Related Articles

Objectives

Attention deficit hyperactivity disorder (ADHD) in adults has been associated with disturbances of attention and executive functions. Furthermore, impairments of verbal and figural retrospective memory were reported. However, little is known about the effects of ADHD on prospective memory, the execution of delayed intentions in the future.

Methods

The present study compared the performance of 45 adult patients with ADHD not treated with stimulant medication with the performance of 45 matched healthy individuals on a paradigm of complex prospective memory which measured task planning, plan recall, self-initiation and execution. Furthermore, the contribution of other cognitive functions to prospective memory functioning was assessed, including measures of attention, executive functions and memory.

Results

A large-scale impairment could be observed in task planning abilities in patients with ADHD. Only negligible to small effects were found for plan recall, self-initiation and execution. Inhibition was identified to contribute significantly to performance on task planning.

Conclusions

The present findings suggest that four cognitive components contribute to the performance of prospective memory. Impairments of prospective memory mainly emerged from deficient planning abilities in adults with ADHD. Implications on behavioral based intervention strategies are discussed.

Background

Attention deficit hyperactivity disorder (ADHD) in adulthood is not fully treated by psychopharmacological treatment alone. The main aim of the current study was to evaluate a newly developed cognitive behaviour therapy (CBT) based group programme, the Reasoning and Rehabilitation for ADHD Youths and Adults (R&R2ADHD), using a randomized controlled trial.

Methods

54 adults with ADHD already receiving psychopharmacological treatment were randomly allocated to an experimental (CBT/MED) treatment condition (n = 27) and a 'treatment as usual' (TAU/MED) control condition (n = 27) that did not receive the CBT intervention. The outcome measures were obtained before treatment (baseline), after treatment and at three month follow-up and included ADHD symptoms and impairments rated by independent assessors, self-reported current ADHD symptoms, and comorbid problems.

Results

The findings suggested medium to large treatment effects for ADHD symptoms, which increased further at three month follow-up. Additionally, comorbid problems also improved at follow-up with large effect sizes.

Conclusions

The findings give support for the effectiveness of R&R2ADHD in reducing ADHD symptoms and comorbid problems, an improving functions associated with impairment. The implications are that the benefits of R&R2ADHD are multifaceted and that combined psychopharmacological and CBT based treatments may add to and improve pharmacological interventions.

Trial registration

ACTRN12611000533998 (http://www.ANZCTR.org.au/ACTRN12611000533998.aspx)

Objectives

To estimate the prevalence and workplace consequences of adult attention-deficit/hyperactivity disorder (ADHD).

Methods

Ann ADHD screen was administered to 18–44 year-old respondents in ten national surveys in the WHO World Mental Health (WMH) Survey Initiative (n = 7075 in paid or self employment; response rate 45.9–87.7% across countries). Blinded clinical reappraisal interviews were administered in the US to calibrate the screen. Days out of role were measured in the WHO Disability Assessment Schedule (WHO-DAS). Questions were also asked about ADHD treatment.

Results

An average of 3.5% of workers in the ten countries was estimated to meet DSM-IV criteria for adult ADHD (inter-quartile range: 1.3–4.9%). ADHD was more common among males than females and less common among professionals than other workers. ADHD was associated with a statistically significant 22.1 annual days of excess lost role performance compared to otherwise similar respondents without ADHD. No difference in the magnitude of this effect was found by occupation, education, age, gender, or partner status. This effect was most pronounced in Colombia, Italy, Lebanon, and the US. Although only a small minority of workers with ADHD ever received treatment for this condition, higher proportions were treated for comorbid mental-substance disorders.

Conclusions

ADHD is a relatively common condition among working people in the countries studied and is associated with high work impairment in these countries. This impairment, in conjunction with the low treatment rate and the availability of cost-effective therapies, suggests that ADHD would be a good candidate for targeted workplace screening and treatment programs.

Main messages

A high proportion of childhood ADHD persists into adulthood.

An average of 3.5% of workers in nationally representative surveys carried out in 10 countries met criteria for current DSM-IV adult ADHD.

Workers with ADHD have an average 8.4 excess sickness absence days per year and even higher annualized average excess numbers of workdays associated with reduced work quantity (21.7 days) and quality (13.6 days).

Only a small majority of these workers are treated for ADHD despite evidence that such treatment can be quite effective in improving functioning.

Policy implications

ADHD is a good candidate for targeted workplace screening and treatment programs.

Evaluation is needed to determine the extent to which best-practices outreach and treatment interventions would result in improvements in work performance that have a positive return-on-investment from the employer perspective.

Objective

Neurocognitive deficits associated with attention deficit-hyperactivity disorder (ADHD) may be useful intermediate endophenotypes for determining specific genetic pathways that contribute to ADHD.

Methods

This study administered 17 measures from prominent neuropsychological theories of ADHD (executive function, processing speed, arousal regulation and motivation/delay aversion) in dizygotic (DZ) twin pairs discordant for ADHD and control twin pairs (ages 8–18) in order to compare performance between twins affected with ADHD (n = 266), their unaffected co-twins (n = 228), and control children from twin pairs without ADHD or learning difficulties (n = 332).

Results

ADHD subjects show significant impairment on executive function, processing speed, and response variability measures compared to control subjects. Unaffected cotwins of ADHD subjects are significantly impaired on nearly all the same measures as their ADHD siblings, even when subclinical symptoms of ADHD are controlled.

Conclusion

Executive function, processing speed, and response variability deficits may be useful endophenotypes for genetic studies of ADHD.

Background

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder that starts in childhood and frequently persists in adults. Several theories postulate deficits in ADHD that have effects across many executive functions or in more narrowly defined aspects, such as response inhibition. Electrophysiological studies on children, however, indicate that ADHD is not associated with a core deficit of response inhibition, as abnormal inhibitory processing is typically preceded or accompanied by other processing deficits. It is not yet known if this pattern of abnormal processing is evident in adult ADHD.

Methods

The objective of this paper was to investigate event-related potential indices of preparatory states and subsequent response inhibition processing in adults with ADHD. Two cued continuous performance tasks were presented to 21 adults meeting current criteria for adult ADHD and combined type ADHD in childhood, and 20 controls.

Results

The ADHD group exhibited significantly weaker orienting attention to cues, cognitive preparation processes and inhibitory processing. In addition, we observed a strong correlation between the resources allocated to orienting to cues and the strength of the subsequent response strength control processes, suggesting that orienting deficits partly predict and determine response control deficits in ADHD.

Conclusions

These findings closely resemble those previously found in children with ADHD, which indicate that there is not a core response inhibition deficit in ADHD. These findings therefore suggest the possibility of developmental stability into adulthood of the underlying abnormal processes in ADHD.

Attention Deficit Hyperactivity Disorder (ADHD) is a disorder characterized by attentional difficulties. Mindfulness is a receptive attention to present experience. Both ADHD and mindfulness are associated with attention and personality. This study tests whether individuals with ADHD have lower mindfulness scores than controls and, if true, whether personality contributes to these differences. 105 adults (half with ADHD) were assessed for mindfulness, using the Kentucky Inventory of Mindfulness Skills, and personality, using the Tridimensional Character Inventory. Individuals with ADHD report themselves as less mindful than non-ADHD controls and more novelty-seeking, less self-directed, and more self-transcendent. Mindfulness is negatively associated with ADHD and positively associated with self-directedness and self-transcendence. Analyses of subscales of mindfulness suggest that ADHD is associated most with the ‘Acting in Awareness’ dimension perhaps due to shared items reflecting attentional variability. The current findings support that a large portion of variability in trait mindfulness can be explained by ADHD status and personality traits of self-directedness and self-transcendence. It further suggests that interventions that increase mindfulness might improve symptoms of ADHD and increase self-directedness and/or self-transcendence.

Background

This study examined neuropsychological functioning in a longitudinal sample of adolescents/young adults with ADHD and controls as a function of the persistence of ADHD. We hypothesized that measures of executive processes would parallel adolescent clinical status, with ADHD-Persisters, but not Remitters, differing significantly from Controls. In contrast, Persisters and Remitters were hypothesized to perform similarly, and different from Controls, on tasks requiring less effortful processing.

Methods

Ninety-eight participants diagnosed with ADHD in childhood were reevaluated approximately 10 years later. Eighty-five never-ADHD controls similar in age, IQ, and sex distribution served as a comparison group. Participants were administered a psychiatric interview and neuropsychological test battery.

Results

Those with childhood ADHD demonstrated broad neuropsychological deficits relative to Controls. When the group with childhood ADHD was subdivided based on adolescent ADHD status, compared to Controls, both Persisters and Remitters showed deficient perceptual sensitivity and response variability, and increased ankle movements recorded by a solid-state actigraph. Only Persisters differed from controls on several measures of more effortful executive processes.

Conclusions

Findings provide preliminary support to the hypothesis that ADHD is associated with early-appearing and enduring subcortical dysfunction, while recovery over the course of development is associated with improvements in executive control functions.

A tendency to focus on details at the expense of configural information, 'weak coherence', has been proposed as a cognitive style in autism. In the present study we tested whether weak coherence might be the result of executive dysfunction, by testing clinical groups known to show deficits on tests of executive control. Boys with autism spectrum disorders (ASD) were compared with age- and intelligence quotient (IQ)-matched boys with attention-deficit/hyperactivity disorder (ADHD), and typically developing (TD) boys, on a drawing task requiring planning for the inclusion of a new element. Weak coherence was measured through analysis of drawing style. In line with the predictions made, the ASD group was more detail-focused in their drawings than were either ADHD or TD boys. The ASD and ADHD groups both showed planning impairments, which were more severe in the former group. Poor planning did not, however, predict detail-focus, and scores on the two aspects of the task were unrelated in the clinical groups. These findings indicate that weak coherence may indeed be a cognitive style specific to autism and unrelated to cognitive deficits in frontal functions.

To examine effects of group (Attention-Deficit/Hyperactivity Disorder [ADHD] versus Typically Developing [TD]), sex, and ADHD subtype on “process/optional” measures of executive functioning, children (n = 123; 54 ADHD, 69 TD) aged 8−16 completed subtests from the D-KEFS. No group, sex, or ADHD subtype effects were found on optional measures from the Trail Making, Color–Word Interference, and Tower tests. A significant interaction was found for Verbal Fluency Total Repetition Errors; boys with Combined/Hyperactive-Impulsive (ADHD-C/HI) type ADHD performed better than ADHD-C/HI girls, whereas girls with Inattentive type ADHD (ADHD-I) performed better than ADHDI boys. Overall, children with ADHD did not differ from TD on most optional measures from the D-KEFS. When sex and ADHD subtype were considered, children with the subtype of ADHD less common for sex were at greater risk for poorer performance.

This study compared adult women with childhood ADHD to adult women without childhood ADHD and to adult men with childhood ADHD. The participants, all from a larger longitudinal study, included 30 women and 30 men (approximately age 23 to 24) with childhood ADHD, and 27 women without ADHD. Women with childhood ADHD were matched to comparison women on age, ethnicity, and parental education, and to men with childhood ADHD on age, ethnicity, and IQ. Self- and parent-reports of internalizing, interpersonal, academic, and job impairment, as well as substance use and delinquency indicated group differences on measures of self-esteem, interpersonal and vocational functioning, as well as substance use. Follow-up planned comparison tests revealed that almost all of these differences emerged by diagnostic status, and not by gender. This study adds to research on the negative adult outcomes of ADHD and demonstrates that the outcomes of men and women with childhood ADHD are relatively similar.

Background

The Attention Network Test (ANT) generates measures of different aspects of attention/executive function. In the present study we investigated whether adults with ADHD performed different from controls on measures of accuracy, variability and vigilance as well as the control network. Secondly, we studied subgroups of adults with ADHD, expecting impairment on measures of the alerting and control networks in a subgroup with additional symptoms of affective fluctuations.

Methods

A group of 114 adults (ADHD n = 58; controls n = 56) performed the ANT and completed the Adult ADHD Rating Scale (ASRS) and the Mood Disorder Questionnaire (MDQ). The latter was used to define affective fluctuations.

Results

The sex distribution was similar in the two groups, but the ADHD group was significantly older (p = .005) and their score on a test of intellectual function (WASI) significantly lower than in the control group (p = .007). The two groups were not significantly different on measures of the three attention networks, but the ADHD group was generally less accurate (p = .001) and showed a higher variability through the task (p = .033).

The significance was only retained for the accuracy measure when age and IQ scores were controlled for. Within the ADHD group, individuals reporting affective fluctuations (n = 22) were slower (p = .015) and obtained a lower score on the alerting network (p = .018) and a higher score on the conflict network (p = .023) than those without these symptoms. The significance was retained for the alerting network (p = .011), but not the conflict network (p = .061) when we controlled for the total ASRS and IQ scores.

Discussion

Adults with ADHD were characterized by impairment on accuracy and variability measures calculated from the ANT. Within the ADHD group, adults reporting affective fluctuations seemed to be more alert (i.e., less impacted by alerting cues), but slower and more distracted by conflicting stimuli than the subgroup without such fluctuations. The results suggest that the two ADHD subgroups are characterized by distinct patterns of attentional problems, and that the symptoms assessed by MDQ contribute to the cognitive heterogeneity characterizing groups of individuals with ADHD.

Objective

The primary aim of this study was to compare electronic monitoring with other measures of adherence to Osmotic-controlled Release Oral delivery System methylphenidate in children with attention-deficit hyperactivity disorder (ADHD). The secondary aim was to analyze the relationships between adherence and clinical factors, including ADHD symptoms.

Methods

Thirty-nine children diagnosed with ADHD were monitored for adherence to medication over the course of eight weeks. Medication adherence was assessed using the Medication Event Monitoring System (MEMS), which is a bottle cap with a microprocessor that records all instances and times that the bottle is opened; patient self-report; clinician rating; and pill count. Information, including demographic and clinical characteristics, symptom rating scale, and psychological test results, were also collected. The relationships between adherence and clinical factors, including ADHD rating scores of baseline and of the changes, were assessed.

Results

The rate of non-adherence measured by the MEMS was found to be 46.2%, which was considerably higher than those of the patient self-report (17.9%), clinician rating (31.7%), and pill count (12.8%) of non-adherence. The rate of adherence measured by the MEMS was not significantly associated with baseline symptom severity or symptom changes over the eight weeks, although non-adherent group showed more severe baseline symptoms and inferior improvement.

Conclusion

Adherence as measured by the MEMS showed a discrepancy with other measures of adherence in patients with ADHD. The symptom severity and level of improvement were not related to adherence with MEMS. Further studies are needed to evaluate the variables that may impact medication adherence in children with ADHD.

Introduction:

Smokers with attention deficit hyperactivity disorder (ADHD) have greater difficulty quitting than those without ADHD, but preliminary data (McClernon, Kollins, Lutz, Fitzgerald, Murray, Redman, et al., 2008) suggest equivalent severity of withdrawal symptoms following brief abstinence. The objective of this study was to characterize the differential effects of intermediate term smoking abstinence on self-reported withdrawal and ADHD symptoms in adult smokers with and without ADHD.

Methods:

Forty adult (50% female), nontreatment seeking moderate-to-heavy smokers with and without ADHD were enrolled in a 12-day quit study in which monetary incentives were provided for maintaining biologically verified abstinence. Self-reported withdrawal, mood, and ADHD symptoms were measured pre- and post-quitting.

Results:

ADHD and controls did not vary on smoking or demographic variables. Significant Group × Session interactions were observed across a broad range of withdrawal symptoms and were generally characterized by greater withdrawal severity among ADHD smokers, particularly during the first 5 days of abstinence. In addition, Group × Sex × Session interactions were observed for craving, somatic symptoms, negative affect, and habit withdrawal; these interactions were driven by greater withdrawal severity among females with ADHD. Group × Session interactions were not observed for ADHD symptom scales.

Conclusions:

The results of this study suggest that smokers with ADHD, and ADHD females in particular, experience greater withdrawal severity during early abstinence—independent of effects on ADHD symptoms. Whereas additional research is needed to pinpoint mechanisms, our findings suggest that smoking cessation interventions targeted at smokers with ADHD should address their more severe withdrawal symptoms following quitting.

Context

Prospective studies of childhood attention deficit/hyperactivity disorder (ADHD) have not extended beyond early adulthood.

Objective

To test whether children diagnosed with ADHD at mean age 8 (probands) have worse educational, occupational, economic, social, marital outcomes; higher rates of ongoing ADHD, antisocial personality disorder (ASPD), substance disorders (SD); adult onset psychiatric disorders, psychiatric hospitalizations and incarcerations, than non-ADHD comparisons, at mean age 41. To test for: positive associations between probands’ ongoing ADHD and ASPD, and SD’s; and for worse social and occupational functioning in probands without ongoing psychiatric disorders, than comparisons.

Design

Prospective, 33 year follow-up study, with blind clinical assessments.

Setting

Research clinic.

Participants

135 Caucasian males with ADHD in childhood, free of conduct disorder, and 136 male comparisons without childhood ADHD (65% and 76% of original cohort, respectively).

Main Outcome Measures

Occupational, economic, and educational attainment; marital history; occupational and social functioning; ongoing and lifetime psychiatric disorders; psychiatric hospitalizations, and incarcerations.

Results

Probands had significantly worse educational, occupational, economic, social outcomes, and more divorces than comparisons; higher rates of ongoing ADHD (22% vs 5%, p<.001), ASPD (16% vs 0%, p<.001)and SD (14% vs 5%, p<.01), but not more mood or anxiety disorders (p’s=.36 and .33). Ongoing ADHD was weakly related to ongoing SD (phi=.19, p=.04), and ASPD+SD (phi=.20, p=.04). Lifetime, probands had significantly more ASPD and SD’s, but not mood or anxiety disorders, and more psychiatric hospitalizations and incarcerations than comparisons. Relative to comparisons, psychiatric disorders with onsets at age 21 or beyond were not significantly elevated in probands. Probands without ongoing psychiatric disorders had worse social, but not occupational, functioning.

Conclusions

The multiple disadvantages predicted by childhood ADHD well into adulthood began in adolescence, without increased onsets of new disorders after age 20. Findings highlight the importance of extended monitoring and treatment of children with ADHD.

Objective

To examine patterns of executive and oculomotor control in a group of both boys and girls with attention-deficit/hyperactivity disorder (ADHD).

Method

Cross-sectional study of 120 children aged 8 to 12 years, including 60 with ADHD (24 girls) and 60 typically developing controls (29 girls). Oculomotor paradigms included visually guided saccades (VGS), antisaccades, memory-guided saccades, and a go/no-go test, with variables of interest emphasizing response preparation, response inhibition, and working memory.

Results

As a group, children with ADHD demonstrated significant deficits in oculomotor response preparation (VGS latency and variability) and response inhibition but not working memory. Girls, but not boys with ADHD, had significantly longer VGS latencies, even after controlling for differences in ADHD symptom severity. The ADHD subtypes did not differ on response preparation or inhibition measures; however, children with the Inattentive subtype were less accurate on the working memory task than those with the Combined subtype.

Conclusions

Sex differences in children with ADHD extend beyond symptom presentation to the development of oculomotor control. Saccade latency may represent a specific deficit among girls with ADHD.

Objective

Nowadays, it is well known that the attention-deficit/hyperactivity disorder (ADHD) is not confined to children and adolescents. Recent data showed that a considerable portion of the general adult population may be affected by ADHD. On the other hand, the impact of ADHD on driving performance, a major area of adult life, has gained enthusiasm. More recent studies revealed an association between adult ADHD and undesirable driving problems. This study was performed to determine the association between presence of adult ADHD and traffic injuries.

Methods

In this case-control study, in a 13 month period, 140 subjects (70 drivers/riders injured in traffic accidents, and 70 age- and sex-matched non traumatic controls) were selected to participate in the study and were placed in two groups. Subjects with psychiatric comorbidities were excluded. The Conners’ Adult ADHD Rating Scale (CAARS) self-report (screening version) was used for screening adult ADHD in both groups. Finally, the occurrence of this condition was compared between the case and control groups.

Results

Sixty- nine males and one female were recruited in each group with a mean age of 29.31±9.32 (18-61) years in the case and 29.03±9.07 (range: 18-60) years in the control groups (P > 0.05). Previous history of traffic accident was significantly higher in the case group (15.7% vs. 4.3%, P=0.024). The mean driving time in a day was also significantly higher in the case group. In the case group, the scores of CAARS (the ADHD index, ADHD symptoms total, inattentive subscale and hyperactive/impulsive subscale) were positive (higher than 70) in 4.3, 10, 7.1 and 10 percent of patients respectively. Among the controls, the corresponding proportions were 4.3, 14.3, 8.6 and 8.6 percent respectively. The two groups were comparable for the mentioned rates.

Conclusion

The results of this study revealed no significant association between ADHD and traffic injuries in Tabriz- Iran.

Objective:

To investigate the possible association between untreated Attention Deficit Hyperactivity Disorder (ADHD) symptoms, as measured the Adult ADHD Self-Report Scale, and persistent nonmedical use of prescription stimulants.

Method:

Multinomial regression modeling was used to compare ADHD symptoms among three groups of college students enrolled in a longitudinal study over four years: 1) persistent nonmedical users of prescription stimulants; 2) persistent users of marijuana who did not use prescription stimulants nonmedically; and, 3) consistent non-users of drugs.

Results:

ADHD symptoms were associated with being a persistent nonmedical user of prescription stimulants, after adjustment for race/ethnicity, sex, SES, and other illicit drug use. No associations were observed between ADHD symptoms and being a persistent marijuana user or non-user.

Conclusions:

ADHD symptoms, and in particular inattention symptoms, appear to be associated with nonmedical use of prescription stimulants. Future studies are needed to clinically validate these observations.

Objective

To evaluate the efficacy and safety of osmotic-release methylphenidate (OROS-MPH) compared to placebo for attention deficit hyperactivity disorder (ADHD) and impact on substance treatment outcomes in adolescents concurrently receiving cognitive behavioral therapy (CBT) for substance use disorders (SUD).

Method

16-week randomized controlled multi-site trial of OROS-MPH + CBT versus placebo + CBT in 303 adolescents (aged 13-18), meeting DSM-IV diagnostic criteria for ADHD and SUD. Primary outcomes: (1) ADHD- clinician-administered ADHD Rating Scale (ADHD-RS), adolescent informant; (2) Substance- adolescent reported days of use in the past 28 days. Secondary outcome measures included parent ADHD-RS and weekly urine drug screens (UDS).

Results

There were no group differences on reduction in ADHD-RS scores (OROS-MPH: −19.2, 95% confidence interval [CI], −17.1 to −21.2; placebo,−21.2, 95% CI, −19.1 to −23.2) or reduction in days of substance use (OROS-MPH: −5.7 days, 95% CI, 4.0-7.4; placebo: −5.2 days, 95% CI, 3.5-7.0). Some secondary outcomes favored OROS-MPH including lower parent ADHD-RS scores at 8 (mean difference [md]=4.4, 95% CI, 0.8-7.9) and 16 weeks (md=6.9; 95% CI, 2.9-10.9) and more negative UDS in OROS-MPH (mean=3.8) compared to placebo (mean=2.8; P=0.04).

Conclusions

OROS-MPH did not show greater efficacy than placebo for ADHD or on reduction in substance use in adolescents concurrently receiving individual CBT for co-occurring SUD. However, OROS-MPH was relatively well tolerated and was associated with modestly greater clinical improvement on some secondary ADHD and substance outcome measures.

The majority of research on neurobehavioral functioning among children with Attention-Deficit/Hyperactivity Disorder (ADHD) is based on samples comprised primarily (or exclusively) of boys. Although functional impairment is well established, available research has yet to specify a neuropsychological profile distinct to girls with ADHD. The purpose of this study was to examine performance within four components of executive function (EF) in contemporaneously recruited samples of girls and boys with ADHD. Fifty-six children with ADHD (26 girls) and 90 controls (42 girls), ages 8–13, were administered neuropsychological tests emphasizing response inhibition, response preparation, working memory, and planning/shifting. There were no significant differences in age or SES between boys or girls with ADHD or their sex-matched controls; ADHD subtype distribution did not differ by sex. Compared with controls, children with ADHD showed significant deficits on all four EF components. Girls and boys with ADHD showed similar patterns of deficit on tasks involving response preparation and working memory; however, they manifested different patterns of executive dysfunction on tasks related to response inhibition and planning. Girls with ADHD showed elevated motor overflow, while boys with ADHD showed greater impairment during conscious, effortful response inhibition. Girls, but not boys with ADHD, showed impairment in planning. There were no differences between ADHD subtypes on any EF component. These findings highlight the importance of studying boys and girls separately (as well as together) when considering manifestations of executive dysfunction in ADHD.

Person-centered personality approaches are an underutilized means of illuminating clinical heterogeneity of Attention-Deficit/Hyperactivity Disorder (ADHD). In this study, latent profile analysis was conducted with personality traits to identify homogeneous profiles within the ADHD population. Participants were 548 children ages six to 18 years (302 with ADHD). Personality traits were measured via parent report on the California Q-Sort. Latent profile analysis was conducted on the Big Five Factors. A six profile solution best fit the data. Resulting groups were characterized as “disagreeable,” “introverted,” “poor control,” “well-adjusted,” “extraverted,” and “perfectionistic.” External validation of this model using ADHD diagnosis, subtypes, and comorbid psychopathology suggested that children with ADHD could be parsed into four groups: 1) an introverted group with high rates of the ADHD-inattentive type, 2) a group characterized by poor control, with high rates of ADHD-combined type (ADHD-C) and comorbid disruptive behavior disorders, 3) an extraverted group, with ADHD-C and few associated comorbid disorders, and 4) possibly, a very rare “perfectionistic” group, exhibiting obsessive traits. A person-centered personality approach may be one promising way to capture homogeneous subgroups within the ADHD population.

Theories of Attention-Deficit/Hyperactivity Disorder (ADHD) implicate dysfunctional regulation mechanisms that have been conceptually grouped into “top-down” control and “bottom-up” affective/reactive processes. This dual-process account can be invoked in relation to temperament or personality traits and may clarify how traits relate to ADHD. Two samples were examined to illuminate developmental effects. The younger sample was 179 youngsters aged 7 to 12 years (113 boys; 107 with ADHD). The older sample was 184 adolescents (109 boys; 87 with ADHD) aged 13 to 18 years. Structural equation models included parent-rated traits, teacher-rated ADHD symptoms, and laboratory-obtained executive functions. A control or “top-down” factor included cognitive control and conscientiousness/effortful control. A second factor labeled affective or “bottom-up” included neuroticism/negative emotionality, agreeableness, and reactive control. In the younger sample, these two factors were differentially and specifically related to inattention and hyperactivity, respectively. However, in the older sample, the first factor was related to inattention and hyperactivity, whereas the second factor was related to hyperactivity. Personality traits appear to map onto ADHD symptoms in a meaningful manner consistent with a dual-process model of temperament and ADHD.

Attention Deficit Hyperactivity Disorder (ADHD) is a widely diagnosed psychiatric disorder of childhood that may continue to manifest itself during adulthood. Across adults and children, inattention appears to be the most developmentally stable symptomatology of ADHD. To determine the neural systems that may be linked to such symptoms, the association between brain activation in a group of young adults in the face of an attentional challenge (the Stroop task) and inattentive symptoms was examined with functional magnetic resonance imaging. The results implicated a broad array of brain regions that are linked to behaviors compromised in ADHD, including executive function/cognitive control (prefrontal cortex, dorsal striatum), reward and motivational circuitry (ventral striatum), and stimulus representation and timing (posterior cortex and cerebellum). Also implicating these regions as being important for the manifestation of ADHD symptoms, the variability in the size of the BOLD signal across individuals was significantly higher for the ADHD group than for the control group, and variability across the time series in individuals with ADHD was linked to symptom severity and behavioral performance. The results suggest that a diverse set of brain structures is linked to ADHD symptoms and that the variability of activation within these regions may contribute to compromised attentional control.

Visual-spatial Working Memory (WM) is the most impaired executive function in children with Attention-Deficit/Hyperactivity Disorder (ADHD). Some suggest that deficits in executive functioning are caused by motivational deficits. However, there are no studies that investigate the effects of motivation on the visual-spatial WM of children with- and without ADHD. Studies examining this in executive functions other than WM, show inconsistent results. These inconsistencies may be related to differences in the reinforcement used. The effects of different reinforcers on WM performance were investigated in 30 children with ADHD and 31 non-ADHD controls. A visual-spatial WM task was administered in four reinforcement conditions: Feedback-only, 1 euro, 10 euros, and a computer-game version of the task. In the Feedback-only condition, children with ADHD performed worse on the WM measure than controls. Although incentives significantly improved the WM performance of children with ADHD, even the strongest incentives (10 euros and Gaming) were unable to normalize their performance. Feedback-only provided sufficient reinforcement for controls to reach optimal performance, while children with ADHD required extra reinforcement. Only children with ADHD showed a decrease in performance over time. Importantly, the strongest incentives (10 euros and Gaming) normalized persistence of performance in these children, whereas 1 euro had no such effect. Both executive and motivational deficits give rise to visual-spatial WM deficits in ADHD. Problems with task-persistence in ADHD result from motivational deficits. In ADHD-reinforcement studies and clinical practice (e.g., assessment), reinforcement intensity can be a confounding factor and should be taken into account. Gaming can be a cost-effective way to maximize performance in ADHD.

Background

It is now estimated that attention deficit-hyperactivity disorder (ADHD) afflicts at least 4% of adults in the United States and is associated with high levels of morbidity and functional impairment. One key area of dysfunction associated with ADHD is impaired motor vehicle operation. Our goal was to examine the association between ADHD and specific driving outcomes in a sample of adults using a driving simulator.

Methods

Subjects were 20 adults with full DSM-IV ADHD and 21 controls without ADHD of equal gender distribution. However, the mean age of subjects with ADHD was somewhat older. All analyses were adjusted for age and gender. All subjects participated in a driving simulation that lasted for one hour and consisted of a short training period, a high stimulus segment and a low stimulus segment with two distinct monotonous periods.

Results

In the second monotonous period within the low stimulus environment, ADHD subjects were significantly more likely than controls to collide with an obstacle suddenly appearing from the periphery, adjusting for age and gender.

Conclusion

Adults with ADHD were more likely than controls to collide with an obstacle during a driving simulation suggesting that deficits in directed attention may underlie driving impairments in this population.

Background

An association has been observed between the catechol-O-methyltransferase (COMT) gene, the predominant means of catecholamine catabolism within the prefrontal cortex (PFC), and neuropsychological task performance in healthy and schizophrenic adults. Since several of the cognitive functions typically deficient in children with Attention Deficit Hyperactivity Disorder (ADHD) are mediated by prefrontal dopamine (DA) mechanisms, we investigated the relationship between a functional polymorphism of the COMT gene and neuropsychological task performance in these children.

Methods

The Val108/158 Met polymorphism of the COMT gene was genotyped in 118 children with ADHD (DSM-IV). The Wisconsin Card Sorting Test (WCST), Tower of London (TOL), and Self-Ordered Pointing Task (SOPT) were employed to evaluate executive functions. Neuropsychological task performance was compared across genotype groups using analysis of variance.

Results

ADHD children with the Val/Val, Val/Met and Met/Met genotypes were similar with regard to demographic and clinical characteristics. No genotype effects were observed for WCST standardized perseverative error scores [F2,97 = 0.67; p > 0.05], TOL standardized scores [F2,99 = 0.97; p > 0.05], and SOPT error scores [F2,108 = 0.62; p > 0.05].

Conclusions

Contrary to the observed association between WCST performance and the Val108/158 Met polymorphism of the COMT gene in both healthy and schizophrenic adults, this polymorphism does not appear to modulate executive functions in children with ADHD.