Parent-young person lived experience of sensory dysregulation in children with tic disorders: a qualitative study

PURPOSE

To understand the breadth of sensory dysregulation on participation in daily tasks for young people with tic disorders, as research identified that sensory dysregulation experiences are broader than the symptoms being assessed.

METHODS

Eighteen semi-structured interviews were conducted with 16 families with children (5-16 years) with tic disorders. Interviews ranged from 45 to 120 min and were transcribed verbatim. Data collected from parents and young people were analysed and coded together. Thematic analysis using inductive and open coding methods was implemented using NVivo.

RESULTS

The impact of sensory dysregulation on daily life may be understood through the higher-order theme: ''sensory, emotions and tics; it's a ticking time bomb'', and three subthemes: (1) we sacrifice and adapt to get daily activities done in the home, (2) my child's experience of the community environment hinders participation, and (3) sensory preferences impact our entire family.

CONCLUSION

Sensory dysregulation experiences impact the entire family's quality of life, yet patient-reported sensory measures do not adequately capture the impact on the family unit and breath of symptoms. A sensory-based measure for children with tics is needed to comprehensively assess sensory dysregulation sensitivities for this population, ensuring patients' needs and effectiveness of therapy can be measured.

Sensory processing abilities and their impact on disease severity in children with attention-deficit hyperactivity disorder

Objectives

Although several studies have shown sensory processing abnormalities in pediatric subjects with attention-deficit hyperactivity disorder (ADHD), there is significant heterogeneity among their results.

Materials and Methods

This study was performed to compare the sensory processing abilities of children and adolescents with and without ADHD aged 6-15 years and to correlate the sensory processing problems in these patients, with the symptom profile and severity of ADHD. While child sensory profile-2 (SP-2) was used to assess, the sensory processing abilities of ADHD patients, revised Connor's parent rating scale revised, Malin's intelligence scale for Indian children, grade level assessment device, and child behavior checklist were used to assess ADHD symptom severity, intelligence, learning, and behavioral problems, respectively.

Results

A total of 66 ADHD patients enrolled (60 boys), 22 (28%), 7 (9%), and 49 (63%) cases were the ADHD-hyperactive-impulsive (ADHD-HI), ADHD-inattentive, and ADHD-combined (ADHD-C) types, respectively, and 33 typically developing controls. The ADHD patients had a significantly low raw score on most of the factors, sections, and response patterns of SP-2 (P < 0.05), but only four and one ADHD patients had auditory and visual processing scores outside the normal clinical range. There was a trend toward higher scores in the children with ADHD-C and ADHD-HI subtypes. There was a moderate negative correlation between hyperactivity/impulsivity T-score and auditory processing scores in the SP (P < 0.05, r = -0.43). We observed a negative correlation, although weak, between visual processing scores and hyperactivity/impulsivity and a positive correlation between the severity of conduct disorder-related problems, oppositional defiant problems, anxiety problems, and auditory as well as tactile processing scores (P < 0.05). In the quadrant score summary, the scores for all four types, that is, sensory sensitivity, low registration, sensation avoiding, and sensation seeking, were significantly more in the ADHD group, as compared to healthy controls.

Conclusion

Sensory processing abilities in ADHD children differ from that of typically developing children when objectively assessed, although most of the ADHD children had scores in the clinically normal range. The sensory processing profile also has an impact on the severity and comorbidity profile of ADHD patients.

Brief Report: Sensory Features Associated with Autism After Controlling for ADHD Symptoms

BACKGROUND

Sensory processing differences are reported both in children with ADHD and in children with autism. Given the substantial overlap between autism and ADHD, the current study examined which sensory features were uniquely predictive of autistic traits after controlling for ADHD symptoms, age, IQ, and sex in a sample of children and adolescents with autism aged 6-17 years.

METHODS

The sample included 61 children and adolescents with autism. The Sensory Profile was used to examine Dunn's quadrant model (seeking, sensitivity, avoiding, registration), ADHD symptoms were measured using hyperactivity and attention problems BASC-2 T-scores, and autistic traits were measured using the AQ.

RESULTS

After controlling for age, IQ, sex, and ADHD symptoms, Dunn's sensitivity quadrant predicted autistic traits.

CONCLUSIONS

Findings provide insight into the phenotype of autism and ADHD. Sensory sensitivity may be unique to autism over and above elevated ADHD symptoms that are commonly seen in this population.

Network-Based Differences in Top-Down Multisensory Integration between Adult ADHD and Healthy Controls-A Diffusion MRI Study

BACKGROUND

Attention-deficit-hyperactivity disorder (ADHD) is a neurodevelopmental disorder neurobiologically conceptualized as a network disorder in white and gray matter. A relatively new branch in ADHD research is sensory processing. Here, altered sensory processing i.e., sensory hypersensitivity, is reported, especially in the auditory domain. However, our perception is driven by a complex interplay across different sensory modalities. Our brain is specialized in binding those different sensory modalities to a unified percept-a process called multisensory integration (MI) that is mediated through fronto-temporal and fronto-parietal networks. MI has been recently described to be impaired for complex stimuli in adult patients with ADHD. The current study relates MI in adult ADHD with diffusion-weighted imaging. Connectome-based and graph-theoretic analysis was applied to investigate a possible relationship between the ability to integrate multimodal input and network-based ADHD pathophysiology.

METHODS

Multishell, high-angular resolution diffusion-weighted imaging was performed on twenty-five patients with ADHD (six females, age: 30.08 (SD: 9.3) years) and twenty-four healthy controls (nine females; age: 26.88 (SD: 6.3) years). Structural connectome was created and graph theory was applied to investigate ADHD pathophysiology. Additionally, MI scores, i.e., the percentage of successful multisensory integration derived from the McGurk paradigm, were groupwise correlated with the structural connectome.

RESULTS

Structural connectivity was elevated in patients with ADHD in network hubs mirroring altered default-mode network activity typically reported for patients with ADHD. Compared to controls, MI was associated with higher connectivity in ADHD between Heschl's gyrus and auditory parabelt regions along with altered fronto-temporal network integrity.

CONCLUSION

Alterations in structural network integrity in adult ADHD can be extended to multisensory behavior. MI and the respective network integration in ADHD might represent the maturational cortical delay that extends to adulthood with respect to sensory processing.

Sensory Processing in Children and Adolescents with Attention Deficit Hyperactivity Disorder

OBJECTIVE

The aim is to assess the sensory processing difficulties in children and adolescents with ADHD.

METHODS

In all, 38 ADHD children of the age group 6-14 years and 34 age- and gender-matched typically developing controls were included in the study. Sensory processing was assessed on Child Sensory Profile-2. The child behavior checklist and Weiss functional impairment rating scale were applied to assess behavioral problems and functional impairments, respectively.

RESULTS

A significantly higher sensory processing difficulties were seen in children with ADHD than typically developing controls. There were positive correlations between the scores of Child sensory profile 2 with internalizing (with Sensitivity p = .036, Avoiding p = .001, and Auditory p = .029) and externalizing T scores (with Seeking p = .031, Movement p = .025, and Visual p = .018) of CBCL and also with scores of Weiss functional impairment rating scale (with Seeking p = .001, Sensitivity p = .019, and Registration p = .045).

CONCLUSIONS

Sensory problems were common in children with ADHD and add to the functional impairments.

Centrality and interhemispheric coordination are related to different clinical/behavioral factors in attention deficit/hyperactivity disorder: a resting-state fMRI study

Eigenvector-Centrality (EC) has shown promising results in the field of Psychiatry, with early results also pertaining to ADHD. Parallel efforts have focused on the description of aberrant interhemispheric coordination in ADHD, as measured by Voxel-Mirrored-Homotopic-Connectivity (VMHC), with early evidence of altered Resting-State fMRI. A sample was collected from the ADHD200-NYU initiative: 86 neurotypicals and 89 participants with ADHD between 7 and 18 years old were included after quality control for motion. After preprocessing, voxel-wise EC and VMHC values between diagnostic groups were compared, and network-level values from 15 functional networks extracted. Age, ADHD severity (Connor's Parent Rating-Scale), IQ (Wechsler-Abbreviated-Scale), and right-hand dominance were correlated with EC/VMHC values in the whole sample and within groups, both at the voxel-wise and network-level. Motion was controlled by censoring time-points with Framewise-Displacement > 0.5 mm, as well as controlling for group differences in mean Framewise-Displacement values. EC was significantly higher in ADHD compared to neurotypicals in the left inferior Frontal lobe, Lingual gyri, Peri-Calcarine cortex, superior and middle Occipital lobes, right inferior Occipital lobe, right middle Temporal gyrus, Fusiform gyri, bilateral Cuneus, right Precuneus, and Cerebellum (FDR-corrected-p = 0.05). No differences were observed between groups in voxel-wise VMHC. EC was positively correlated with ADHD severity scores at the network level (at p-value < 0.01, Inattentive: Cerebellum rho = 0.273; Hyper/Impulsive: High-Visual Network rho = 0.242, Cerebellum rho = 0.273; Global Index Severity: High-Visual Network rho = 0.241, Cerebellum rho = 0.293). No differences were observed between groups for motion (p = 0.443). While EC was more related to ADHD psychopathology, VMHC was consistently and negatively correlated with age across all networks.

Prevalence Models to Support Participation: Sensory Patterns as a Feature of All Children’s Humanity

Purpose

Research about children tends to consider differences from expected patterns problematic, and associates differences with disabilities [e.g., Autism, attention deficit hyperactivity disorder (ADHD)]. When we focus on disabilities and consider differences automatically problematic, we miss the natural variability in the general population. The International Classification of Functioning, Disability and Health (ICF 11) acknowledges that the experience of disability results from interactions between “environmental” and “personal” factors which determine the person’s capacity to participate. The purpose of this study was to examine sensory patterns across a national sample of children in the general population and samples of children with disabilities to investigate the extent to which differences in sensory processing are representative of natural variability rather than automatically problematic or part of a disability.

Materials and Methods

We employed descriptive statistics and chi-square tests to examine sensory processing patterns in children in the general population and autistic children and children with ADHD. We used standardization and validity data from the Sensory Profile 2 to conduct analyses.

Results

Consistent sensory patterns exist across all groups. Children in all groups had different rates of certain patterns.

Conclusion

Since children in all groups have certain sensory patterns, we cannot associate differences with problematic behaviors. Children participating successfully with all sensory patterns might provide insights for universal design that supports participation of all children.

Sensory Processing Abnormalities in Community-Dwelling Older Adults with Cognitive Impairment: A Mixed Methods Study

Mild cognitive impairment (MCI) or dementia often leads to behavioral and psychiatric symptoms of dementia (BPSD). Sensory processing abnormalities may be associated with BPSD. The purpose of this study was to explore relationships among sensory processing, behavior, and environmental features within the homes of people with MCI or dementia. This project used mixed methods to assess participants' sensory processing, care partner perspectives on behaviors, and in situ observations of the home environment. Nine participants with cognitive impairment (MCI n = 8, early dementia = 1) and their care partners were included. Seven participants with cognitive impairment were reported to have abnormal sensory processing. Findings suggest that unique environmental adaptations, tailored to personal and sensory preferences for each participant, were associated with a decreased level of behavioral disruption during the observation periods. Implementing sensory-based approaches to maximize environment adaptation may be beneficial in reducing disruptive behaviors for adults with cognitive impairment.

Comorbid Psychopathology, Challenging Behavior, Sensory Issues, Adaptive Behavior and Quality of Life in Children and Adolescents with Autism Spectrum Disorder

Aim: Comorbid psychopathology refers to having a diagnosis of two or more co-occurring psychological disorders. The current study investigated the differences between children and adolescents with no-mild, moderate and severe comorbid psychopathology in children and adolescents with ASD.Method: Parents of 133 children completed the Autism Spectrum Disorder-Comorbid for Children, Behavior Problems Inventory-Short Form, Pediatric Quality of Life Inventory, Vineland Adaptive Behavior Scales, Social Communication Questionnaire, Short Sensory Profile, and Behavioral/Educational Interventions and Complementary/Alternative Medicine (CAM) Interventions of the Autism Treatment Network Registry Parent Baseline Assessment.Results: A significant difference was found between severity of comorbid psychopathology and all types of challenging behavior and all sensory issues except movement. A small effect size was also found between comorbid psychopathology and quality of life.Conclusion: The findings from this study show significant difficulties associated with those with comorbid psychopathology in ASD in challenging behavior, sensory issues and quality of life.

Efficacy of Sensory Interventions on School Participation of Children With Sensory Disorders: A Systematic Review

Research demonstrates lower school participation in children with sensory disorders. However, the scientific body of evidence supporting existing sensory intervention modalities is difficult to tackle. More specifically, the literature appears poorly organized, with a highly variable terminology, often with nonoverlapping definitions and lack of good keywords classification that would help organize the diversity of approaches. This systematic review organizes the body of evidence for 3 specific approaches (sensory based, sensorimotor, and sensory integration) and questions their efficacy in improving school participation for children with sensory disorders. Two methods were compared: first, a standard systematic review of the literature in 3 databases using appropriate keywords and descriptors, then an original method based on forward and backward citation connections. A total of 28 studies were retrieved, of which only 7 used the standard method for systematic reviews. For sensory-based approaches, the efficacy of weighted-vest varies according to different factors such as the protocol of use. For sensorimotor approaches, the efficacy of therapy balls, air cushions, platform swing, and physical exercise varies according to the child's sensory characteristics. The efficacy of the sensory integration approach remains mixed across studies.

Explaining individual differences in infant visual sensory seeking

Individual differences in infants’ engagement with their environment manifest early in development and are noticed by parents. Three views have been advanced to explain differences in seeking novel stimulation. The optimal stimulation hypothesis suggests that individuals seek further stimulation when they are under‐responsive to current sensory input. The processing speed hypothesis proposes that those capable of processing information faster are driven to seek stimulation more frequently. The information prioritization hypothesis suggests the differences in stimulation seeking index variation in the prioritization of incoming relative to ongoing information processing. Ten‐month‐old infants saw 10 repetitions of a video clip and changes in frontal theta oscillatory amplitude were measured as an index of information processing speed. Stimulus‐locked P1 peak amplitude in response to checkerboards briefly overlaid on the video at random points during its presentation indexed processing of incoming stimulation. Parental report of higher visual seeking did not relate to reduced P1 peak amplitude or to a stronger decrease in frontal theta amplitude with repetition, thus not supporting either the optimal stimulation or the processing speed hypotheses. Higher visual seeking occurred in those infants whose P1 peak amplitude was greater than expected based on their theta amplitude. These findings indicate that visual sensory seeking in infancy is explained by a bias toward novel stimulation, thus supporting the information prioritization hypothesis.

Noli Me Tangere: Social Touch, Tactile Defensiveness, and Communication in Neurodevelopmental Disorders

Tactile defensiveness is a common feature in neurodevelopmental disorders (NDDs). Since the first studies, tactile defensiveness has been described as the result of an abnormal response to sensory stimulation. Moreover, it has been studied how the tactile system is closely linked to socio-communicative development and how the interoceptive sensory system supports both a discriminating touch and an affective touch. Therefore, several neurophysiological studies have been conducted to investigate the neurobiological basis of the development and functioning of the tactile system for a better understanding of the tactile defensiveness behavior and the social touch of NDDs. Given the lack of recent literature on tactile defensiveness, the current study provides a brief overview of the original contributions on this research topic in children with NDDs focusing attention on how this behavior has been considered over the years in the clinical setting.

The Contribution of Sensory Sensitivity to Emotional Lability in Children with ADHD Symptoms

Emotional lability and sensory sensitivity have been shown to contribute to the overall clinical picture in children with attention deficit hyperactivity disorder (ADHD; Dunn & Bennett, 2002; Sobanski et al., 2010). Further, both of these characteristics have been individually demonstrated to contribute to poorer quality of life, increased functional impairment, and poorer treatment response (Anastopoulos et al., 2010; Boterberg & Warreyn, 2016). However, to date, no study has evaluated the relationship among all three of these factors. The current study hypothesized that increased sensory sensitivity would moderate the relationship between hyperactive/impulsive symptoms of ADHD and emotional lability in youth. Results indicate that heightened sensory sensitivity strengthens the relationship between hyperactive/impulsive symptoms of ADHD and emotional lability in children with three or more clinically impairing ADHD symptoms. This dimensional approach was taken in accordance with growing evidence that even children with sub-threshold ADHD experience significant functional impairment and high rates of sensory sensitivity (Hong et al., 2014). These findings suggest that clinicians treating children with ADHD symptoms and emotional lability should consider assessing for sensory sensitivity as integration of multi-sensory techniques or referral to concurrent occupational therapy may significantly improve treatment outcomes and quality of life for these children and their families.

Neural Correlates of Sensory Abnormalities Across Developmental Disabilities

Abnormalities in sensory processing are a common feature of many developmental disabilities (DDs). Sensory dysfunction can contribute to deficits in brain maturation, as well as many vital functions. Unfortunately, while some patients with DD benefit from the currently available treatments for sensory dysfunction, many do not. Deficiencies in clinical practice surrounding sensory dysfunction may be related to lack of understanding of the neural mechanisms that underlie sensory abnormalities. Evidence of overlap in sensory symptoms between diagnoses suggests that there may be common neural mechanisms that mediate many aspects of sensory dysfunction. Thus, the current manuscript aims to review the extant literature regarding the neural correlates of sensory dysfunction across DD in order to identify patterns of abnormality that span diagnostic categories. Such anomalies in brain structure, function, and connectivity may eventually serve as targets for treatment.

The relationship between ADHD traits and sensory sensitivity in the general population

Preliminary studies in children and adults with Attention Deficit Hyperactivity Disorder (ADHD) report both hypo-responsiveness and hyper-responsiveness to sensory stimuli, as well as problems modulating sensory input. As it has been suggested that those with ADHD exist at the extreme end of a continuum of ADHD traits, which are also evident in the general population, we investigated the link between ADHD and sensory sensitivity in the general population. Two online questionnaires measuring ADHD traits and sensory responsivity across various sensory domains were administered to 234 participants. Results showed a highly significant positive correlation between the number of ADHD traits and the frequency of reported sensory processing problems. An increased number of sensory difficulties across all modalities were associated with the level of ADHD. Furthermore, ADHD traits predicted sensory difficulties and exploratory factor analysis revealed a factor that combined ADHD trait and sensory processing items. This is the first study to identify a positive relationship between sensory processing and ADHD traits in the general population. Our results suggest that sensory difficulties could be part of the ADHD phenotype.

Sensory Processing in Children with Autism Spectrum Disorder and/or Attention Deficit Hyperactivity Disorder in the Home and Classroom Contexts

Children with neurodevelopmental disorders often show impairments in sensory processing (SP) and higher functions. The main objective of this study was to compare SP, praxis and social participation (SOC) in four groups of children: ASD Group (n = 21), ADHD Group (n = 21), ASD+ADHD Group (n = 21), and Comparison Group (n = 27). Participants were the parents and teachers of these children who were 5-8 years old (M = 6.32). They completed the Sensory Processing Measure (SPM) to evaluate the sensory profile, praxis and SOC of the children in both the home and classroom contexts. In the home context, the most affected was the ASD+ADHD group. The ADHD group obtained higher scores than the ASD group on the Body Awareness (BOD) subscale, indicating a higher level of dysfunction. The ASD group, however, did not obtain higher scores than the ADHD group on any subscale. In the classroom context, the most affected were the two ASD groups: the ASD+ADHD group obtained higher scores than the ADHD group on the Hearing (HEA) and Social Participation (SOC) subscales, and the ASD group obtained higher scores than the ADHD group on the SOC subscale. Regarding sensory modalities, difficulties in proprioception seem to be more characteristic to the ADHD condition. As for higher-level functioning, social difficulties seem to be more characteristic to the ASD condition. Differences between the two contexts were only found in the ASD group, which could be related to contextual hyperselectivity, an inherent autistic feature. Despite possible individual differences, specific intervention programs should be developed to improve the sensory challenges faced by children with different diagnoses.

Perception in attention deficit hyperactivity disorder

A large body of research demonstrated that individuals with attention deficit hyperactivity disorder (ADHD) suffer from various neuropsychological deficits. In contrast, less is known and only divergent evidence exists on perceptual functions of individuals with ADHD. This is problematic as neuropsychological and perceptual functions are closely interrelated and are often difficult to disentangle in behavioral assessments. This study presents the conduct and results of a systematic literature review on perceptual functions in children and adults with ADHD. This review considers studies using psychophysical methods (objective measurements) and self- and informant reports (subjective measurements). Results indicate that individuals with ADHD have altered perceptual functions in various domains as compared to typically developing individuals. Increased perceptual functions in individuals with ADHD were found with regard to olfactory detection thresholds, whereas reduced perceptual functions were evident for aspects of visual and speech perception. Moreover, individuals with ADHD were found to experience discomfort to sensory stimuli at a lower level than typically developing individuals. Alterations of perceptual functions in individuals with ADHD were shown to be moderated by various factors, such as pharmacological treatment, cognitive functions, and symptom severity. We conclude by giving implications for daily life functioning and clinical practice.

Enjoyment of tactile play is associated with lower food neophobia in preschool children

Previous research has shown that parental reports of food neophobia and tactile sensitivity are associated with lower fruit and vegetable (F/V) intake in children. This study aimed to pilot a behavioral observation measure of tactile play in young children. The primary aim of the study was to see whether children's enjoyment of tactile play was associated with higher F/V consumption, as well as lower food neophobia. Seventy 2- to 5-year-old children (37 males and 33 females) and their parents were recruited through children's centers in the Leicester region of the United Kingdom during July to October 2012. Children's engagement in two tactile play tasks using sticky foods (mashed potatoes and vegetarian gelatin) was observed and rated by both the researcher and parent. Parents were asked to complete a series of questionnaires measuring F/V consumption, food neophobia, and sensory processing. It was found that lower child food neophobia was significantly related to enjoyment of tactile play, whereas child F/V consumption was associated with parental F/V consumption, but not enjoyment of tactile play. The findings strengthen the idea that tactile processing may be associated with the acceptance of food variety, but not the total amount of F/V consumed. Additional research is indicated to determine whether tactile play tasks can be used to lower child food neophobia.

Analysis of the sensory profile in children with Smith-Magenis syndrome

This study systematically assessed sensory processing in 34 children, aged 3-14 years, with Smith-Magenis syndrome (SMS) using the Sensory Profile Caregiver Questionnaire. Scores for the SMS cohort were significantly different from scores of the national sample of children with and without disabilities in all Sensory Profile categories and quadrants (p < .001). No main effects of age or gender were found, but an interaction effect of age by gender was found in Modulation of Sensory Input Affecting Emotional Responses, in which older females presented with the lowest scores. A significant decline over time was found in the Seeking pattern, reflecting increased vulnerability (p < .05). Nonsignificant trends suggest more vulnerabilities for older versus younger children, especially older females. The neurobehavioral phenotype in children with SMS is expanded by this description of sensory processing. How children with SMS experience and respond to everyday sensations informs multidisciplinary team decisions.

Sensory processing in adults with autism spectrum disorders

Unusual sensory processing has been widely reported in autism spectrum disorders (ASDs); however, the majority of research in this area has focused on children. The present study assessed sensory processing in adults with ASD using the Adult/Adolescent Sensory Profile (AASP), a 60-item self-report questionnaire assessing levels of sensory processing in everyday life. Results demonstrated that sensory abnormalities were prevalent in ASD, with 94.4 percent of the ASD sample reporting extreme levels of sensory processing on at least one sensory quadrant of the AASP. Furthermore, analysis of the patterns of sensory processing impairments revealed striking within-group variability in the ASD group, suggesting that individuals with ASD could experience very different, yet similarly severe, sensory processing abnormalities. These results suggest that unusual sensory processing in ASD extends across the lifespan and have implications regarding both the treatment and the diagnosis of ASD in adulthood.

Sex differences in tactile defensiveness in children with ADHD and their siblings

Tactile defensiveness (TD) is a disturbance in sensory processing and is observed in some children with attention-deficit-hyperactivity disorder (ADHD). TD has been examined in male children with ADHD and in children with ADHD without differentiating by sex. As males and females with ADHD may differ in the clinical expression of the disorder and associated deficits, the aim of this study was to examine sex differences in TD in males and females with ADHD. Non-affected siblings were also examined to investigate familiality of TD. The Touch Inventory for Elementary-School-Aged Children was administered to 47 children with ADHD (35 males, 12 females; mean age 9y 8mo [SD 1y 11mo]), 36 non-affected siblings (21 males, 15 females; mean age 8y 10mo [SD 2y 4mo]), and 35 control children (16 males, 19 females; mean age 9y 5mo [SD 6mo]). Results indicated that females with ADHD displayed higher levels of TD than males with ADHD (who did not differ from control males). This suggests that TD is sex specific and may contribute to the identification of ADHD in females, thus improving diagnostic and therapeutic strength in this under-referred group. Non-affected siblings were unimpaired, regardless of sex, which suggests that TD is specific to the disorder and not part of a familial risk for ADHD.