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The science of attention‐deficit/hyperactivity disorder (ADHD) is motivated by a translational goal – the discovery and exploitation of knowledge about the nature of ADHD to the benefit of those individuals whose lives it affects. Over the past fifty years, scientific research has made enormous strides in characterizing the ADHD condition and in understanding its correlates and causes. However, the translation of these scientific insights into clinical benefits has been limited. In this review, we provide a selective and focused survey of the scientific field of ADHD, providing our personal perspectives on what constitutes the scientific consensus, important new leads to be highlighted, and the key outstanding questions to be addressed going forward. We cover two broad domains – clinical characterization and, risk factors, causal processes and neuro‐biological pathways. Part one focuses on the developmental course of ADHD, co‐occurring characteristics and conditions, and the functional impact of living with ADHD – including impairment, quality of life, and stigma. In part two, we explore genetic and environmental influences and putative mediating brain processes. In the final section, we reflect on the future of the ADHD construct in the light of cross‐cutting scientific themes and recent conceptual reformulations that cast ADHD traits as part of a broader spectrum of neurodivergence. Read the Commentary on this article at doi: 10.1111/jcpp.13758. [ABSTRACT FROM AUTHOR]

Background: Social attention affords learning opportunities across development and may contribute to individual differences in developmental trajectories, such as between male and female individuals, and in neurodevelopmental conditions, such as autism. Methods: Using eye‐tracking, we measured social attention in a large cohort of autistic (n = 123) and nonautistic females (n = 107), and autistic (n = 330) and nonautistic males (n = 204), aged 6–30 years. Using mixed Growth Curve Analysis, we modelled sex and diagnostic effects on the temporal dynamics of proportional looking time to three types of social stimuli (lean‐static, naturalistic‐static, and naturalistic‐dynamic) and examined the link between individual differences and dimensional social and nonsocial autistic traits in autistic females and males. Results: In the lean‐static stimulus, average face‐looking was higher in females than in males of both autistic and nonautistic groups. Differences in the dynamic pattern of face‐looking were seen in autistic vs. nonautistic females, but not males, with face‐looking peaking later in the trial in autistic females. In the naturalistic‐dynamic stimulus, average face‐looking was higher in females than in males of both groups; changes in the dynamic pattern of face looking were seen in autistic vs. nonautistic males, but not in females, with a steeper peak in nonautistic males. Lower average face‐looking was associated with higher observer‐measured autistic characteristics in autistic females, but not in males. Conclusions: Overall, we found stronger social attention in females to a similar degree in both autistic and nonautistic groups. Nonetheless, the dynamic profiles of social attention differed in different ways in autistic females and males compared to their nonautistic peers, and autistic traits predicted trends of average face‐looking in autistic females. These findings support the role of social attention in the emergence of sex‐related differences in autistic characteristics, suggesting an avenue to phenotypic stratification. [ABSTRACT FROM AUTHOR]

Background: Meta‐analyses suggest an association between autism spectrum disorder (ASD) and obesity, but the factors underlying this association remain unclear. This study investigated the association between ASD and obesity stratified on intellectual disability (ID). In addition, in order to gain insight into possible shared etiological factors, the potential role of shared familial liability was examined. Method: We studied a cohort of 3,141,696 individuals by linking several Swedish nationwide registers. We identified 35,461 individuals with ASD and 61,784 individuals with obesity. Logistic regression models were used to estimate the association between ASD and obesity separately by ID and sex and by adjusting for parental education, psychiatric comorbidity, and psychotropic medication. Potential shared familial etiologic factors were examined by comparing the risk of obesity in full siblings, maternal and paternal half‐siblings, and full‐ and half‐cousins of individuals with ASD to the risk of obesity in relatives of individuals without ASD. Results: Individuals with ASD + ID (OR = 3.76 [95% CI, 3.38–4.19]) and ASD−ID (OR = 3.40 [95% CI, 3.23–3.58]) had an increased risk for obesity compared with individuals without ASD. The associations remained statistically significant when adjusting for parental education, psychiatric comorbidity, and medication. Sex‐stratified analyses indicated a higher relative risk for males compared with females, with statistically significant interaction effects for ASD−ID, but not for ASD+ID in the fully adjusted model. First‐degree relatives of individuals with ASD+ID and ASD−ID had an increased risk of obesity compared with first‐degree relatives of individuals without ASD. The obesity risk was similar in second‐degree relatives of individuals with ASD+ID but was lower for and ASD−ID. Full cousins of individuals with ASD+ID had a higher risk compared with half‐cousins of individuals with ASD+ID). A similar difference in the obesity risk between full cousins and half‐cousins was observed for ASD−ID. Conclusions: Individuals with ASD and their relatives are at increased risk for obesity. The risk might be somewhat higher for males than females. This warrants further studies examining potential common pleiotropic genetic factors and shared family‐wide environmental factors for ASD and obesity. Such research might aid in identifying specific risks and underlying mechanisms in common between ASD and obesity. [ABSTRACT FROM AUTHOR]

Background: Studies of infants with an elevated likelihood of autism spectrum disorder can identify basic developmental processes that are associated with subsequently emerging clinical symptoms. Atypical responsiveness to sounds in infancy is such a potential early marker of autism. Here, we used pupillometry to quantify reactivity to social and nonsocial sounds in infants with a subsequent diagnosis. Previous research suggest that pupil dilation reflects attentional alerting, and link it to the locus coeruleus norepinephrine system. Methods: We measured pupil dilation responses to child‐directed speech and the sound of running water; sounds infants often hear in their everyday life. The final sample consisted of 99 ten‐month‐old infants (52 girls), of whom 68 had an elevated likelihood of autism and 31 were typically developing low‐likelihood infants. At follow‐up (36 months of age), 18 children in the elevated‐likelihood group were diagnosed with autism. Results: Compared to infants without diagnosis, the infants who were subsequently diagnosed with autism had larger pupil dilation when listening to nonsocial sounds, while reactivity to speech was strikingly similar between groups. In the total sample, more pupil dilation to the nonsocial sound was associated with higher levels of autistic symptoms. We also found that on a trial‐by‐trial basis, across all conditions and groups, more pupil dilation was associated with making fewer gaze shifts. Conclusions: This study did not find evidence of atypical pupillary reactivity to child‐directed speech early in life in autism. Instead, the results suggest that certain nonsocial sounds elicit atypically strong alerting responses in infants with a subsequent autism diagnosis. These findings may have important theoretical and clinical implications. [ABSTRACT FROM AUTHOR]

Many youths with attention‐deficit/hyperactivity disorder (ADHD) experience significant long‐term impairment and may develop concurrent mental and somatic health difficulties as adults. This is associated with burden and costs for the individual and society which could be prevented through continued support in youth. Yet, only few young people transition to adult mental health services for ongoing care in different countries worldwide. We provide an overview on current transition practices, highlighting the gaps in knowledge and the barriers to effective service transitioning, while considering the large geographical variation in available guidelines and service provision. For ease of use, this review is organized in a question‐and‐answer format covering different aspects of the transition process and considering both service users' and clinicians' perspectives. Consensus is needed to identify those that require continued care, the optimal timing to arrange transition, and the most suitable services. Finally, we discuss cost‐effectiveness of transition practices, consider examples of best practice, and propose recommendations on how to improve transitional care, including the importance of service users' input into transition planning. [ABSTRACT FROM AUTHOR]

Background: Top‐down volitional command of eye movements may serve as a candidate endophenotype of ADHD, an important function underlying goal‐directed action in everyday life. In this twin study, we examined the relation between performance on a response inhibition eye‐tracking paradigm and parent‐rated ADHD traits in a population‐based twin sample. We hypothesized that altered eye movement control is associated with the severity of ADHD traits and that this association is attributable to genetic factors. Methods: A total of 640 twins (320 pairs, 50% monozygotic) aged 9–14 years) from the Child and Adolescent Twin Study in Sweden (CATSS) participated. Twins performed the antisaccade task indexing inhibitory alterations as either direction errors (following exogenous cues rather than instructions) or premature anticipatory eye movements (failure to wait for cues). We calculated the associations of eye movement control and ADHD traits using linear regression mixed‐effects models and genetic and environmental influences with multivariate twin models. Results: Premature anticipatory eye movements were positively associated with inattentive traits (β =.17; 95% CI: 0.04, 0.31), while controlling for hyperactive behaviors and other covariates. Both premature anticipatory eye movements and inattention were heritable (h2 = 0.40, 95% CI: 0.22, 0.56; h2 = 0.55; 95% CI: 0.42, 0.65; respectively), and their genetic correlation was small but statistically significant (r =.19, 95% CI: 0.02, 0.36). However, the genetic correlation did not remain significant after adjusting for covariates (age, sex, hyperactivity traits, IQ). No link was found between direction errors and ADHD traits. Conclusions: This study indicates that there is a specific, genetically influenced, relation between top‐down eye movement control and the inattentive traits typical of ADHD. [ABSTRACT FROM AUTHOR]

Background: Effective multisensory processing develops in infancy and is thought to be important for the perception of unified and multimodal objects and events. Previous research suggests impaired multisensory processing in autism, but its role in the early development of the disorder is yet uncertain. Here, using a prospective longitudinal design, we tested whether reduced visual attention to audiovisual synchrony is an infant marker of later‐emerging autism diagnosis. Methods: We studied 10‐month‐old siblings of children with autism using an eye tracking task previously used in studies of preschoolers. The task assessed the effect of manipulations of audiovisual synchrony on viewing patterns while the infants were observing point light displays of biological motion. We analyzed the gaze data recorded in infancy according to diagnostic status at 3 years of age (DSM‐5). Results: Ten‐month‐old infants who later received an autism diagnosis did not orient to audiovisual synchrony expressed within biological motion. In contrast, both infants at low‐risk and high‐risk siblings without autism at follow‐up had a strong preference for this type of information. No group differences were observed in terms of orienting to upright biological motion. Conclusions: This study suggests that reduced orienting to audiovisual synchrony within biological motion is an early sign of autism. The findings support the view that poor multisensory processing could be an important antecedent marker of this neurodevelopmental condition. [ABSTRACT FROM AUTHOR]

Background An individual's subjective perception of well-being is increasingly recognized as an essential complement to clinical symptomatology and functional impairment in children's mental health. Measurement of quality of life (QoL) has the potential to give due weight to the child's perspective. Scope and methodology Our aim was to critically review the current evidence on how childhood mental disorders affect QoL. First, the major challenges in this research field are outlined. Then we present a systematic review of QoL in children and adolescents aged 0-18 years formally diagnosed with a mental and behavioural disorder, as compared to healthy or typically developing children or children with other health conditions. Finally, we discuss limitations of the current evidence base and future directions based on the results of the systematic review and other relevant literature. Findings and conclusions The systematic review identified 41 eligible studies. All were published after the year 2000 and 21 originated in Europe. The majority examined QoL in neurodevelopmental disorders, including attention-deficit hyperactivity disorder ( k = 17), autism spectrum disorder ( k = 6), motor disorders ( k = 5) and intellectual disability ( k = 4). Despite substantial heterogeneity, studies demonstrate that self-reported global QoL is significantly reduced compared to typical/healthy controls across several disorders and QoL dimensions. Parents' ratings were on average substantially lower, casting doubt on the validity of proxy-report. Studies for large diagnostic groups such as depressive disorders, anxiety disorders, (early onset) schizophrenia and eating disorders are largely lacking. We conclude that representative, well-characterized normative and clinical samples as well as longitudinal and qualitative designs are needed to further clarify the construct of QoL, to derive measures of high ecological validity, and to examine how QoL fluctuates over time and is attributable to specific conditions or contextual factors. [ABSTRACT FROM AUTHOR]