The role of executive functions in mediating the relationship between adult ADHD symptoms and hyperfocus in university students.

BACKGROUND: Hyperfocus, a state of intense, narrow and prolonged attentional focus, has been associated with symptoms of attention-deficit/hyperactivity disorder (ADHD) in both clinical and non-clinical populations. Hyperfocus may be explained by difficulties in executive control, typically observed in ADHD. AIMS: To investigate (1) whether ADHD and executive functions (EF) are associated with hyperfocus and (2) whether EF mediate the relationship between ADHD symptoms and hyperfocus. METHODS AND PROCEDURES: A non-clinical sample of 380 university students (264 females) completed self-reports of ADHD, EF, hyperfocus and hyperfocus during rewarding activities. OUTCOMES AND RESULTS: Increased difficulties in EF and severity of ADHD symptoms were significantly and positively correlated with a higher frequency of hyperfocus. Moreover, EF difficulties partially mediated the relationship between ADHD and hyperfocus (after controlling for sex and substance use), but not the relationship between ADHD and hyperfocus during rewarding activities. CONCLUSIONS AND IMPLICATIONS: Difficulties in EF partially explained the higher frequency of hyperfocus, but not of hyperfocus during rewarding activities, among university students reporting more severe ADHD symptoms. Future research should investigate whether and how specific EF and other ADHD-related neurocognitive difficulties (e.g., reward sensitivity) contribute to various types of hyperfocus experiences in ADHD. WHAT THIS PAPER ADDS?: This paper is a first attempt to explain the relationship between adult ADHD symptoms and hyperfocus experiences. Our findings suggest that, although highly correlated, existing self-reports of hyperfocus measure different aspects of this experience: hyperfocus and reward-related hyperfocus. We replicate previous findings that indicated a greater frequency of both types of hyperfocus in ADHD. Additionally, we demonstrate a connection between EF difficulties and different aspects of hyperfocus. Finally, we extend previous findings by proposing that EF difficulties partially explain the relationship between ADHD and hyperfocus, but not the relationship between ADHD and reward-related hyperfocus. We hypothesize that other neurocognitive difficulties (e.g., reward sensitivity) may contribute to explain the relationship between ADHD and different aspects of hyperfocus.

Measuring the Autistic Women's Experience (AWE).

We developed a Dutch questionnaire called the Autistic Women's Experience (AWE) and compared its psychometric properties to the Autism Spectrum Quotient (AQ). Whilst attenuated gender differences on the AQ have been widely replicated, this instrument may not fully capture the unique experience of autistic women. The AWE was co-developed with autistic women to include items that reflect autistic women's experience. We investigated the AWE (49 items) and compared it with the AQ (50 items) in Dutch autistic individuals (N = 153, n = 85 women) and in the general population (N = 489, n = 246 women) aged 16+. Both the AQ and AWE had excellent internal consistency and were highly and equally predictive of autism in both women and men. Whilst there was a gender difference on the AQ among non-autistic people (men > women), there was no gender difference among autistic people, confirming all earlier studies. No gender differences were detected on the AWE overall scale, yet subtle gender differences were observed on the subscales. We conclude that the AQ is valid for both genders, but the AWE provides an additional useful perspective on the characteristics of autistic women. The AWE needs further validation in independent samples using techniques that allow for testing gender biases, as well as a confirmatory factor analysis in a larger sample.

Perspectives on Autism Spectrum Disorder Diagnosis, Symptoms, Treatment and Gender Roles: A Qualitative Study of Similarities and Differences between Sexes.

This study aims to compare the experiences of women and men of different age groups with regard to their first autism spectrum disorder (ASD) diagnosis, symptoms, treatment, and gender roles to inform our understanding in clinical practice of differences as well as similarities. Semi-structured interviews were conducted amongst 22 women (n = 12) and men (n = 10) in three adult age groups regarding their diagnostic process, symptoms, treatment, and gender roles. Participants also filled out questionnaires on gender traits, social support, coping, and quality of life. Framework analysis guidelines were followed to identify subthemes within the three pre-defined key themes of the semi-structured interviews, and quantitative analyses were performed on the questionnaire results. Women often had caregiver roles and were more focused on social and family-oriented life aspects than men. Family and societal expectations may have been different for women from an early age onward and were considered burdensome by some, but not all. Views on ASD diagnosis, symptoms, and treatment were largely individually determined. The questionnaire results mostly showed no significant sex differences. Perceived gender roles differed between participants. In diagnosis and treatment, awareness of general gender differences and gender roles is important, but inter-individual differences and similar experiences in men should not be overlooked.

Everyday Life Attention Scale (ELAS): Normative data of n = 1,874 Dutch participants.

The Everyday Life Attention Scale (ELAS) is a sensitive and reliable self-report questionnaire assessing attentional capacities of respondents in nine different situations of daily life. The ELAS has the potential to add relevant information to the clinical evaluation of attention deficits, to guide treatment planning, as well as to evaluate treatment outcome. The present study provides normative data of 1,874 Dutch speaking participants, ranging from 18 to 76 years of age, with mixed levels of education and a roughly equal distribution in gender. Normative data are calculated based on multiple linear regression models for each of the nine ELAS situations. In this article, the ELAS questionnaire as well as norm data are offered free of use. Use of normative ELAS data as presented in this study enables its use in clinical practice and research. Potential applications of the ELAS and future directions are discussed.

Testing the relation between ADHD and hyperfocus experiences.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) has been associated with hyperfocus, a transient experience of enhanced attentional focus and diminished awareness of time and the environment. AIMS: This study aims to investigate the association between the frequency, duration and pervasiveness of hyperfocus across different situations in adults with and without ADHD. METHOD AND PROCEDURES: Within a healthy sample (n = 1124), we analysed correlations between scores on the ADHD Rating Scale and self-reports of frequency, duration and pervasiveness of hyperfocus. An ADHD patient group (n = 78) was compared to matched healthy participants on all hyperfocus variables. OUTCOMES AND RESULTS: In healthy adults, the frequency of hyperfocus was positively correlated with ADHD traits; older age and higher education were correlated with fewer hyperfocus occurrences in a smaller number of situations. ADHD patients and matched controls did not differ in the occurrence, frequency, duration and pervasiveness of hyperfocus, but hyperfocus was less likely to occur in educational and social situations in ADHD patients. CONCLUSIONS AND IMPLICATIONS: Hyperfocus experiences are not specific of ADHD patients. The divergent findings might reflect multiple hyperfocus dimensions (situational and motivational) assessed in different studies which need to be addressed in future research.

The female side of pharmacotherapy for ADHD-A systematic literature review.

OBJECTIVE: This comprehensive review examined sex differences in prescription rates and efficacy or effectiveness of pharmacotherapy treatment in girls and women with attention deficit hyperactivity disorder (ADHD), while identifying gaps in the scientific knowledge on this topic. METHOD: A rigorous electronic database search was carried out in order to identify all published studies on female-specific effects of stimulants and non-stimulants in the treatment of ADHD. In total, 2672 studies were screened of which 21 studies (seven on prescription rates, 14 on effects of pharmacotherapy) met the inclusion criteria and were included for analysis. RESULTS: In all seven studies on ADHD prescription rates, girls received significantly less prescriptions than boys, a difference however no longer seen in adults with the exception of one study. Each of the 14 studies on effectiveness / efficacy found at least one sex-difference in the effects of ADHD pharmacotherapy. CONCLUSION: Several sex-differences are demonstrated in the prescription, usage and efficacy /effectiveness of both stimulant and non-stimulant ADHD pharmacotherapy. A single daily use of MPH may possibly not be optimal for girls with ADHD and ATX may be a promising medication for girls and women with ADHD. The robustness of this result requires further investigation.

Exploring neuropsychological effects of a self-monitoring intervention for ADHD-symptoms in school.

Children who have symptoms of Attention Deficit/Hyperactivity Disorder (ADHD) often experience disruptive and off-task behavior and lower school performance than would be expected based on their cognitive abilities. These behavior and achievement difficulties are a challenge to teachers, who often provide inclusive education for children with ADHD. This study explored whether a self-monitoring intervention can help children with ADHD-symptoms to reduce off-task behavior as well as improve their cognition. The participating children were seven boys in special needs education with an age between nine and twelve. The students used an interval timer to remind themselves to monitor whether they were still on task. During math classes, observations, teacher ratings and neuropsychological tests were assessed. The results showed that off-task behavior was significantly reduced during the period the interval timer was used compared to baseline (reduction from 46.8 to 27.3%), as measured by observations (effect size: η2p = .83) and this was confirmed by teacher ratings (effect size: η2p = .69). With respect to cognition, children only showed significant improvements in inhibition (effect sizes: Cohen's d = 2.62 and 1.24). The teachers as well as students evaluated the intervention mainly as positive. In line with previous studies, we found that that a self-monitoring intervention can be beneficial for children with ADHD-symptoms. Larger studies including a control group and blind observers are necessary to establish these results and to investigate the underlying mechanisms.

A situation-specific approach to measure attention in adults with ADHD: The everyday life attention scale (ELAS).

This study describes the development and utility of a new self-report measure of attentional capacities of adults with Attention Deficit Hyperactivity Disorder (ADHD): the Everyday Life Attention Scale (ELAS). Different from previous attention scales, attentional capacities are rated for nine everyday situations. Study 1 investigated the factor structure, validity, and reliability of the ELAS in 1206 healthy participants. Confirmatory factor analysis supported a situation-specific approach which categorizes everyday attention into nine situation scales: Reading, Movie, Activity, Lecture, Conversation, Assignment, Cooking, Cleaning up, and Driving. Each scale was composed of ratings for sustained, focused, selective, and divided attention as well as motivation, and had good internal consistency. Most scales showed weak correlations with ADHD Symptoms, Executive Functioning, and Memory Efficacy. Study 2 further investigated the sensitivity of the ELAS in 80 adults with ADHD compared to matched healthy controls and a mixed clinical group of 56 patients diagnosed with other psychiatric disorders. Compared to healthy controls, patients with ADHD reported reduced attentional capacities with large effect sizes on all situation scales and had a substantially higher number of situations with impaired attention scores. The ELAS may become useful in the clinical evaluation of ADHD and related psychiatric disorders in adults.

Sweat it out? The effects of physical exercise on cognition and behavior in children and adults with ADHD: a systematic literature review.

As attention-deficit/hyperactivity disorder (ADHD) is one of the most frequently diagnosed developmental disorders in childhood, effective yet safe treatment options are highly important. Recent research introduced physical exercise as a potential treatment option, particularly for children with ADHD. The aim of this review was to systematically analyze potential acute and chronic effects of cardio and non-cardio exercise on a broad range of functions in children with ADHD and to explore this in adults as well. Literature on physical exercise in patients with ADHD was systematically reviewed based on categorizations for exercise type (cardio versus non-cardio), effect type (acute versus chronic), and outcome measure (cognitive, behavioral/socio-emotional, and physical/(neuro)physiological). Furthermore, the methodological quality of the reviewed papers was addressed. Cardio exercise seems acutely beneficial regarding various executive functions (e.g., impulsivity), response time and several physical measures. Beneficial chronic effects of cardio exercise were found on various functions as well, including executive functions, attention and behavior. The acute and chronic effects of non-cardio exercise remain more questionable but seem predominantly positive too. Research provides evidence that physical exercise represents a promising alternative or additional treatment option for patients with ADHD. Acute and chronic beneficial effects of especially cardio exercise were reported with regard to several cognitive, behavioral, and socio-emotional functions. Although physical exercise may therefore represent an effective treatment option that could be combined with other treatment approaches of ADHD, more well-controlled studies on this topic, in both children and adults, are needed.

Problematic Peer Functioning in Girls with ADHD: A Systematic Literature Review.

OBJECTIVE: Children with attention deficit hyperactivity disorder (ADHD) experience many peer interaction problems and are at risk of peer rejection and victimisation. Although many studies have investigated problematic peer functioning in children with ADHD, this research has predominantly focused on boys and studies investigating girls are scant. Those studies that did examine girls, often used a male comparison sample, disregarding the inherent gender differences between girls and boys. Previous studies have highlighted this limitation and recommended the need for comparisons between ADHD females and typical females, in order to elucidate the picture of female ADHD with regards to problematic peer functioning. The aim of this literature review was to gain insight into peer functioning difficulties in school-aged girls with ADHD. METHODS: PsychINFO, PubMed, and Web of Knowledge were searched for relevant literature comparing school-aged girls with ADHD to typically developing girls (TDs) in relation to peer functioning. The peer relationship domains were grouped into 'friendship', 'peer status', 'social skills/competence', and 'peer victimisation and bullying'. In total, thirteen studies were included in the review. RESULTS: All of the thirteen studies included reported that girls with ADHD, compared to TD girls, demonstrated increased difficulties in the domains of friendship, peer interaction, social skills and functioning, peer victimization and externalising behaviour. Studies consistently showed small to medium effects for lower rates of friendship participation and stability in girls with ADHD relative to TD girls. Higher levels of peer rejection with small to large effect sizes were reported in all studies, which were predicted by girls' conduct problems. Peer rejection in turn predicted poor social adjustment and a host of problem behaviours. Very high levels of peer victimisation were present in girls with ADHD with large effect sizes. Further, very high levels of social impairment and social skills deficits, with large effect sizes, were found across all studies. Levels of pro-social behaviour varied across studies, but were mostly lower in girls with ADHD, with small to large effect sizes. Overall, social disability was significantly higher among girls with ADHD than among TD girls. CONCLUSION: Congruous evidence was found for peer functioning difficulties in the peer relationship domains of friendship, peer status, social skills/competence, and peer victimisation and bullying in girls with ADHD.

Executive Functions in Older Adults With Autism Spectrum Disorder: Objective Performance and Subjective Complaints.

Although deficits in Executive Functioning (EF) are reported frequently in young individuals with Autism Spectrum Disorders (ASD), they remain relatively unexplored later in life (>50 years). We studied objective performance on EF measures (Tower of London, Zoo map, phonetic/semantic fluency) as well as subjective complaints (self- and proxy reported BRIEF) in 36 ASD and 36 typically developed individuals (n = 72). High functioning older adults with ASD reported EF-impairments in metacognition, but did not deviate in EF task performance, except for a longer execution time of the Tower of London. The need for additional time to complete daily tasks may contribute to impairments in daily life and may be correlated to a higher level of experienced EF-difficulties in ASD.

Do blood plasma levels of oxytocin moderate the effect of nasally administered oxytocin on social orienting in high-functioning male adults with autism spectrum disorder?

OBJECTIVE: The study investigated whether baseline plasma oxytocin (OXT) concentrations might moderate the effects of nasally administered OXT on social orienting. METHODS: Thirty-one males with Autism spectrum disorder (ASD) and thirty healthy males participated in a double-blind placebo-controlled crossover trial. After administration of the compound, participants were viewing pictures from the International Affective Picture System that represented a systematic variation of pleasant, unpleasant and neutral scenes with and without humans. The outcome measures were a cardiac evoked response (ECR) and a cortical evoked long latency parietal positivity (LPP). RESULTS: Males with ASD had significantly higher plasma baseline levels than the controls. In the absence of general treatment effects, higher baseline concentrations were found to be associated with larger treatment effects, particularly in the group of males with ASD. Higher post-treatment plasma OXT concentrations were found to be associated with smaller treatment effects and larger orienting responses in the placebo situation in the group of controls. CONCLUSIONS: We interpret our findings as suggesting that it is the central availability of OXT determining how much of the nasally administered OXT will become centrally absorbed and how much of it will become released into the bloodstream.

Self-Reported Empathy in Adult Women with Autism Spectrum Disorders - A Systematic Mini Review.

INTRODUCTION: There is limited research on Autism Spectrum Disorders (ASD) in females. Although the empathy construct has been examined thoroughly in autism, little attention has been paid to empathy in adult women with this condition or to gender differences within the disorder. OBJECTIVE: Self-reported empathy in adult women with ASD was examined and compared to that of typically developed men and women as well as to men with this condition. METHODS: Online databases were searched for articles investigating self-reported empathy among adult women with ASD. Only six studies comparing women to men were identified. RESULTS: All studies found women with an ASD to report lower levels of empathy than typically developed women, and typically developed men, but similar levels to men with this condition. CONCLUSION: The self-reported empathic ability of women diagnosed with ASD resembles that of their male counterparts most closely; they show a hypermasculinisation in empathy. This is particularly surprising considering the large gender difference in empathy in the general population. DISCUSSION: One of the limitations of this review is that the current diagnostic criteria for ASD are oriented towards male-specific behaviour and fail to integrate gender specific characteristics. Hence, women diagnosed with ASD are likely to be at the male end of the continuum. The suggested hypermasculinisation of women on the spectrum, as evident from this review, may therefore be exaggerated due to a selection bias.

Performance monitoring in autism spectrum disorders: A systematic literature review of event-related potential studies.

Autism spectrum disorder (ASD) is marked by impairments in social-emotional situations, executive functioning, and behavioral regulation. These symptoms may be related to deficits in performance monitoring, i.e., the ability to observe and evaluate one's own behavior and performance which is necessary for the regulation of future behavior. The present literature review investigated electroencephalic correlates of performance monitoring in ASD. Event-related potentials (ERPs) considered in this review included internal performance monitoring components (error-related negativity, error positivity), external performance monitoring components (feedback-related negativity, feedback-P3), and observational performance monitoring components (observer error-related negativity, observer feedback-related negativity). The majority of studies point to reduced internal performance monitoring in ASD. External performance monitoring in reward-processing paradigms, where rewards are independent of performance, seems to be intact in ASD. So far, no studies have investigated the observer error-related negativity in ASD. Available data on the observer feedback-related negativity are inconclusive, since only two studies with differential study results investigated this construct in ASD. In general, results suggest that individuals with ASD have problems with internal performance monitoring and with learning from external, abstract feedback. In contrast, the processing of external, concrete feedback seems to be largely intact in ASD.

The Effects of Classroom Interventions on Off-Task and Disruptive Classroom Behavior in Children with Symptoms of Attention-Deficit/Hyperactivity Disorder: A Meta-Analytic Review.

Children with attention-deficit/hyperactivity disorder (ADHD) often exhibit problem behavior in class, which teachers often struggle to manage due to a lack of knowledge and skills to use classroom management strategies. The aim of this meta-analytic review was to determine the effectiveness of several types of classroom interventions (antecedent-based, consequence-based, self-regulation, combined) that can be applied by teachers in order to decrease off-task and disruptive classroom behavior in children with symptoms of ADHD. A second aim was to identify potential moderators (classroom setting, type of measure, students' age, gender, intelligence, and medication use). Finally, it was qualitatively explored whether the identified classroom interventions also directly or indirectly affected behavioral and academic outcomes of classmates. Separate meta-analyses were performed on standardized mean differences (SMDs) for 24 within-subjects design (WSD) and 76 single-subject design (SSD) studies. Results showed that classroom interventions reduce off-task and disruptive classroom behavior in children with symptoms of ADHD (WSDs: MSMD = 0.92; SSDs: MSMD = 3.08), with largest effects for consequence-based (WSDs: MSMD = 1.82) and self-regulation interventions (SSDs: MSMD = 3.61). Larger effects were obtained in general education classrooms than in other classroom settings. No reliable conclusions could be formulated about moderating effects of type of measure and students' age, gender, intelligence, and medication use, mainly because of power problems. Finally, classroom interventions appeared to also benefit classmates' behavioral and academic outcomes.

Acute Effects of Whole Body Vibration on Inhibition in Healthy Children.

OBJECTIVES: Whole Body Vibration (WBV) is a passive exercise method known to have beneficial effects on various physical measures. Studies on adults furthermore demonstrated beneficial effects of WBV treatment on cognition (e.g. inhibition). The present study replicated these findings in healthy children and examined acute effects of WBV treatment on inhibition. METHODS: Fifty-five healthy children (aged 8-13) participated in this within-subject design study. WBV treatment was applied by having the children sit on a chair mounted to a vibrating platform. After each condition (vibration vs. non-vibration), inhibition was measured by using the Stroop Color-Word Interference Test. Repeated measures analyses were applied in order to explore the effects of WBV treatment on inhibition, and correlations were computed between the treatment effect and participant characteristics in order to explore individual differences in treatment sensitivity. RESULTS: Three-minute WBV treatments had significant beneficial effects on inhibition in this sample of healthy children. Especially the repeated application (three times) of WBV treatment appeared beneficial for cognition. Stronger WBV treatment effects were correlated with higher intelligence and younger age, but not with symptoms of Attention Deficit Hyperactivity Disorder (ADHD). CONCLUSIONS: This study demonstrates that especially repeated WBV treatment improves inhibition in healthy children. As this cognitive function is often impaired in children with developmental disorders (e.g. ADHD), future studies should further explore the effects, working mechanism and potential applicability of WBV treatment for this target group.

Detection of feigned attention deficit hyperactivity disorder.

In recent years, there is an increasing awareness that individuals may purposely feign or exaggerate symptoms of attention deficit hyperactivity disorder (ADHD) to gain external incentives, including access to stimulant drugs or special academic accommodations. There are vast consequences of undetected feigned ADHD such as substantial costs covered by society for unnecessary assessments and treatments, unjustified occupation of limited medical resources and undermining society's trust in the existence of the disorder or the effectiveness of treatment. In times of economic crisis and cost savings in the medical sector, the detection of feigned ADHD is of importance. This review briefly describes the research on this topic with an emphasis on the approaches available for detection of feigned ADHD (i.e., self-report questionnaires, personality inventories, cognitive tests used in routine neuropsychological assessment and tests specifically designed for detecting feigned cognitive dysfunction). Promising approaches and measures are available for identifying feigned ADHD but there is an immediate need for further research.

Sex differences in orienting to pictures with and without humans: evidence from the cardiac evoked response (ECR) and the cortical long latency parietal positivity (LPP).

OBJECTIVE: This study investigated the effect of social relevance in affective pictures on two orienting responses, i.e. the evoked cardiac response (ECR), and a long latency cortical evoked potential (LPP) and whether this effect would differ between males and females. Assuming that orienting to affective social information is fundamental to experiencing affective empathy, associations between self-report measures of empathy and the two orienting responses were investigated. METHOD: ECRs were obtained from 34 female and 30 male students, and LPPs from 25 female and 27 male students viewing 414 pictures from the International Affective Picture System. Pictures portrayed pleasant, unpleasant and neutral scenes with and without humans. RESULTS: Both the ECR and LPP showed the largest response to pictures with humans in unpleasant situations. For both measures, the responses to pictures with humans correlated with self-report measures of empathy. While we found a greater male than female responsiveness to the pictures without humans in the ECR, a greater female than male responsiveness was observed in the LPP response to pictures with humans. CONCLUSION AND SIGNIFICANCE: The sensitivity of these orienting responses to social relevance and their differential contribution to the prediction of individual differences underline the validity of their combined use in clinical studies investigating individuals with social disabilities.

Sluggish cognitive tempo and its neurocognitive, social and emotive correlates: a systematic review of the current literature.

OBJECTIVES: Since the elimination of items associated with Sluggish Cognitive Tempo (SCT) during the transition from DSM-III to DSM-IV from the diagnostic criteria of Attention-deficit Hyperactivity Disorder (ADHD), interest in SCT and its associated cognitive as well as emotional and social consequences is on the increase. The current review discusses recent findings on SCT in clinical as well as community based ADHD populations. The focus is further on clinical correlates of SCT in populations different from ADHD, SCT's genetic background, SCT's association with internalizing and other behavioral comorbidities, as well as SCT's association with social functioning and its treatment efficacy. METHOD: A systematic review of empirical studies on SCT in ADHD and other pathologies in PsycInfo, SocIndex, Web of Science and PubMed using the key terms "Sluggish Cognitive Tempo", "Cognitive Tempo", "Sluggish Tempo" was performed. Thirty-two out of 63 studies met inclusion criteria and are discussed in the current review. RESULTS/CONCLUSION: From the current literature, it can be concluded that SCT is a psychometrically valid construct with additive value in the clinical field of ADHD, oppositional defiant disorder (ODD), internalizing disorders and neuro-rehabilitation. The taxonomy of SCT has been shown to be far from consistent across studies; however, the impact of SCT on individuals' functioning (e.g., academic achievement, social interactions) seems remarkable. SCT has been shown to share some of the genes with ADHD, however, related most strongly to non-shared environmental factors. Future research should focus on the identification of adequate SCT measurement to promote symptom tailored treatment and increase studies on SCT in populations different from ADHD.

Risky behavior in gambling tasks in individuals with ADHD--a systematic literature review.

OBJECTIVE: The aim of this review was to gain insight into the relationship between Attention deficit hyperactivity disorder (ADHD) and risky performance in gambling tasks and to identify any potential alternate explanatory factors. METHODS: PsycINFO, PubMed, and Web of Knowledge were searched for relevant literature comparing individuals with ADHD to normal controls (NCs) in relation to their risky performance on a gambling task. In total, fourteen studies in children/adolescents and eleven studies in adults were included in the review. RESULTS: Half of the studies looking at children/adolescents with ADHD found evidence that they run more risks on gambling tasks when compared to NCs. Only a minority of the studies on adults with ADHD reported aberrant risky behavior. The effect sizes ranged from small to large for both age groups and the outcome pattern did not differ between studies that applied an implicit or explicit gambling task. Two studies demonstrated that comorbid oppositional defiant disorder (ODD) and conduct disorder (CD) increased risky behavior in ADHD. Limited and/or inconsistent evidence was found that comorbid internalizing disorders (IDs), ADHD subtype, methylphenidate use, and different forms of reward influenced the outcomes. CONCLUSION: The evidence for increased risky performance of individuals with ADHD on gambling tasks is mixed, but is stronger for children/adolescents with ADHD than for adults with ADHD, which may point to developmental changes in reward and/or penalty sensitivity or a publication bias for positive findings in children/adolescents. The literature suggests that comorbid ODD/CD is a risk factor in ADHD for increased risky behavior. Comorbid IDs, ADHD subtype, methylphenidate use, and the form of reward received may affect risky performance in gambling tasks; however, these factors need further examination. Finally, the implications of the findings for ADHD models and the ecological validity of gambling tasks are discussed.