non-REM sleep , accompanied by slowed reaction times and decreased st and ard deviations of reaction times , in the go/no-go task after so-tDCS . In contrast , intrinsic alertness , and motor memory performance were not improved by so-tDCS . Conclusion : Since behavioral inhibition but not intrinsic alertness or motor memory was improved by so-tDCS , our results suggest that lateral prefrontal slow oscillations during sleep might play a specific role for executive functioning in ADHD There has been much interest in the genetics of attention deficit hyperactivity disorder and molecular genetic studies are now underway . The success of genetic studies will depend on how well the phenotype is defined . Twin studies using parent and teacher rated question naires or interviews all appear to yield highly heritable measures . Nevertheless , there is evidence to suggest that parent measures are subject to rater bias . Consequently there has been much interest in obtaining more objective measures of related traits such as attention span and impulsiveness using , computerised neuropsychological tasks . However there have been few twin studies examining the genetic contribution to these neuropsychological measures . The present study aims to investigate whether performance on the  Matching Familiar Figures Test ( MFFT ) and Continuous Performance Task ( CPT )  is genetically influenced in childhood . 20 monozygotic ( MZ ) and 20 dizygotic ( DZ ) twin pairs were r and omly selected from the Greater Manchester Twin Register . Preliminary data suggest that MZ twins perform more similarly than DZ twins on the MFFT , but not the CPT . Future work needs to examine whether other neuropsychological measures commonly used in research on ADHD are genetically influenced using larger twin sample Impaired executive function and impulsiveness or intolerance to boredom in adult attention deficit/hyperactivity disorder ( ADHD ) are thought to compromise performance at work . Several task parameters help people with ADHD to perform better on computerized cognitive tasks , namely reduced response-to-stimulus interval , discriminative feedback , or a format resembling a videogame . However , still very little is known about how these context s might be helpful in a real work environment . We developed a computerized task resembling a fast-paced videogame with no response-to-stimulus interval and constant and diverse discriminative error feedback . The task included several measurements of high-order executive function ( planning , working memory , and prospect i ve memory ) formatted as a single multitask simulating occupational activities ( SOA ) . We also administered the Continuous Performance Test-II ( CPT-II ) , a very simple vigilance task without discriminative feedback and with long response-to-stimulus intervals . We tested 30 adults answering to DSM-IV criteria of ADHD ( combined type ) and 30 IQ-matched adults without ADHD . As has been reported many times , the ADHD participants made significantly more errors of commission than the control participants on the CPT-II , whereas the two groups made the same number of errors of commission on the SOA . The ADHD group also sought discriminative feedback significantly more actively on the SOA than the control group and performed at par with the control group in all respects . There was no speed/accuracy trade-off , nor was there any evidence of other costs of normalization on the SOA . Impulsiveness in adult ADHD is compensable on a task simulating the work environment Background Current st and ardized treatments for cognitive impairment in attention-deficit/hyperactivity disorder remain limited and their efficacy restricted . Transcranial direct current stimulation ( tDCS ) is a promising tool for enhancing cognitive performance in several neuropsychiatric disorders . Nevertheless , the effects of tDCS in reducing cognitive impairment in patients with attention-deficit/hyperactivity disorder ( ADHD ) have not yet been investigated . Methods A parallel , r and omized , double-blind , sham-controlled trial was conducted to examine the efficacy of tDCS on the modulation of inhibitory control in adults with ADHD . Thirty patients were r and omly allocated to each group and performed a go/no-go task before and after a single session of either anodal stimulation ( 1 mA ) over the left dorsolateral prefrontal cortex or sham stimulation . Results A nonparametric two- sample Wilcoxon rank-sum ( Mann-Whitney ) test revealed no significant differences between the two groups of individuals with ADHD ( tDCS vs. sham ) in regard to behavioral performance in the go/no go tasks . Furthermore , the effect sizes of group differences after treatment for the primary outcome measures —correct responses , impulsivity and omission errors — were small . No adverse events result ing from stimulation were reported . Conclusion According to these findings , there is no evidence in support of the use of anodal stimulation over the left dorsolateral prefrontal cortex as an approach for improving inhibitory control in ADHD patients . To the best of our knowledge , this is the first clinical study to assess the cognitive effects of tDCS in individuals with ADHD . Further research is needed to assess the clinical efficacy of tDCS in this population . Trial Registration Clinical Trials.gov Using a within-subject design and both high- and low-interest tasks , this study examined the effects of reward ( R ) , response cost ( RC ) , and no contingency ( NR ) on performance and motivation of 22 children with attention deficit-hyperactivity disorder ( ADHD ) and 22 controls . Dependent variables included performance measures , self-rated performance and motivation , and a new measure of behavioral motivation based on a 2-min postcontingency task .  Both contingencies benefited some aspects of the performance of ADHD children ; relative to R , RC showed stronger effects but at the expense of decreased self-rated motivation on the low-interest task . The performance of controls did not differ across tasks , whereas ADHD children performed relatively better on the high-interest task . Neither contingency decreased motivation measures relative to NR for either group . For ADHD children , motivational effects appeared to be influenced by self-perceptions of performance The objective of this study was to evaluate the efficacy of a multicomponent program for treating attention-deficit/hyperactivity disorder ( ADHD ) carried out by teachers in a classroom context . Dependent measures included neuropsychological tasks , behavioral rating scales for parents and teachers , direct observation of behavior in the classroom , and academic records of children with ADHD . Fifty children with ADHD participated in the study . The teachers of 29 of the 50 students  were trained in the use of behavior modification techniques , cognitive behavior strategies , and instructional management strategies . The other 21 students formed the  control group . Parents ' and teachers'ratings detected improvements in primary symptoms ( inattention — disorganization , hyperactivity — impulsivity ) and in behavioral difficulties usually associated with ADHD ( e.g. , antisocial behavior , psychopathological disorders , anxiety ) . Furthermore , the results showed increased academic scores , enhanced classroom behavioral observations , and improved teachers ' knowledge about the strategies directed toward responding to the children 's educational needs Attention Deficit Hyperactivity Disorder ( ADHD ) mainly affects the academic performance of children and adolescents . In addition to bringing physical and mental health benefits , physical activity has been used to prevent and improve ADHD comorbidities ; however , its effectiveness has not been quantified . In this study , the effect of physical activity on children 's attention was measured using a computer game . Intense physical activity was promoted by a relay race , which requires a 5-min run without a rest interval . The proposed physical stimulus was performed with 28 volunteers : 14 with ADHD ( GE-EF ) and 14 without ADHD symptoms ( GC-EF ) . After 5 min of rest , these volunteers accessed the computer game to accomplish the tasks in the shortest time possible . The computer game was also accessed by another 28 volunteers : 14 with ADHD ( GE ) and 14 without these symptoms ( GC ) . The response time to solve the tasks that require attention was recorded . The results of the four groups were analyzed using D'Agostino statistical tests of normality , Kruskal-Wallis analyses of variance and post-hoc Dunn tests . The groups of volunteers with ADHD who performed exercise ( GE-EF ) showed improved performance for the tasks that require attention with a difference of 30.52 % compared with the volunteers with ADHD who did not perform the exercise ( GE ) . The ( GE-EF ) group showed similar performance ( 2.5 % difference ) with the volunteers in the ( GC ) group who have no ADHD symptoms and did not exercise . This study shows that intense exercise can improve the attention of children with ADHD and may help their school performance This study examined whether adolescent females with attention-deficit/hyperactivity disorder ( ADHD ) are differentially responsive than their male counterparts to extended-release stimulant medications . This investigation may bear special importance for an adolescent ( as opposed to child ) population , because hormonal and metabolism differences between sexes are most likely to emerge at this time . Male ( n = 19 ) and female ( n = 16 ) adolescents , ages 16–19 with ADHD , participated in a r and omized , double-blind crossover study evaluating the effectiveness of osmotic-release methylpheni date , extended release amphetamine salts , placebo , and routine limited medication regimen . Medication efficacy was evaluated using ADHD symptom ratings from adolescent self-report and parent report , along with objective measures of inattention and hyperactivity/impulsivity during driving performance and neuropsychological tasks . Males and females were largely equivalent in impairment , and medication was similarly effective in reducing symptoms . No interactions were found between sex and medication on any measure of effectiveness or side effects . This finding suggests that the efficacy and tolerability of extended-release stimulant medications is equivalent for male and female adolescents with ADHD This study was conducted to determine the effect of acute aerobic exercise on executive function in children with attention deficit hyperactivity disorder ( ADHD ) . Forty children with ADHD were r and omly assigned into exercise or control groups . Participants in the exercise group performed a moderate intensity aerobic exercise for 30 min , whereas the control group watched a running/exercise-related video .  Neuropsychological tasks , the Stroop Test and the Wisconsin Card Sorting Test ( WCST ) , were assessed before and after each treatment . The results indicated that acute exercise facilitated performance in the Stroop Test , particularly in the Stroop Color-Word condition . Additionally , children in the exercise group demonstrated improvement in specific WCST performances in Non-perseverative Errors and Categories Completed , whereas no influences were found in those performances in the control group . Tentative explanations for the exercise effect postulate that exercise allocates attention re sources , influences the dorsolateral prefrontal cortex , and is implicated in exercise-induced dopamine release . These findings are promising and additional investigations to explore the efficacy of exercise on executive function in children with ADHD are encouraged Methylpheni date ( MPH ) often ameliorates attention-deficit/hyperactivity disorder ( ADHD ) behavioral dysfunction according to indirect informant reports and rating scales . The st and ard of care behavioral MPH titration approach seldom includes direct neuropsychological or academic assessment data to determine treatment efficacy . Documenting “ cool ” executive-working memory ( EWM ) and “ hot ” self-regulation ( SR ) neuropsychological impairments could aid in differential diagnosis of ADHD subtypes and determining cognitive and academic MPH response . In this study , children aged 6 to 16 with ADHD inattentive type ( IT ; n = 19 ) and combined type ( n = 33)/hyperactive-impulsive type ( n = 4 ) ( CT ) participated in double-blind placebo-controlled MPH trials with baseline and r and omized placebo , low MPH dose , and high MPH dose conditions . EWM/ SR measures and behavior ratings/classroom observations were rank ordered separately across conditions , with nonparametric r and omization tests conducted to determine individual MPH response . Participants were subsequently grouped according to their level of cool EWM and hot SR circuit dysfunction . Robust cognitive and behavioral MPH response was achieved for children with significant baseline EWM/SR impairment , yet response was poor for those with adequate EWM/ SR baseline performance . Even for strong MPH responders , the best dose for neuropsychological functioning was typically lower than the best dose for behavior . Findings offer one possible explanation for why long-term academic MPH treatment gains in ADHD have not been realized . Implication s for academic achievement and medication titration practice s for children with behaviorally diagnosed ADHD will be discussed Behavioral and neuropsychological functioning in unmedicated children with attention-deficit/hyperactivity disorder ( ADHD ) who have a history of medication treatment ( Rx ) versus those who are treatment naïve ( TN ) has , to our knowledge , not been previously studied . Ninety-four children in four groups ( ADHD/Rx , ADHD/TN , learning disabilities [ LD ] , and controls ) were evaluated , while unmedicated , on measures of achievement , neuropsychological functioning , and behavior . The ADHD/Rx group performed significantly better than the TN group on writing , Stroop interference , and measures of attention , and performed as well as the control group on executive functioning , verbal working memory , and academics . Behaviorally , the ADHD groups showed more difficulty with mood and externalizing behaviors compared with the LD and control groups , with the ADHD/TN performing the most poorly . Findings suggest that the ADHD/Rx group shows better executive and academic functioning even when unmedicated OBJECTIVE To estimate the risks for psychopathology and functional impairments in adulthood among a longitudinal sample of youth with and without attention-deficit/hyperactivity disorder ( ADHD ) diagnosed in childhood . METHOD This was a case-controlled , 16-year ( 15 - 19 years ) prospect i ve follow-up study of ADHD . 140 boys with and 120 without DSM-III-R ADHD were recruited from pediatric and psychiatric setting s. The main outcome measures were  structured diagnostic interviews and measures of psychosocial , educational , and neuropsychological functioning . Data were collected from 1988 to 2006 . RESULTS At the 16-year follow-up , subjects with ADHD continued to significantly differ from controls in lifetime rates of antisocial , mood , anxiety , and addictive disorders , but with the exception of a higher interval prevalence of anxiety disorders ( 20 % vs 8 % ; z = 2.32 , P = .02 ) and smoking dependence ( 27 % vs 11 % ; z = 2.30 , P = .02 ) , the incidence of individual disorders in the 6-year interval between the current and prior follow-up did not differ significantly from controls . At follow-up , the ADHD subjects compared with controls were significantly ( P < .05 ) more impaired in psychosocial , educational , and neuropsychological functioning , differences that could not be accounted for by other active psychopathology . CONCLUSIONS These long-term prospect i ve findings provide further evidence for the high morbidity associated with ADHD across the life cycle , stressing the importance of early recognition of this disorder for prevention and early intervention strategies . These findings also indicate that , in adulthood , ADHD confers significant risks for impairment that can not be accounted for by other psychopathology BACKGROUND AND AIMS Children with attention deficit/hyperactivity disorder ( ADHD ) often show deficits in working memory performance .  Methylpheni date ( MPH ) is an effective medication to improve these cognitive difficulties . This study aim ed to clarify which effect MPH induces on the underlying functional networks of working memory . METHODS Fourteen boys diagnosed with ADHD and 12 healthy controls were investigated using functional magnetic resonance imaging ( fMRI ) . Each patient was tested twice , once with medication and once without . The fMRI experiments consisted of three verbal N-back tasks with increasing difficulty . Functional images were acquired on a 3 Tesla head scanner . RESULTS On the behavioral level , medicated patients performed similar to healthy controls and significantly better than without medication . On the functional level , patients showed the expected frontal and parietal activations , which were more pronounced in the 2- and 3-back tasks . Healthy controls showed significantly more activation in these regions and additional activation in the cerebellum . Interestingly , patients showed an additional effect of laterality . Left-sided frontal and parietal activation in patients was significantly less pronounced than in controls . CONCLUSION Functional data indicate different activation patterns in verbal working memory tasks between healthy controls and patients with ADHD irrespective of medication condition . Intake of MPH led to a clear improvement on a behavioral level . However , this effect was not reflected by changes in functional brain organization . MPH-induced changes leading to better performance in verbal working memory tasks might be very subtle and therefore not detectable by fMRI Objective . To assess effects of OROS methylpheni date on cognitive and academic tasks in 9 to 12 year olds with attention-deficit/hyperactivity disorder ( ADHD ) . Methods . A double-blind , within-subject , crossover design was used to compare OROS methylpheni date with placebo in a laboratory classroom setting on several cognitive and academic tasks for 68 children who met r and omization criteria . Results . Performance on the following measures was significantly better when children received individually optimized OROS methylpheni date than placebo :  math fluency and accuracy measured by the Permanent Product Math Test , ADHD symptoms observed in the laboratory setting , computerized indices of attention and impulsivity as measured by the Test of Variables of Attention ( TOVA ) , and visual — spatial working memory ( Finger Windows Backwards ) . Study medication was well tolerated ; adverse events were generally consistent with previous reports . Conclusions . OROS methylpheni date improves performance on measures of attention and vigilance , behavior , and working memory in a laboratory school setting in 9 to 12 year olds with ADHD Background Children with attention deficit hyperactivity disorder ( ADHD ) are characterised by developmentally inappropriate levels of hyperactivity , impulsivity and /or inattention and are particularly impaired when performing tasks that require a high level of cognitive control . Methylpheni date ( MPH ) and motivational incentives may help improve cognitive control by enhancing the ability to monitor response accuracy and regulate performance accordingly . Methods Twenty-eight children with DSM-IV ADHD ( combined type ) aged 9–15 years and pairwise-matched typically developing children ( CTRL ) performed a go/no-go task in which the incentives attached to performance on no-go trials were manipulated . The ADHD group performed the task off and on their usual dose of MPH . CTRL children performed the task twice but were never medicated . EEG data were recorded simultaneously and two electrophysiological indices of error monitoring , the error-related negativity ( ERN ) and error positivity ( Pe ) were measured . Amplitudes of each ERP were compared between diagnostic groups ( CTRL , ADHD ) , medication days ( Off MPH , On MPH ) and motivational conditions ( baseline – low incentive , reward , response cost ) . Results Error rates were lower in the reward and response cost conditions compared with baseline across diagnostic groups and medication days . ERN and Pe amplitudes were significantly reduced in ADHD compared with CTRL , and were significantly enhanced by MPH . Incentives significantly increased ERN and Pe amplitudes in the ADHD group but had no effect in CTRL . The effects of incentives did not interact with the effects of MPH on either ERP . Effect sizes were computed and revealed larger effects of MPH than incentives on ERN and Pe amplitudes . Conclusions The findings reveal independent effects of motivational incentives and MPH on two electrophysiological markers of error monitoring in children with ADHD , suggesting that each may be important tools for enhancing or restoring cognitive control in these children 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 OBJECTIVE The aim of this study was to assess the efficacy of atomoxetine , a new and highly selective inhibitor of the norepinephrine transporter , for executive functioning in adults with attention-deficit/hyperactivity disorder ( ADHD ) . METHOD Two identical studies using a double-blind , placebo-controlled , parallel design were conducted . Patients were adults ( Study 1 , n = 280 ; Study 2 , n = 256 ) with Diagnostic and Statistical Manual of Mental Disorders , 4th edition (DSM-IV)-defined ADHD recruited by referral and advertising . They were r and omized to 10 weeks of treatment with atomoxetine or placebo .  Executive functions were measured by the Stroop task . RESULTS There was no evidence of cognitive deterioration associated with atomoxetine treatment . Atomoxetine treatment was associated with an improvement of the Stroop colorword score . CONCLUSIONS Our results provide further support for Spencer et al. 's ( 1998 ) report that atomoxetine improves inhibitory capacity , as measured by the Stroop task . The absence of cognitive deterioration from atomoxetine , along with improved performance in a subgroup of patients in this large study , supports the safety of atomoxetine in this regard and its potential for improving a significant source of impairment for adults with ADHD
Review of the evidence suggests that  task performance  may be useful in identifying individuals with ADHD at risk for academic impairment .
However , the evidence is less compelling for identifying youth at risk for impaired social functioning or poor health outcomes .
The review also found that task performance is likely useful for predicting response to treatment with methylpheni date .
Across studies , evidence indicated that interpreting task performance in an integrated manner , such as a factor score or mean score , was more consistently useful for predicting outcomes of interest than interpreting performance from a single task .
The role that neuropsychological task performance plays in the assessment of Attention-Deficit/Hyperactivity Disorder ( ADHD ) is currently ambiguous , and findings are mixed regarding whether tasks have validity for diagnosing the disorder .
Irrespective of their validity for diagnosing ADHD , neuropsychological tasks could provide valuable information to mental health professionals if they can inform recommendations for treatment targets and modalities .
Therefore , this review sought to synthesize the available evidence related to the use of neuropsychological task performance as a tool for informing treatment planning for youth with ADHD .
Review ed studies focused on examinations of associations between task performance and academic , social , and health outcomes , as well as response to treatment .