Annual research review: categories versus dimensions in the classification and conceptualisation of child and adolescent mental disorders--implications of recent empirical study

A semi-structured interview for the dimensional assessment of internalizing and externalizing symptoms in children and adolescents: Interview Version of the Symptoms and Functioning Severity Scale (SFSS-I)

BACKGROUND

This study evaluates the psychometric properties of the newly developed semi-structured interview, Interview Version of the Symptoms and Functioning Severity Scale (SFSS-I), which is designed to provide a dimensional assessment of internalizing and externalizing symptoms.

METHODS

Multi-informant baseline data from the OPTIE study was used, involving 358 children and adolescents aged 6 to 17 years (M = 11.54, SD = 3.4, n = 140 [39.1%] were female). Participants were screened for internalizing and externalizing symptoms. For validity analyses, caregiver (Child Behavior Checklist), youth (Youth Self Report), and teacher ratings (Teacher Report Form) were used. We performed Receiver Operating Characteristic (ROC) analyses to evaluate the effectiveness of the SFSS-I subscales in distinguishing between children and adolescents diagnosed with internalizing and externalizing disorders, as determined by clinical judgement in routine care.

RESULTS

Confirmatory factor analyses supported a correlated two-factor model for internalizing and externalizing symptoms. Acceptable to good internal consistencies (α = 0.76 to 0.89; ω = 0.76 to 0.90) and excellent interrater reliability on the scale level (ICC ≥ 0.91) was found. The ROC analyses showed an acceptable accuracy in identifying internalizing diagnoses (AUC = 0.76) and excellent accuracy for externalizing diagnoses (AUC = 0.84).

CONCLUSION

The SFSS-I demonstrates potential as a clinically-rated instrument for screening and routine outcome monitoring, offering utility in both clinical practice and research settings for the dimensional assessment of broad psychopathological dimensions.

TRIAL REGISTRATION

German Clinical Trials Register (DRKS) DRKS00016737 ( https://www.drks.de/DRKS00016737 ). Registered 17 September, 2019.

Psychometric properties of the self-report version of the Strengths and Weaknesses of ADHD Symptoms and Normal Behavior Scale in a sample of Hungarian adolescents and young adults

The Strengths and Weaknesses of ADHD Symptoms and Normal Behaviour Scale (SWAN) measures the full spectrum of attention and activity symptoms, not just the negative end of the distribution. Previous studies revealed strong psychometric properties of the parent and teacher report versions; however, there is little research on the new self-report form of the SWAN. Therefore, our research aimed to explore the psychometric characteristics of the SWAN self-report. A non-clinical sample of young women (N = 664, mean age: 20.01 years, SD: 3.08 years) completed the SWAN self-report, the Strengths and Difficulties Questionnaire (SDQ) and the Mental Health Continuum Short Form (MHC-SF). We tested several models using confirmatory factor analyses to assess the factorial validity of the SWAN self-report. Distributional characteristics, convergent, and predictive validity were assessed. A bifactor model with a general factor and a specific inattention factor (bifactor-1) provided the best fit in our data (CFI = 0.977, TLI/NFI = 0.972, RMSEA = 0.053 [90% CI: 0.047 - 0.059], SRMR = 0.061, ω = 0.90). The reliability of the general ADHD factor was good (ωh = 0.87), and the specific inattention factor was acceptable (ωh = 0.73). The distribution of the SWAN self-report scores did not differ from the normal distribution. A strong correlation between the SWAN and the SDQ Hyperactivity subscale was found. The analyses revealed good predictive validity. Our results suggest that the SWAN self-report is a valuable tool for assessing symptoms of ADHD in adolescents and young adults.

Attention-deficit/hyperactivity disorder (ADHD) in cultural context II: a comparison of the links between ADHD symptoms and waiting-related responses in Hong Kong and UK

The concept of attention-deficit/hyperactivity disorder (ADHD) is considered to have cross-cultural validity, but direct comparisons of its psychological characteristics across cultures are limited. This study investigates whether preschool children's ADHD symptoms expressed in two cultures with different views about child behaviour and parenting, Hong Kong and the UK, show the same pattern of associations with their waiting-related abilities and reactions, an important marker of early self-regulation. A community sample of 112 preschoolers (mean age = 46.22 months; 55 from UK, 57 from HK) completed three tasks measuring different waiting elements - waiting for rewards, choosing the amount of time to wait, and having to wait unexpectedly when a task is interrupted. Participants' waiting-related behavioural and emotional reactions were coded. Parents rated their children's ADHD symptoms and delay aversion. Our findings revealed that the associations between ADHD symptoms and waiting-related responses were comparable in both UK and HK samples. This suggests that the core psychological characteristics of ADHD, particularly in relation to waiting behaviours, may exhibit similarity across cultural contexts. Future research can extend this cross-cultural analysis to other ADHD-related psychological domains and explore additional cultural settings.

The reverse congruency effect elicited by eye-gaze as a function of attention-deficit/hyperactivity disorder symptoms

Individuals diagnosed with attention deficit/hyperactivity disorder (ADHD) have been found to have impairments in multiple aspects of social cognition, thus including the attentional processing of socially relevant stimuli such as eye-gaze. However, to date, it remains unclear whether only the social-specific but not the domain-general directional components, elicited by eye-gaze are affected by ADHD symptomatology. To address this issue, the present study aimed to investigate the impact of ADHD-like traits on the social-specific attentional processing of eye-gaze. To this purpose, we conducted an online experiment with a sample of 140 healthy undergraduate participants who completed two self-reported questionnaires designed to assess ADHD-like traits, and a social variant of an interference spatial task known to effectively isolate the social-specific component of eye-gaze. To make our research plan transparent, our hypotheses, together with the plans of analyses, were registered before data exploration. Results showed that while the social-specific component of eye-gaze was evident in the sample, no significant correlation was found between this component and the measured ADHD-like traits. These results appear to contradict the intuition that the attentional processing of the social-specific components of eye-gaze may be impaired by ADHD symptomatology. However, further research involving children and clinical populations is needed in order to clarify this matter.

A transdiagnostic examination of cognitive heterogeneity in children and adolescents with neurodevelopmental disorders

Children and adolescents with neurodevelopmental disorders demonstrate extensive cognitive heterogeneity that is not adequately captured by traditional diagnostic systems, emphasizing the need for alternative assessment and classification techniques. Using a transdiagnostic approach, a retrospective cohort study of cognitive functioning was conducted using a large heterogenous sample (n = 1529) of children and adolescents 7 to 18 years of age with neurodevelopmental disorders. Measures of short-term memory, verbal ability, and reasoning were administered to participants with attention-deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), comorbid ADHD/ASD, and participants without neurodevelopmental disorders (non-NDD) using a 12-task, web-based neurocognitive testing battery. Unsupervised machine learning techniques were used to create a self-organizing map, an artificial neural network, in conjunction with k-means clustering to identify data-driven subgroups. The study aims were to: 1) identify cognitive profiles in the sample using a data-driven approach, and 2) determine their correspondence with traditional diagnostic statuses. Six clusters representing different cognitive profiles were identified, including participants with varying forms of cognitive impairment. Diagnostic status did not correspond with cluster-membership, providing evidence for the application of transdiagnostic approaches to understanding cognitive heterogeneity in children and adolescents with neurodevelopmental disorders. Additionally, the findings suggest that many typically developing participants may have undiagnosed learning difficulties, emphasizing the need for accessible cognitive assessment tools in school-based settings.

Mental disorders in former street-working boys

The continuity of mental disorders in street-working children is rarely studied. This study therefore investigated homotypic continuity, recurrence of the same disorder, and heterotypic continuity, when a new disorder follows on the previous, of mental disorders from childhood to adulthood in street-working boys from Duhok City, Kurdistan Region of Iraq. Mental disorders were assessed by structured diagnostic interviews in 40 street-working boys in 2004-2005 and again in 2021, when the participants' mean ages were 12.1 (SD 1.8) and 29.7 (SD 2.3), respectively. Mental disorders were common; 24 participants (60%) satisfied the criteria for at least one diagnosis at baseline and 28 (70%) at follow-up. Comorbidity increased from 1.2 (SD 1.4) disorders initially to 2.5 (SD 1.8) at follow-up. Only anxiety disorders showed homotypic continuity. Depressive disorders exhibited the greatest increase over time whereas externalizing disorders exhibited a decreasing tendency. The number of mental disorders in adulthood was related to the number of mental disorders in childhood but not to the number of childhood traumas experienced, having previously worked for more than two hours per day, having worked for over two years on the streets, or having at least one dead parent as a child. Parental ratings on the Child Behaviour Check List (CBCL) from childhood were also unrelated to the number of adult disorders. More longitudinal studies with bigger samples of both genders are needed to fully evaluate the continuity of mental disorders in street-working children and to determine whether the number of mental disorders in childhood is a stronger predictor of being mentally disordered in adult life than psychosocial risk factors or experiences of internalizing or externalizing symptoms in childhood.

Is Attention-Deficit/Hyperactivity Disorder (ADHD) a Dimension or a Category? What Does the Relationship Between ADHD Traits and Psychosocial Quality of Life Tell Us?

OBJECTIVE

The question of whether attention-deficit/hyperactivity disorder (ADHD) is a discrete category or a continuous dimension remains clinically relevant. We report the first examination of this question from the viewpoint of the relationship between ADHD traits and psychosocial quality of life (QoL), and whether the level of QoL declines markedly around a certain high ADHD trait range suggestive of a categorical boundary.

METHODS

Parents/caregivers of 1,967 schoolchildren aged 6 to 11 from the general population completed the Pediatric Quality of Life Inventory and the ADHD-Rating Scale IV. Piecewise linear and non-linear regression analyses were performed.

RESULTS

No evidence for a non-linear association or an abrupt change in the rate of decrease in QoL was observed in the high end of the ADHD traits continuum. Instead, the relationship was consistent with linearity.

CONCLUSION

Psychosocial QoL gradually declines in a linear manner as ADHD trait levels increase providing further support for a dimensional model.

Validation of the Self-Report Version of the German Strengths and Weaknesses of ADHD Symptoms and Normal Behavior Scale (SWAN-DE-SB)

Adults with attention-deficit/hyperactivity disorder (ADHD) experience impairing levels of inattention and/or hyperactivity-impulsivity, while individuals without ADHD experience these symptoms to a lesser extent. Yet, ADHD self-report scales so far hardly captured continuous distributions across the general population. In addition, they focused on weaknesses and ignored strengths. To address these shortcomings, we present here the Strengths and Weaknesses of ADHD and Normal-Behavior Scale Self-Report (SWAN-DE-SB). The normal distribution of the data collected and the scale's internal consistency, and factorial and convergent validity were assessed using data from a general population sample. Its clinical utility was evaluated by comparing scores from a clinical sample and a sample of individuals without ADHD and by calculating optimal cut-off values for specificity and sensitivity. The SWAN-DE-SB demonstrated normal distribution of the data collected, high internal consistency, and factorial and convergent validity. It reliably discriminated individuals with and without ADHD, with high specificity and sensitivity. It should therefore be considered a psychometrically convincing measure to assess strengths and weaknesses of ADHD symptoms and normal behavior in clinical and general population samples.

From Maltreatment to Psychiatric Disorders in Childhood and Adolescence: The Relevance of Emotional Maltreatment

Different forms of maltreatment are thought to incur a cumulative and non-specific toll on mental health. However, few large-scale studies draw on psychiatric diagnoses manifesting in early childhood and adolescence to identify sequelae of differential maltreatment exposures, and emotional maltreatment, in particular. Fine-grained multi-source dimensional maltreatment assessments and validated age-appropriate clinical interviews were conducted in a sample of N = 778 3 to 16-year-olds. We aimed to (a) substantiate known patterns of clinical outcomes following maltreatment and (b) analyse relative effects of emotional maltreatment, abuse (physical and sexual), and neglect (physical, supervisory, and moral-legal/educational) using structural equation modeling. Besides confirming known relationships between maltreatment exposures and psychiatric disorders, emotional maltreatment exerted particularly strong effects on internalizing disorders in older youth and externalizing disorders in younger children, accounting for variance over and above abuse and neglect exposures. Our data highlight the toxicity of pathogenic relational experiences from early childhood onwards, urging researchers and practitioners alike to prioritize future work on emotional maltreatment.

Understanding divergence: Placing developmental neuroscience in its dynamic context

Neurodevelopment is not merely a process of brain maturation, but an adaptation to constraints unique to each individual and to the environments we co-create. However, our theoretical and methodological toolkits often ignore this reality. There is growing awareness that a shift is needed that allows us to study divergence of brain and behaviour across conventional categorical boundaries. However, we argue that in future our study of divergence must also incorporate the developmental dynamics that capture the emergence of those neurodevelopmental differences. This crucial step will require adjustments in study design and methodology. If our ultimate aim is to incorporate the developmental dynamics that capture how, and ultimately when, divergence takes place then we will need an analytic toolkit equal to these ambitions. We argue that the over reliance on group averages has been a conceptual dead-end with regard to the neurodevelopmental differences. This is in part because any individual differences and developmental dynamics are inevitably lost within the group average. Instead, analytic approaches which are themselves new, or simply newly applied within this context, may allow us to shift our theoretical and methodological frameworks from groups to individuals. Likewise, methods capable of modelling complex dynamic systems may allow us to understand the emergent dynamics only possible at the level of an interacting neural system.

Inattention symptom severity and cognitive processes in children at risk of ADHD: the moderating role of separation anxiety

Impairments in cognitive processes and their associations with dimensional measures of inattention, hyperactivity-impulsivity and anxiety were examined in children at risk of Attention-Deficit Hyperactivity Disorder. Children referred by teachers for exhibiting ADHD-type problems (n = 116; 43 meeting full diagnostic criteria for ADHD; 4-8 years) completed computerized tasks measuring episodic memory, response inhibition, visuomotor control and sustained attention, while parents were interviewed (DAWBA) to assess ADHD and anxiety symptoms. Of the 116 children assessed, 72% exhibited impaired cognitive processes; 47% had impaired visuomotor control, 37% impaired response inhibition, and 35% had impaired episodic memory. Correlational and hierarchical regression analyses using our final analytic sample (i.e., children who completed all cognitive tasks and a vocabulary assessment, n = 114) showed that poorer task performance and greater within-subject variability were significantly associated with more severe inattention symptoms but not with hyperactivity-impulsivity severity. Symptoms of separation anxiety, which were reported in over half of the sample, moderated associations between inattention and episodic memory, and between inattention and inhibition. Only children without separation anxiety showed significant correlations between ADHD symptoms and poor performance. However, separation anxiety had no moderating effect on associations between inattention and visuomotor control or sustaining attention. Children exhibiting signs of ADHD show impairments across a range of cognitive tasks. Further research to improve our understanding of these processes may be useful in the development of early interventions. Our results suggest that separation anxiety should be taken into account when considering interventions to address emerging neuropsychological deficits associated with this disorder.

The Relationship Between Early Term Birth and the Risk of Later Childhood Mental Disorders Within a Pregnancy Cohort

This study examines whether gestational age, birth weight, and early term birth is associated with childhood mental disorders in 342 pregnant women recruited at less than 20 weeks gestation and were then followed up until 4 years postpartum, including 93 children born at early term. Women were assessed at recruitment using the Structured Clinical Interview for DSM. At 4 years of age their children were assessed using the Preschool Age Psychiatric Assessment (PAPA) and the Child Behavior Checklist (CBCL). This study found earlier birth predicted an increased risk for anxiety disorders and demonstrated a significant interaction between gestational age and lower birthweight. The risk for ADHD increased with lower gestational age independent of birthweight. In contrast, gestational age was not associated with Oppositional Defiant Disorder, Conduct Disorder, internalizing or externalizing symptoms. These findings highlight the important differences in the association of early term birth and vulnerability for specific mental disorders.

Prospective associations between ADHD symptoms and physical conditions from early childhood to adolescence: a population-based longitudinal study

BACKGROUND

The co-occurrence between attention-deficit hyperactivity disorder (ADHD) and physical conditions is frequent but often goes unrecognised. Most available evidence on the links between ADHD and physical conditions relies on cross-sectional studies. Understanding temporal sequences of associations is key to inform appropriate treatment and preventive strategies. We aimed to assess possible longitudinal associations between ADHD symptoms and a broad range of physical conditions, adjusting for several confounding factors.

METHODS

Participants came from the population-based Quebec Longitudinal Study of Child Development. Participants were selected from the Quebec Birth Registry, recruited between October, 1997, and July, 1998, from the province of Quebec, Canada, and followed up in early childhood (n=2120; age 5 months-5 years), middle childhood (n=1750; age 6-12 years), and adolescence (n=1573; age 13-17 years). Main outcome measures included ADHD symptom severity and physical conditions, which were reported by the person most knowledgeable of the child in early childhood, by teachers in middle childhood, and self-reported in adolescence. Multivariable regression analyses were conducted to study the prospective associations between ADHD symptoms and later physical conditions, and physical conditions and later ADHD symptoms, adjusting for multiple confounders.

FINDINGS

We found several prospective associations between ADHD symptoms and physical conditions including asthma, high BMI (≥1 SD above the mean), epilepsy, dental caries, acute infections, injuries, and sleep problems. After adjusting for key confounding factors, several associations remained: ADHD symptoms in early childhood were associated with later high BMI during middle childhood (odds ratio [OR] 1·19 [95% CI 1·05-1·35]) and adolescence (OR 1·14 [1·01-1·29]), and with unintentional injuries during adolescence (OR 1·10 [1·01-1·21]). ADHD symptoms in middle childhood were significantly associated with later dental caries during adolescence (OR 1·10 [1·01-1·20]). Unintentional injuries in early childhood were associated with later ADHD symptoms in middle childhood (standardised mean difference [SMD] 0·15 [0·05-0·24]) and adolescence (SMD 0·13 [0·04-0·23]), and restless legs syndrome symptoms in middle childhood were associated with later ADHD symptoms in adolescence (SMD 0·15 [0·05-0·25]).

INTERPRETATION

Our results point to the need to carefully monitor children with ADHD in early or middle childhood for several physical conditions, and to monitor children with particular physical conditions for ADHD symptoms. Our study also calls for policies to promote more integrated health-care systems for children with complex mental and physical needs, bridging the current gap between mental and physical health-care services.

FUNDING

Québec Government's Ministry of Health, Ministry of Education, and Ministry of Family Affairs; The Lucie and André Chagnon Foundation; the Robert-Sauvé Research Institute of Health and Safety at Work; the Québec Statistics Institute; the Fonds de Recherche du Québec-Santé; the Fonds de Recherche du Québec-Societé et Culture; Canada's Social Science and Humanities Research Council; the Canadian Institutes of Health Research, the Sainte-Justine Research Center; and the French National Research Agency.

TRANSLATION

For the French translation of the abstract see Supplementary Materials section.

The dimensional structure of internalizing psychopathology: Relation to diagnostic categories

Recent approaches aim to represent the dimensional structure of psychopathology, but relatively little research has rigorously tested sub-dimensions within internalizing psychopathology. This study tests pre-registered models of the dimensional structure of internalizing psychopathology, and their relations with current and lifetime depressive and anxiety disorders diagnostic data, in adult samples harmonized across three sites (n=427). Across S-1 bifactor and hierarchical models, we found converging evidence for both general and specific internalizing dimensions. Depression, generalized anxiety disorder (GAD), social anxiety disorder (SAD), and panic attacks were all associated with a general internalizing factor that we posit primarily represents motivational anhedonia. GAD was also associated with a specific anxious apprehension factor, and SAD with specific anxious apprehension and low positive affect factors. We suggest that dimensional approaches capturing shared and specific internalizing symptom facets more accurately describe the structure of internalizing psychopathology and provide useful alternatives to categorical diagnoses to advance clinical science.

The neuroanatomical substrates of autism and ADHD and their link to putative genomic underpinnings

BACKGROUND

Autism spectrum disorders (ASD) are neurodevelopmental conditions accompanied by differences in brain development. Neuroanatomical differences in autism are variable across individuals and likely underpin distinct clinical phenotypes. To parse heterogeneity, it is essential to establish how the neurobiology of ASD is modulated by differences associated with co-occurring conditions, such as attention-deficit/hyperactivity disorder (ADHD). This study aimed to (1) investigate between-group differences in autistic individuals with and without co-occurring ADHD, and to (2) link these variances to putative genomic underpinnings.

METHODS

We examined differences in cortical thickness (CT) and surface area (SA) and their genomic associations in a sample of 533 individuals from the Longitudinal European Autism Project. Using a general linear model including main effects of autism and ADHD, and an ASD-by-ADHD interaction, we examined to which degree ADHD modulates the autism-related neuroanatomy. Further, leveraging the spatial gene expression data of the Allen Human Brain Atlas, we identified genes whose spatial expression patterns resemble our neuroimaging findings.

RESULTS

In addition to significant main effects for ASD and ADHD in fronto-temporal, limbic, and occipital regions, we observed a significant ASD-by-ADHD interaction in the left precentral gyrus and the right frontal gyrus for measures of CT and SA, respectively. Moreover, individuals with ASD + ADHD differed in CT to those without. Both main effects and the interaction were enriched for ASD-but not for ADHD-related genes.

LIMITATIONS

Although we employed a multicenter design to overcome single-site recruitment limitations, our sample size of N = 25 individuals in the ADHD only group is relatively small compared to the other subgroups, which limits the generalizability of the results. Also, we assigned subjects into ADHD positive groupings according to the DSM-5 rating scale. While this is sufficient for obtaining a research diagnosis of ADHD, our approach did not take into account for how long the symptoms have been present, which is typically considered when assessing ADHD in the clinical setting.

CONCLUSION

Thus, our findings suggest that the neuroanatomy of ASD is significantly modulated by ADHD, and that autistic individuals with co-occurring ADHD may have specific neuroanatomical underpinnings potentially mediated by atypical gene expression.

Mechanisms of cognitive disinhibition explain individual differences in adult attention deficit hyperactivity disorder traits

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) in adults is strongly associated with psychiatric comorbidity and functional impairment. Here, we aimed to use a newly developed online cognitive battery with strong psychometric properties for measuring individual differences in three cognitive mechanisms proposed to underlie ADHD traits in adults: 1) attentional control - the ability to mobilize cognitive resources to stop a prepotent motor response; 2) information sampling/gathering - adequate sampling of information in a stimulus detection task prior to making a decision; and 3) shifting - the ability to adapt behavior in response to positive and negative contingencies.

METHODS

This cross-sectional and correlational study recruited 650 adults (330 males) aged 18-69 years (M = 33.06; MD = 31.00; SD = 10.50), with previously diagnosed ADHD (n = 329) and those from the general community without a history of ADHD (n = 321). Self-report measures of ADHD traits (i.e., inattention/disorganization, impulsivity, hyperactivity) and the cognitive battery were completed online.

RESULTS

Latent class analysis, exploratory structural equation modeling and factor mixture modeling revealed self-reported ADHD traits formed a unidimensional and approximately normally distributed phenotype. Bayesian structural equation modeling demonstrated that all three mechanisms measured by the cognitive battery, explained unique, incremental variance in ADHD traits, with a total of 15.9% explained in the ADHD trait factor.

CONCLUSIONS

Attentional control and shifting, as well as the less researched cognitive process of information gathering, explain individual difference variance in self-reported ADHD traits with potential to yield genetic and neurobiological insights into adult ADHD.

Exploring neural heterogeneity in inattention and hyperactivity

Inattention and hyperactivity are cardinal symptoms of Attention Deficit Hyperactivity Disorder (ADHD). These characteristics have also been observed across a range of other neurodevelopmental conditions, such as autism and dyspraxia, suggesting that they might best be studied across diagnostic categories. Here, we evaluated the associations between inattention and hyperactivity behaviours and features of the structural brain network (connectome) in a large transdiagnostic sample of children (Centre for Attention, Learning, and Memory; n = 383). In our sample, we found that a single latent factor explains 77.6% of variance in scores across multiple questionnaires measuring inattention and hyperactivity. Partial Least-Squares (PLS) regression revealed that variability in this latent factor could not be explained by a linear component representing nodewise properties of connectomes. We then investigated the type and extent of neural heterogeneity in a subset of our sample with clinically-elevated levels of inattention and hyperactivity. Multidimensional scaling combined with k-means clustering revealed two neural subtypes in children with elevated levels of inattention and hyperactivity (n = 232), differentiated primarily by nodal communicability-a measure which demarcates the extent to which neural signals propagate through specific brain regions. These different clusters had similar behavioural profiles, which included high levels of inattention and hyperactivity. However, one of the clusters scored higher on multiple cognitive assessment measures of executive function. We conclude that inattention and hyperactivity are so common in children with neurodevelopmental difficulties because they emerge through multiple different trajectories of brain development. In our own data, we can identify two of these possible trajectories, which are reflected by measures of structural brain network topology and cognition.

Sex differences in conduct and emotional outcomes for young people with hyperactive/inattentive traits and social communication difficulties between 9 and 16 years of age: a growth curve analysis

BACKGROUND

The purpose of this paper is to identify the trajectory of conduct and emotional problems for young people within the general population at four time points (between 9 years 7 months and 16 years 6 months), investigate their relationship with hyperactive/inattentive traits and explore the moderating effect of autistic social traits (ASTs).

METHODS

Data from 9305 individuals involved in The Avon Longitudinal Study of Parents and Children (ALSPAC) study were included. Conduct and emotional problems and hyperactive/inattentive traits were measured by the Strengths and Difficulties Questionnaire. ASTs were assessed using the Social Communication Disorder Checklist. Individual trajectories for conduct and emotional problems were identified via growth curve modelling. Hyperactive/inattentive traits were included within the growth curve model as a time-varying covariate to determine their effect on these outcomes. Finally, participants were split into two groups (below and above clinical threshold ASTs Groups) and multi-group invariance testing was conducted on the data to identify the moderating effect of ASTs on the relationship between hyperactive/inattentive traits and outcomes (i.e. conduct and emotional problems).

RESULTS

Hyperactive/inattentive traits were associated with higher rates of conduct and emotional problems for both boys and girls. The presence of ASTs moderated these relationships for boys, but not for girls, by increasing the risk of boys with hyperactive/inattentive traits developing greater conduct and emotional problems.

CONCLUSIONS

These findings underscore the importance of identifying hyperactive/inattentive traits and ASTs in young people and addressing the increased risk of conduct and emotional problems. Research and clinical implications are explored.

Low Doses of Melatonin to Improve Sleep in Children with ADHD: An Open-Label Trial

OBJECTIVE

Only a few studies assessing the sleep effects of low doses of melatonin (aMT) have been performed in the past, most of them in adults, and only one in subjects with attention-deficit/hyperactivity disorder (ADHD). The aim of this study was to provide evidence of the changes induced by aMT doses as low as 1 mg in the sleep pattern of pediatric patients with ADHD under treatment with methylphenidate (MPH).

METHODS

Children and adolescents (7-15 years) with ADHD who were receiving extended-release MPH were recruited. A seven-week sleep diary was collected prior to starting a four-week treatment with 1 mg of aMT (30 min before bedtime). Seven-day actigraphic assessments of sleep were performed before and after treatment.

RESULTS

Twenty-seven patients (17 males, 62.96%) participated in the study, who had been receiving MPH for 1.57 (1.11) months. A significant increase in sleep duration (TST) was observed after one month of treatment (463 (49) min to 485 (41) min; p < 0.040), with nonsignificant improvements in sleep-onset latency (SOL), nocturnal awakenings, or sleep efficiency. Only minor adverse effects were reported.

CONCLUSION

Low doses of melatonin (1 mg) are able to increase TST in children and adolescents with ADHD receiving treatment with psychostimulants, with an adequate tolerability profile. Further placebo-controlled trials adjusting the time of aMT administration to the individual circadian profile should explore the effects of low doses of this hormone to shorten SOL in this population of patients.

Generalizable prediction of childhood ADHD symptoms from neurocognitive testing and youth characteristics

Childhood attention-deficit/hyperactivity disorder (ADHD) symptoms are believed to result from disrupted neurocognitive development. However, evidence for the clinical and predictive value of neurocognitive assessments in this context has been mixed, and there have been no large-scale efforts to quantify their potential for use in generalizable models that predict individuals' ADHD symptoms in new data. Using data drawn from the Adolescent Brain Cognitive Development Study (ABCD), a consortium that recruited a diverse sample of over 10,000 youth (ages 9-10 at baseline) across 21 U.S. sites, we develop and test cross-validated machine learning models for predicting youths' ADHD symptoms using neurocognitive abilities, demographics, and child and family characteristics. Models used baseline demographic and biometric measures, geocoded neighborhood data, youth reports of child and family characteristics, and neurocognitive tests to predict parent- and teacher-reported ADHD symptoms at the 1-year and 2-year follow-up time points. Predictive models explained 15-20% of the variance in 1-year ADHD symptoms for ABCD Study sites that were left out of the model-fitting process and 12-13% of the variance in 2-year ADHD symptoms. Models displayed high generalizability across study sites and trivial loss of predictive power when transferred from training data to left-out data. Features from multiple domains contributed meaningfully to prediction, including neurocognition, sex, self-reported impulsivity, parental monitoring, and screen time. This work quantifies the information value of neurocognitive abilities and other child characteristics for predicting ADHD symptoms and provides a foundational method for predicting individual youths' symptoms in new data across contexts.

The EPIDIA4Kids protocol for a digital epidemiology study on brain functioning in children, based on a multimodality biometry tool running on an unmodified tablet

Introduction

Neurodevelopment and related mental disorders (NDDs) are one of the most frequent disabilities among young people. They have complex clinical phenotypes often associated with transnosographic dimensions, such as emotion dysregulation and executive dysfunction, that lead to adverse impacts in personal, social, academic, and occupational functioning. Strong overlap exists then across NDDs phenotypes that are challenging for diagnosis and therapeutic intervention. Recently, digital epidemiology uses the rapidly growing data streams from various devices to advance our understanding of health's and disorders' dynamics, both in individuals and the general population, once coupled with computational science. An alternative transdiagnostic approach using digital epidemiology may thus better help understanding brain functioning and hereby NDDs in the general population.

Objective

The EPIDIA4Kids study aims to propose and evaluate in children, a new transdiagnostic approach for brain functioning examination, combining AI-based multimodality biometry and clinical e-assessments on an unmodified tablet. We will examine this digital epidemiology approach in an ecological context through data-driven methods to characterize cognition, emotion, and behavior, and ultimately the potential of transdiagnostic models of NDDs for children in real-life practice.

Methods and analysis

The EPIDIA4Kids is an uncontrolled open-label study. 786 participants will be recruited and enrolled if eligible: they are (1) aged 7 to 12 years and (2) are French speaker/reader; (3) have no severe intellectual deficiencies. Legal representative and children will complete online demographic, psychosocial and health assessments. During the same visit, children will perform additionally a paper/pencil neuro-assessments followed by a 30-min gamified assessment on a touch-screen tablet. Multi-stream data including questionnaires, video, audio, digit-tracking, will be collected, and the resulting multimodality biometrics will be generated using machine- and deep-learning algorithms. The trial will start in March 2023 and is expected to end by December 2024.

Discussion

We hypothesize that the biometrics and digital biomarkers will be capable of detecting early onset symptoms of neurodevelopment compared to paper-based screening while as or more accessible in real-life practice.

Testing Three New Scoring Methods to Identify Detained Adolescent Girls with Elevated Levels of Callous-Unemotional Traits

Different scoring methods have been proposed to identify adolescents with high levels of callous-unemotional (CU) traits as measured by the Inventory of Callous-Unemotional traits (ICU). This is the first study to scrutinize the usefulness of the normative, empirical, and DSM-5 with Limited Prosocial Emotions (LPE) scoring methods in criminal justice-involved girls (N = 192). Girls (Mage = 15.74) completed the ICU and other self-report questionnaires. A diagnostic interview was used to determine the presence of conduct disorder (CD) and other psychiatric disorders. Official arrest and rearrest data were also collected. The three scoring methods designated girls with (versus without) CU traits who scored higher on various indices of past and future antisocial behavior, exhibited higher rates of (childhood-onset) CD and higher levels of psychopathic traits, and displayed lower levels of agreeableness and conscientiousness. It was only when the normative and empirical scoring methods were applied that girls with CU traits had higher rates of substance use disorders and were less anxious, depressed, and/or neurotic. In a subsample of girls with CD (N = 119), the three scoring methods captured a more severely antisocial subgroup. Other expected group differences emerged, though mainly when the normative scoring method was used. Results provided support for the clinical utility of the three scoring methods but also showed that the normative scoring method most aligns with theoretical expectations. Research is warranted to explore if this normative scoring method serves as a better categorically-defined specifier for CD than the specifier that is incorporated in the DSM-5.

Annual Research Review: Perspectives on progress in ADHD science - from characterization to cause

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.

Sex and gender in neurodevelopmental conditions

Health-related conditions often differ qualitatively or quantitatively between individuals of different birth-assigned sexes and gender identities, and/or with different gendered experiences, requiring tailored care. Studying the moderating and mediating effects of sex-related and gender-related factors on impairment, disability, wellbeing and health is of paramount importance especially for neurodivergent individuals, who are diagnosed with neurodevelopmental conditions with uneven sex/gender distributions. Researchers have become aware of the myriad influences that sex-related and gender-related variables have on the manifestations of neurodevelopmental conditions, and contemporary work has begun to investigate the mechanisms through which these effects are mediated. Here we describe topical concepts of sex and gender science, summarize current knowledge, and discuss research and clinical challenges related to autism, attention-deficit/hyperactivity disorder and other neurodevelopmental conditions. We consider sex and gender in the context of epidemiology, behavioural phenotypes, neurobiology, genetics, endocrinology and neighbouring disciplines. The available evidence supports the view that sex and gender are important contributors to the biological and behavioural variability in neurodevelopmental conditions. Methodological caveats such as frequent conflation of sex and gender constructs, inappropriate measurement of these constructs and under-representation of specific demographic groups (for example, female and gender minority individuals and people with intellectual disabilities) limit the translational potential of research so far. Future research and clinical implementation should integrate sex and gender into next-generation diagnostics, mechanistic investigations and support practices.

The Influence of Diagnostic Labels on the Evaluation of Students: a Multilevel Meta-Analysis

Research suggests that children suffering from different types of disorders (learning disorders, behavioral disorders, or intellectual disabilities) are sometimes evaluated differently simply due to the presence of a diagnostic label. We conducted a multilevel meta-analysis of experimental studies (based on data from 8,295 participants and on 284 effects nested in 60 experiments) to examine the magnitude and robustness of such label effects and to explore the impact of potential moderators (type of evaluation, diagnostic category, expertise, student’s gender, and amount and type of information). We found a moderately negative overall label effect (Hedges’ g = −0.42), which was robust across several types of evaluation, different samples, and different diagnostic categories. There was no indication that expertise and the gender of the child moderated the effect. Presenting participants with only a label yielded the strongest negative effect of g = −1.26, suggesting that the effect was dependent on the amount of information being presented to participants. We conclude that labeling a child can exacerbate negative academic evaluations, behavioral evaluations, evaluations of personality, and overall assessments of the child. Further implications for theory and future research are discussed.

An integrative evolutionary framework for psychopathology

The field of psychopathology is in a transformative phase, and is witnessing a renewed surge of interest in theoretical models of mental disorders. While many interesting proposals are competing for attention in the literature, they tend to focus narrowly on the proximate level of analysis and lack a broader understanding of biological function. In this paper, we present an integrative framework for mental disorders built on concepts from life history theory, and describe a taxonomy of mental disorders based on its principles, the fast-slow-defense model (FSD). The FSD integrates psychopathology with normative individual differences in personality and behavior, and allows researchers to draw principled distinctions between broad clusters of disorders, as well as identify functional subtypes within current diagnostic categories. Simulation work demonstrates that the model can explain the large-scale structure of comorbidity, including the apparent emergence of a general "p factor" of psychopathology. A life history approach also provides novel integrative insights into the role of environmental risk/protective factors and the developmental trajectories of various disorders.

Is S100B Involved in Attention-Deficit/Hyperactivity Disorder (ADHD)? Comparisons with Controls and Changes Following a Triple Therapy Containing Methylphenidate, Melatonin and ω-3 PUFAs

BACKGROUND

Increasing evidence supports a neuroinflammatory basis in ADHD damaging glial function and thereby altering dopaminergic (DA) neurotransmission. Previous studies focusing on the S100B protein as a marker of glial function have shown contradictory results. We conducted a clinical trial to investigate differences in S100B levels between ADHD patients and controls, as well as observe gradual changes in S100B concentrations after a triple therapy (TT) containing methylphenidate (MPH), melatonin (aMT) and omega-3 fatty acids (ω-3 PUFAs).

METHODS

62 medication-naïve children with ADHD (ADHD-G) and 65 healthy controls (C-G) were recruited. Serum S100B was measured at baseline (T0) in ADHD-G/C-G, and three (T3) and six months (T6) after starting TT in the ADHD-G, together with attention scores.

RESULTS

A significant increase in S100B was observed in the ADHD-G vs. C-G. In the ADHD-G, significantly higher S100B values were observed for comparisons between T0-T3 and between T0-T6, accompanied by a significant improvement in attention scores for the same timepoint comparisons. No significant differences were found for S100B between T3-T6.

CONCLUSION

Our results agree with the hypothesis of glial damage in ADHD. Further studies on the link between DA and S100B are required to explain the transient increase in S100B following TT.

The continuum of attention dysfunction: Evidence from dynamic functional network connectivity analysis in neurotypical adolescents

The question of whether attention-related disorders such as attention-deficit/hyperactivity disorder (ADHD) are best understood as clinical categories or as extreme ends of a spectrum is an ongoing debate. Assessing individuals with varying degrees of attention problems and utilizing novel methodologies to assess relationships between attention and brain activity may provide key information to support the spectrum hypothesis. We scanned 91 neurotypical adolescents during rest using functional magnetic resonance imaging. We conducted static and dynamic functional network connectivity (FNC) analysis and correlated findings to behavioral metrics of ADHD, attention problems, and impulsivity. We found that dynamic FNC analysis detects significant differences in large-scale neural connectivity as a function of individual differences in attention and impulsivity that are obscured in static analysis. We show ADHD manifestations and attention problems are associated with diminished Salience Network-centered FNC and that ADHD manifestations and impulsivity are associated with prolonged periods of dynamically hyperconnected states. Importantly, our meta-state analysis results reveal a relationship between ADHD manifestations and exhibiting variable and volatile dynamic behavior such as changing meta-states more often and traveling over a greater dynamic range. These findings in non-clinical adolescents provide support for the continuum model of attention disorders.

Risk-Taking Behaviors in Children with ADHD Compared to Children with Primary Headaches

The study examined the engagement in risk-taking behaviors and their onset in children with attention-deficit/hyperactivity disorder (ADHD) compared with children with primary headaches. Whether ADHD is associated with higher engagement in risk-taking behavior compared with other neurodevelopmental disorders (and not only typical development) has yet to be demonstrated. A sample of 189 children, 10 to 18 years old, undergoing neurological surveillance for ADHD (N = 144) or primary headaches (N = 45) participated in the study. The children and their parents reported the children's engagement in various risk-taking behaviors. The ADHD group reported a higher level of general risk-taking behavior relative to the headache group. The differences remained significant even after controlling for demographic and clinical variables. No differences in the age of onset of risk-taking behaviors were found. It is concluded that risk-taking behavior is more common in children with ADHD under active neurological surveillance than in children followed for primary headaches.

Diagnostic profiles in adolescence and emerging adulthood: Transition patterns and risk factors

INTRODUCTION

Complex diagnostic profiles (i.e., clusters of comorbid disorders) may be present in adolescence with long-lasting effects later in life. Little is known about their developmental transitions to adulthood as well as potential risk factors. This study aimed to identify the diagnostic profiles in adolescence and emerging adulthood, patterns of transitions and risk factors.

MATERIAL AND METHODS

A sample of 1062 Mexican adolescents (43.22% men, M=14.19 years at baseline, SD=1.68) was assessed for psychiatric disorders at adolescence and emerging adulthood. Latent class analysis was used to identify diagnostic profiles. Profile transition was studied using multi-state modeling between the life periods. Logistic regression was utilized to study risk factor influence on profile development in adulthood.

RESULTS

Three diagnostic profiles (i.e., minimal disorder/no-psychopathology; and two clinical profiles: internalizing and externalizing) were identified in both periods. Anxiety disorders were the most frequent psychiatric presentation in adolescence, while depression was the most prevalent disorder in adulthood. More than 15% of participants showed a clinical profile regardless life period. Comorbidity was present in 57% of participants with a clinical psychiatric profile. Finally, common (suicidal behavior) and specific risk factors (sex, parents' education and income) predicted transitions to profiles from adolescence to emerging adulthood.

CONCLUSIONS

Psychiatric disorders are frequently observed adopting a complex diagnostic profile in both adolescence and emerging adulthood. Comorbidity seems to be common in both life periods. Developmental issues and comorbidity should be considered for health service provision and treatment choice.

The effects of bilingualism on cognition and behaviour in individuals with attention deficits: A scoping review

Background

Weaknesses in executive function have persistently been found to be associated with Attention Deficit Hyperactivity Disorder (ADHD), while bilinguals have been argued to show advantages in executive functions. While there has been some research into how bilingualism affects cognitive skills and behaviour in individuals with attention deficits, the question is still very much open. The aim of this systematic review is to gather, synthesise and evaluate existing evidence on how bilingual language experience and attention deficits affect executive function performance and ADHD-related symptoms in children and adults.

Methods

Following PRISMA guidelines, a comprehensive literature search in relevant databases (PsycInfo, PubMed, Scopus, ERIC, Web of Science, EMBASE, MEDLINE, LLBA) was performed using search strings related to attention difficulties/ADHD and bilingualism. All quantitative studies were included that presented original empirical data on the combined effects of bilingualism and attention levels, regardless of age group and methodology. The screening procedure revealed nine relevant studies.

Results

Across the nine identified studies, a total of 2071 participants were tested. Of these, seven studies involved children and two adults. The studies varied considerably with respect to their design and methodology, the targeted executive function skills or behavioural symptoms, as well as their measure of bilingualism and attention levels. Most studies assessed aspects of executive function performance such as interference control, response inhibition, working memory or cognitive flexibility. Three studies looked at the effects of bilingualism on ADHD-related symptoms or ADHD diagnosis. Across the studies, no systematic advantage or disadvantage of bilingualism on cognitive performance or behaviour in people with attention deficits was observed.

Conclusion

The limited number of identified studies provide no consistent evidence that bilingualism alleviates or intensifies attention difficulties in adults or children with ADHD. Based on the current state of research, individuals with ADHD and their families should not be concerned that learning additional languages has a negative impact on functioning or cognitive performance.

Systematic review registration

https://doi.org/10.17605/OSF.IO/PK768.

Translating Big Data to Clinical Outcomes in Anxiety: Potential for Multimodal Integration

PURPOSE OF THE REVIEW

This review describes approaches to research on anxiety that attempt to link neural correlates to treatment response and novel therapies. The review emphasizes pediatric anxiety disorders since most anxiety disorders begin before adulthood.

RECENT FINDINGS

Recent literature illustrates how current treatments for anxiety manifest diverse relations with a range of neural markers. While some studies demonstrate post-treatment normalization of markers in anxious individuals, others find persistence of group differences. For other markers, which show no pretreatment association with anxiety, the markers nevertheless distinguish treatment-responders from non-responders. Heightened error related negativity represents the risk marker discussed in the most depth; however, limitations in measures related to error responding necessitate multimodal and big-data approaches. Single risk markers show limits as correlates of treatment response. Large-scale, multimodal data analyzed with predictive models may illuminate additional risk markers related to anxiety disorder treatment outcomes. Such work may identify novel targets and eventually guide improvements in treatment response/outcomes.

White Matter Microstructure in Attention-Deficit/Hyperactivity Disorder: A Systematic Tractography Study in 654 Individuals

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by age-inappropriate levels of inattention and/or hyperactivity-impulsivity. ADHD has been related to differences in white matter (WM) microstructure. However, much remains unclear regarding the nature of these WM differences and which clinical aspects of ADHD they reflect. We systematically investigated whether fractional anisotropy (FA) is associated with current and/or lifetime categorical diagnosis, impairment in daily life, and continuous ADHD symptom measures.

METHODS

Diffusion-weighted imaging data were obtained from 654 participants (322 unaffected, 258 affected, 74 subthreshold; 7-29 years of age). We applied automated global probabilistic tractography on 18 major WM pathways. Linear mixed-effects regression models were used to examine associations of clinical measures with overall brain and tract-specific FA.

RESULTS

There were significant interactions of tract with all ADHD variables on FA. There were no significant associations of FA with current or lifetime diagnosis, nor with impairment. Lower FA in the right cingulum angular bundle was associated with higher hyperactivity-impulsivity symptom severity (p_{familywise error} = .045). There were no significant effects for other tracts.

CONCLUSIONS

This is the first time global probabilistic tractography has been applied to an ADHD dataset of this size. We found no evidence for altered FA in association with ADHD diagnosis. Our findings indicate that associations of FA with ADHD are not uniformly distributed across WM tracts. Continuous symptom measures of ADHD may be more sensitive to FA than diagnostic categories. The right cingulum angular bundle in particular may play a role in symptoms of hyperactivity and impulsivity.

The 25-Item Ontario Child Health Study Emotional Behavioural Scales-Brief Version (OCHS-EBS-B): Test-Retest Reliability and Construct Validity When Used as Categorical Measures

OBJECTIVE

Child and youth mental health problems are often assessed by parent self-completed checklists that produce dimensional scale scores. When converted to binary ratings of disorder, little is known about their psychometric properties in relation to classifications based on lay-administered structured diagnostic interviews. In addition to estimating agreement, our objective is to test for statistical equivalence in the test-retest reliability and construct validity of two instruments used to classify child emotional, behavioural, and attentional disorders: the 25-item, parent completed Ontario Child Health Study Emotional Behavioural Scales-Brief Version (OCHS-EBS-B) and the Mini International Neuropsychiatric Interview for Children and Adolescents-parent version (MINI-KID-P).

METHODS

This study draws on independent samples (n = 452) and uses the confidence interval approach to test for statistical equivalence. Reliability is based on kappa (κ). Construct validity is based on standardized beta coefficients (β) estimated in structural equation models.

RESULTS

The average differences between the MINI-KID-P and OCHS-EBS-B in κ and β were -0.022 and -0.020, respectively. However, in both instances, criteria for statistical equivalence were met in only 5 of 12 comparisons. Based on κ, between-instrument agreement on the classifications of disorder went from 0.481 (attentional disorder) to 0.721 (emotional disorder) but were substantially higher (0.731 to 0.895, respectively) when corrected for attenuation due to measurement error.

CONCLUSIONS

Although falling short of equivalence, the results suggest on balance that the reliability and validity of the two instruments for classifying child psychiatric disorder assessed by parents are highly comparable. This conclusion is supported by the high levels of agreement between the instruments after correcting for attenuation due to measurement error.

Limited Prosocial Emotions in a Clinical Population of Children and Adolescents: Proposal for Core and Ancillary Characteristics

OBJECTIVE

Limited prosocial emotions (LPE) has been recently incorporated into international classifications as a specifier for conduct disorder in the DSM-5 and for all disruptive behavioural disorders in the ICD-11. The aims of the current work were to determine (a) the accuracy of each of the characteristics used to assess the LPE specifier and (b) whether the manner in which symptoms group together supports the idea of LPE having core characteristics.

METHOD

Trained clinicians conducted interviews and determined LPE characteristics using responses from 74 parent/guardian and child/adolescent participants.

RESULTS

The distribution of LPE characteristics among those participants with LPE (n = 13) was compared to those with only one LPE characteristic (n = 11). The proposal of callous lack of empathy (CLE) and shallow deficient affect (SDA) as core characteristics was supported by strong associations with the presence of the LPE specifier, larger specificity, and sensitivity indices than those for unconcerned about performance and lack of remorse or guilt, as well as by a robust aggregation in a latent class analysis.

CONCLUSIONS

CLE and SDA could be considered as core characteristics of LPE in children and adolescents.

Annual Research Review: The transdiagnostic revolution in neurodevelopmental disorders

Practitioners frequently use diagnostic criteria to identify children with neurodevelopmental disorders and to guide intervention decisions. These criteria also provide the organising framework for much of the research focussing on these disorders. Study design, recruitment, analysis and theory are largely built on the assumption that diagnostic criteria reflect an underlying reality. However, there is growing concern that this assumption may not be a valid and that an alternative transdiagnostic approach may better serve our understanding of this large heterogeneous population of young people. This review draws on important developments over the past decade that have set the stage for much-needed breakthroughs in understanding neurodevelopmental disorders. We evaluate contemporary approaches to study design and recruitment, review the use of data-driven methods to characterise cognition, behaviour and neurobiology, and consider what alternative transdiagnostic models could mean for children and families. This review concludes that an overreliance on ill-fitting diagnostic criteria is impeding progress towards identifying the barriers that children encounter, understanding underpinning mechanisms and finding the best route to supporting them.

Determining stakeholder priorities and core components for school-based identification of mental health difficulties: A Delphi study

Only approximately half of children and young people (CYP) with mental health difficulties access mental health services in England, with under-identification of need as a contributing factor. Schools may be an ideal setting for identifying mental health difficulties in CYP, but uncertainty remains about the processes by which these needs can best be identified and addressed. In this study, we conducted a two-round, three-panel Delphi study with parents, school staff, mental health practitioners, and researchers to inform the development of a program to identify mental health difficulties in primary schools. We aimed to assess and build consensus regarding (a) the aims of such a program, (b) identification model preferences, (c) key features of the identification model, and (d) key features of the implementation model. A total of 54 and 42 participants completed the Round 1 and 2 questionnaires, respectively. In general, responses indicated that all three panels supported the idea of school-based identification of mental health difficulties. Overall, 53 of a possible 99 items met the criteria for inclusion as program core components. Five main priorities emerged, including that (a) the program should identify children experiencing mental health difficulties across the continuum of severity, as well as children exposed to adversity, who are at greater risk of mental health difficulties; (b) the program should train staff and educate pupils about mental health in parallel; (c) parental consent should be obtained on an opt-out basis; (d) the program must include clear mechanisms for connecting identified pupils to care and support; and (e) to maximize implementation success, the program needs to lie within a school culture that values mental health and wellbeing. In highlighting these priorities, our study provides needed stakeholder consensus to guide further development and evaluation of mental health interventions within schools.

The Association of Self-Reported ADHD Symptoms and Sleep in Daily Life of a General Population Sample of School Children: An Inter- and Intraindividual Perspective

Sleep and Attention-Deficit/Hyperactivity Disorder (ADHD) have repeatedly been found to be associated with each other. However, the ecological validity of daily life studies to examine the effect of sleep on ADHD symptoms is rarely made use of. In an ambulatory assessment study with measurement burst design, consisting of three bursts (each 6 months apart) of 18 days each, 70 German schoolchildren aged 10-12 years reported on their sleep quality each morning and on their subjective ADHD symptom levels as well as their sleepiness three times a day. It was hypothesized that nightly sleep quality is negatively associated with ADHD symptoms on the inter- as well as the intraindividual level. Thus, we expected children who sleep better to report higher attention and self-regulation. Additionally, sleepiness during the day was hypothesized to be positively associated with ADHD symptoms on both levels, meaning that when children are sleepier, they experience more ADHD symptoms. No association of sleep quality and ADHD symptoms between or within participants was found in multilevel analyses; also, no connection was found between ADHD symptoms and daytime sleepiness on the interindividual level. Unexpectedly, a negative association was found on the intraindividual level for ADHD symptoms and daytime sleepiness, indicating that in moments when children are sleepier during the day, they experience less ADHD symptoms. Explorative analyses showed differential links of nightly sleep quality and daytime sleepiness, with the core symptoms of inattention and hyperactivity/impulsivity, respectively. Therefore, future analyses should take the factor structure of ADHD symptoms into account.

Characterizing Underlying Cognitive Components of ADHD Presentations and Co-morbid Diagnoses: A Diffusion Decision Model Analysis

OBJECTIVE

To Explore whether subtypes and comorbidities of attention-deficit hyperactivity disorder (ADHD) induce distinct biases in cognitive components involved in information processing.

METHOD

Performance on the Integrated Visual and Auditory Continuous Performance Test (IVA-CPT) was compared between 150 children (aged 7 to 10) with ADHD, grouped by DSM-5 presentation (ADHD-C, ADHD-I) or co-morbid diagnoses (anxiety, oppositional defiant disorder [ODD], both, neither), and 60 children without ADHD. Diffusion decision modeling decomposed performance into cognitive components.

RESULTS

Children with ADHD had poorer information integration than controls. Children with ADHD-C were more sensitive to changes in presentation modality (auditory/visual) than those with ADHD-I and controls. Above and beyond these results, children with ADHD+anxiety+ODD had larger increases in response biases when targets became frequent than children with ADHD-only or with ADHD and one comorbidity.

CONCLUSION

ADHD presentations and comorbidities have distinct cognitive characteristics quantifiable using DDM and IVA-CPT. We discuss implications for tailored cognitive-behavioral therapy.

Increased hair cortisol in mothers of children with ADHD symptoms and psychosocial adversity background

Parents of children with attention deficit hyperactivity disorder (ADHD) have shown high perceived parenting stress. Hence, physiological adjustment processes, involving the hypothalamic-pituitary-adrenal axis, seem possible. We hypothesized that (1) ADHD symptoms of the child predict an increase of maternal hair cortisol concentration (HCC), and (2) presence of psychosocial adversity amplifies the prediction. We analyzed a preschool-aged sample using a longitudinal design (T1, at the children's age of 4 years; T2, 12 months later). 128 mothers and their children participated in the study. To determine HCC of the previous 3 months, the first scalp-near 3 cm hair segment was used. ADHD symptoms of the child were measured using teacher- and parent-report questionnaires and a clinical interview with the mother. The T1 teacher-reported ADHD symptoms score of the child was significantly positively associated with the mother`s T1 and T2 HCC score. In families with high psychosocial adversity, the prediction of an increase in maternal HCC by the teacher-reported ADHD symptoms of child was significantly stronger than in low-adversity families. In presence of psychosocial family adversity, ADHD symptoms of the child predicted an increase in the mother's HCC. As a continuously high cortisol level implicates health risks and might in turn affect parenting resources, the identifying of caregivers at risk through biological markers of stress could be helpful for planning targeted interventions. As our study is the first on this issue, cross-validation is needed.

ADHD and autism symptoms in youth: a network analysis

BACKGROUND

Previous research investigating the overlap between attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (henceforth, autism) symptoms in population samples have relied on latent variable modeling in which averaged scores representing dimensions were derived from observed symptoms. There are no studies evaluating how ADHD and autism symptoms interact at the level of individual symptom items.

METHODS

We aimed to address this gap by performing a network analysis on data from a school survey of children aged 6-17 years old (N = 7,405). ADHD and autism symptoms were measured via parent-report on the Swanson, Nolan, Pelham-IV questionnaire and the Childhood Autism Spectrum test, respectively.

RESULTS

A relatively low interconnectivity between ADHD and autism symptoms was found with only 10.06% of possible connections (edges) between one ADHD and one autism symptoms different than zero. Associations between ADHD and autism symptoms were significantly weaker than those between two symptoms pertaining to the same construct. Select ADHD symptoms, particularly those presenting in social contexts (e.g. 'talks excessively', 'does not wait turn'), showed moderate-to-strong associations with autism symptoms, but some were considered redundant to autism symptoms.

CONCLUSIONS

The present findings indicate that individual ADHD and autism symptoms are largely segregated in accordance with diagnostic boundaries corresponding to these conditions in children and adolescents from the community. These findings could improve our clinical conceptualization of ADHD and autism and guide advancements in diagnosis and treatment.

How much impairment is required for ADHD? No evidence of a discrete threshold

BACKGROUND

A diagnosis of attention-deficit/hyperactivity disorder (ADHD) requires the presence of impairment alongside symptoms above a specific frequency and severity threshold. However, the question of whether that symptom threshold represents anything more than an arbitrary cutoff on a continuum of impairment requires further empirical study. Therefore, we present the first study investigating if the relationship between ADHD symptom severity and functional impairment is nonlinear in a way that suggests a discrete, nonarbitrary symptom level threshold associated with a marked step increase in impairment.

METHODS

Parent reports on the ADHD-Rating Scale (ADHD-RS-IV), the Weiss Functional Impairment Rating Scale (WFIRS-P), and the Strengths and Difficulties Questionnaire were collected in a general population sample of 1st, 2nd, and 3rd graders (N = 1,914-2,044).

RESULTS

Piecewise linear regression analyses and nonlinear regression modeling both demonstrated that the relationship between symptom severity (ADHD-RS-IV total score) and impairment (WFIRS-P mean score) was characterized by a gradual linear increase in impairment with higher symptom severity and no apparent step increase or changing rate of increase in impairment at a certain high ADHD-RS-IV total score level. Controlling for socioeconomic status, sex, and co-occurring conduct and emotional symptoms did not alter these results, though comorbid symptoms had a significant effect on impairment.

CONCLUSIONS

There was no clear evidence for a discrete, nonarbitrary symptom severity threshold with regard to impairment. The results highlight the continued need to consider both symptoms and impairment in the diagnosis of ADHD.

The Benefits and Limitations of Stimulants in Treating ADHD

This chapter focusses on the benefits and limitations of stimulant medications in the treatment of ADHD. We highlight the key similarities and differences between the different stimulants used to treat ADHD and briefly discuss mechanisms of action, pharmacokinetics, and pharmacodynamics. We will discuss some of the political, ethical, and moral discussions about the use of stimulants including a consideration of the treatment of subsyndromal ADHD and the use of stimulants as cognitive enhancers. We review the comparative efficacy and effectiveness between stimulants and non-pharmacological treatments for ADHD, between stimulant classes and formulations and between stimulant and non-stimulant medications. We discuss the effects on core symptoms, common associated symptoms, cognition, and more distal outcomes including quality of life and functioning and issues related to tolerance, tolerability and adverse effects. Looking at the clinical implications of these findings, we discuss the importance of measurement-based care in the treatment of ADHD. Finally, we will look at the benefits and limitations of stimulants across several different populations and clinical subgroups.

Working memory and reaction time variability mediate the relationship between polygenic risk and ADHD traits in a general population sample

Endophenotypes are heritable and quantifiable traits indexing genetic liability for a disorder. Here, we examined three potential endophenotypes, working memory function, response inhibition, and reaction time variability, for attention-deficit hyperactivity disorder (ADHD) measured as a dimensional latent trait in a large general population sample derived from the Adolescent Brain Cognitive Development^SM Study. The genetic risk for ADHD was estimated using polygenic risk scores (PRS) whereas ADHD traits were quantified as a dimensional continuum using Bartlett factor score estimates, derived from Attention Problems items from the Child Behaviour Checklist and Effortful Control items from the Early Adolescent Temperament Questionnaire-Revised. The three candidate cognitive endophenotypes were quantified using task-based performance measures. Higher ADHD PRSs were associated with higher ADHD traits, as well as poorer working memory performance and increased reaction time variability. Lower working memory performance, poorer response inhibition, and increased reaction time variability were associated with more pronounced ADHD traits. Working memory and reaction time variability partially statistically mediated the relationship between ADHD PRS and ADHD traits, explaining 14% and 16% of the association, respectively. The mediation effect was specific to the genetic risk for ADHD and did not generalise to genetic risk for four other major psychiatric disorders. Together, these findings provide robust evidence from a large general population sample that working memory and reaction time variability can be considered endophenotypes for ADHD that mediate the relationship between ADHD PRS and ADHD traits.

Data-driven analysis of gaze patterns in face perception: Methodological and clinical contributions

Gaze patterns during face perception have been shown to relate to psychiatric symptoms. Standard analysis of gaze behavior includes calculating fixations within arbitrarily predetermined areas of interest. In contrast to this approach, we present an objective, data-driven method for the analysis of gaze patterns and their relation to diagnostic test scores. This method was applied to data acquired in an adult sample (N = 111) of psychiatry outpatients while they freely looked at images of human faces. Dimensional symptom scores of autism, attention deficit, and depression were collected. A linear regression model based on Principal Component Analysis coefficients computed for each participant was used to model symptom scores. We found that specific components of gaze patterns predicted autistic traits as well as depression symptoms. Gaze patterns shifted away from the eyes with increasing autism traits, a well-known effect. Additionally, the model revealed a lateralization component, with a reduction of the left visual field bias increasing with both autistic traits and depression symptoms independently. Taken together, our model provides a data-driven alternative for gaze data analysis, which can be applied to dimensionally-, rather than categorically-defined clinical subgroups within a variety of contexts. Methodological and clinical contribution of this approach are discussed.