BACKGROUND:Tourette syndrome (TS) and attention-deficit/hyperactivity disorder (ADHD) often co-occur and are linked to emotional and behavioral difficulties. However, their shared and distinct neural underpinnings, particularly in terms of functional connectivity, remain unclear. Here, we assessed how functional connectivity differs across TS and ADHD as well as its association with emotional and behavioral difficulties. METHODS:Resting-state electroencephalography (EEG) was recorded from 137 children with TS (n = 51), ADHD (n = 24), or TS + ADHD (n = 29) or from typically developing control subjects (n = 33). Functional connectivity was computed from source-reconstructed EEG data in five frequency bands (delta, theta, alpha, beta, and gamma). Behavioral and emotional problems were assessed with the Child Behavior Checklist. RESULTS:Both TS and ADHD were independently associated with reduced functional connectivity across different brain regions, with no interaction effect. However, externalizing problems showed a TS by ADHD interaction across three frequency bands, such that distinct patterns of functional connectivity were associated with externalizing problems in children with TS + ADHD, relative to those with either TS or ADHD. CONCLUSIONS:Although TS and ADHD are associated with decreased functional connectivity in different networks, their effects appear additive rather than interactive at the neural level. However, interactions emerged when examining behavioral problems, suggesting that although TS and ADHD contribute independently to brain connectivity disruptions, their combined impact may uniquely influence emotional and behavioral functioning. This fact highlights the need to consider both shared and disorder-specific mechanisms when studying TS and ADHD.
BACKGROUND:Tourette syndrome (TS) is a neurodevelopmental disorder involving chronic motor and phonic tics. Most individuals with TS can suppress their tics for at least a short period of time. Yet, the brain correlates of tic suppression are still poorly understood.METHODS:In the current study, high-density electroencephalography was recorded during a resting-state and a tic suppression session in 72 children with TS. Functional connectivity between cortical regions was assessed in the alpha band (8-13 Hz) using an electroencephalography source connectivity method. Graph theory and network-based statistics were used to assess the global network topology and to identify brain regions showing increased connectivity during tic suppression.RESULTS:Graph theoretical analyses revealed distinctive global network topology during tic suppression, relative to rest. Using network-based statistics, we found a subnetwork of increased connectivity during tic suppression (p < .001). That subnetwork encompassed many cortical areas, including the right superior frontal gyrus and the left precuneus, which are involved in the default mode network. We also found a condition-by-age interaction, suggesting age-mediated increases in connectivity during tic suppression.CONCLUSIONS:These results suggest that children with TS suppress their tics through a brain circuit involving distributed cortical regions, many of which are part of the default mode network. Brain connectivity during tic suppression also increases as youths with TS mature. These results highlight a mechanism by which children with TS may control their tics, which could be relevant for future treatment studies.
Background Comprehensive Behavioral Intervention for Tics (CBIT) is recommended as a first-line treatment for Tourette syndrome in children and adults. While there is strong evidence proving its efficacy, the mechanisms of reduction in tic severity during CBIT are still poorly understood. In a recent study, our group identified a functional brain network involved in tic suppression in children with TS. We reasoned that voluntary tic suppression and CBIT may share some mechanisms and thus we wanted to assess whether functional connectivity during tic suppression was associated with CBIT outcome. Methods Thirty-two children with TS, aged 8 to 13 years old, participated in a randomized controlled trial of CBIT v. a treatment-as-usual control condition. EEG was recorded during tic suppression in all participants at baseline and endpoint. We used a source-reconstructed EEG connectivity pipeline to assess functional connectivity during tic suppression. Results Functional connectivity during tic suppression did not change from baseline to endpoint. However, baseline tic suppression-related functional connectivity specifically predicted the decrease in vocal tic severity from baseline to endpoint in the CBIT group. Supplementary analyses revealed that the functional connectivity between the right superior frontal gyrus and the right angular gyrus was mainly driving this effect. Conclusions This study revealed that functional connectivity during tic suppression at baseline predicted reduction in vocal tic severity. These results suggest probable overlap between the mechanisms of voluntary tic suppression and those of behavior therapy for tics.
Objective: Comprehensive Behavioral Intervention for Tics (CBIT) is a first-line treatment of Tourette syn-drome (TS). However, the brain mechanisms involved in CBIT are poorly understood. Enhanced frontome-sial EEG coherence during a Go/NoGo task has been suggested as a mechanism involved in voluntary tic control. In the current study, we conducted a randomized controlled trial to assess whether EEG coher-ence during a Go/NoGo task was associated with CBIT outcome. Methods: Thirty-two children with TS were randomly assigned to CBIT or to treatment-as-usual (TAU). Treatment outcome was assessed by a blinded evaluator with the Yale Global Tic Severity Scale (YGTSS) and the Clinical Global Impression - Improvement Scale (CGI-I). EEG was recorded during a Go/NoGo task at baseline and endpoint. EEG coherence was computed in the alpha frequency band between a priori selected channel pairs spanning the frontal and motor areas. Results: Tic severity decreased significantly in the CBIT group. However, CBIT did not impact EEG coher-ence and baseline EEG coherence did not predict treatment outcome. Conclusions: Although CBIT was superior to TAU on blinded clinical outcomes, EEG coherence during the Go/NoGo task was not associated with change in tic severity. Significance: The brain processes involved in the inhibition of motor responses do not appear to be involved in CBIT. (c) 2022 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.
Objective: This study evaluated the efficacy of an Integrated Brain, Body, and Social (IBBS) intervention for children with ADHD. Treatment consisted of computerized cognitive remediation training, physical exercises, and a behavior management strategy. Method: Ninety-two children aged 5 to 9 years with ADHD were randomly assigned to 15 weeks of IBBS or to treatment-as-usual. Primary outcome measures included blinded clinician ratings of ADHD symptoms and global clinical functioning. Secondary outcome measures consisted of parent and teacher ratings of ADHD and neurocognitive tests. Results: No significant treatment effects were found on any of our primary outcome measures. In terms of secondary outcome measures, the IBBS group showed significant improvement on a verbal working memory task; however, this result did not survive correction for multiple group comparisons. Conclusion: These results suggest that expanding cognitive training to multiple domains by means of two training modalities does not lead to generalized improvement of ADHD symptomatology.
Background This study integrated an experimental medicine approach and a randomized cross-over clinical trial design following CONSORT recommendations to evaluate a cognitive training (CT) intervention for attention deficit hyperactivity disorder (ADHD). The experimental medicine approach was adopted because of documented pathophysiological heterogeneity within the diagnosis of ADHD. The cross-over design was adopted to provide the intervention for all participants and make maximum use of data. Methods Children (n = 93, mean age 7.3 +/- 1.1 years) with or sub-threshold for ADHD were randomly assigned to CT exercises over 15 weeks, before or after 15 weeks of treatment-as-usual (TAU). Fifteen dropped out of the CT/TAU group and 12 out of the TAU/CT group, leaving 66 for cross-over analysis. Seven in the CT/TAU group completed CT before dropping out making 73 available for experimental medicine analyses. Attention, response inhibition, and working memory were assessed before and after CT and TAU. Results Children were more likely to improve with CT than TAU (27/66 v. 13/66, McNemar p = 0.02). Consistent with the experimental medicine hypotheses, responders improved on all tests of executive function (p = 0.009-0.01) while non-responders improved on none (p = 0.27-0.81). The degree of clinical improvement was predicted by baseline and change scores in focused attention and working memory (p = 0.008). The response rate was higher in inattentive and combined subtypes than hyperactive-impulsive subtype (p = 0.003). Conclusions Targeting cognitive dysfunction decreases clinical symptoms in proportion to improvement in cognition. Inattentive and combined subtypes were more likely to respond, consistent with targeted pathology and clinically relevant heterogeneity within ADHD.
Co-occurring anxiety is common in children with autism spectrum disorder (ASD). However, inconsistencies across parent and child reports of anxiety may complicate the assessment of anxiety in this population. The present study examined parent and child anxiety ratings in children with ASD with and without anxiety disorders and tested the association between parent-child anxiety rating discrepancy and ASD symptom severity. Participants included children aged 8-16 years in three diagnostic groups: ASD with co-occurring anxiety disorders (ASD + Anxiety; n = 34), ASD without co-occurring anxiety disorders (ASD; n = 18), and typically developing healthy controls (TD; n = 50). Parents and children completed ratings of child anxiety using the Multidimensional Anxiety Rating Scale. Patterns of parent and child anxiety ratings differed among the three groups, with parent ratings exceeding child ratings only in the ASD + Anxiety group. Parents reported higher levels of child anxiety in the ASD + Anxiety versus ASD group, whereas children reported comparable levels of anxiety in the two groups. Among children with ASD, ASD symptom severity was positively associated with the degree to which parent ratings exceeded child ratings. Results suggest that children with ASD and co-occurring anxiety disorders endorse some anxiety symptoms but may underreport overall levels of anxiety. In addition, ASD symptom severity might increase discrepancies in parent-child anxiety ratings. These findings suggest a unique and valuable role of child anxiety ratings and suggest that both parent and child anxiety ratings should be considered in light of children's ASD symptom severity and used to guide further assessment. Autism Res 2020, 13: 93-103. © 2019 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: Children with autism spectrum disorder (ASD) commonly experience anxiety; yet, their perceptions of their anxiety might differ from their parents' perceptions. This study found that, while children with ASD and anxiety disorders acknowledge some anxiety, their parents report them as having higher levels of anxiety. Also, child and parent perceptions of anxiety may differ more for children with more severe ASD symptoms. How these findings may guide research and clinical practice is discussed.
ADHD is a common neurodevelopmental disorder characterized by compromised Executive Function (EF). Children with or at high risk for ADHD did computer-presented and physical brain-training exercises designed to promote activity-dependent development enhancement of neural systems supporting EF, aimed at clinically significant symptom reduction.
OBJECTIVE:Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) are hypothesized to occur as a result of cross-reactive antibodies produced in response to group A streptococcal infections. Previous research suggests that immunomodulatory therapies, such as intravenous immunoglobulin (IVIG), may lead to rapid and sustained symptom improvement in patients with PANDAS. METHOD:A total of 35 children meeting criteria for PANDAS and moderate to severe obsessive-compulsive disorder (OCD) were enrolled in a randomized-entry, double-blind, placebo-controlled, 6-week trial of IVIG (1 g/kg/day on 2 consecutive days), followed by optional open-label treatment for nonresponders, with follow-up at 12 and 24 weeks. Primary outcome measures were the Children's Yale-Brown Obsessive Compulsive Scale (CY-BOCS) and the Clinical Global Impressions-Improvement (CGI-I) rating. "Responders" were defined, a priori, by a ≥ 30% decrease in CY-BOCS total score, and a "much" or "very much" improved rating on CGI-I. RESULTS:During the double-blind phase, the mean decrease in CY-BOCS score was 24% ± 31% in the IVIG group (n = 17) and 12% ± 27% in the placebo group (n = 18), with six responders in the IVIG group (35%) versus four (22%) in the placebo group; these differences were not statistically significant. Twenty-four participants met criteria for nonresponse to double-blind infusion and received open-label IVIG at week 6. Among all participants, the mean CY-BOCS improvement from baseline was 55% ± 33% at week 12 and 62% ± 33% at week 24. CONCLUSION:IVIG was safe and well tolerated. Between-group differences were smaller than anticipated, and the double-blind comparison failed to demonstrate superiority of IVIG over placebo. The observed open-label improvements indicate that future trials would benefit from larger sample sizes designed in part to aid in the identification of biomarkers predictive of a positive response to immunotherapy. Future investigations focused on the natural history of PANDAS are also warranted. Clinical trial registration information-Intravenous Immunoglobulin for PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated With Streptococcal Infections); http://clinicaltrials.gov/; NCT01281969ZIAMH002666.
Youth with Tourette syndrome (TS) often exhibit disruptive behaviors. Although improvement data on rating scales support the efficacy of structured psychotherapeutic interventions, there is growing interest in personalized outcome assessments. This report examined parent-nominated target problems (PTPs) as an individualized outcome measure in 48 youth with TS and disruptive behaviors, who participated in one of two randomized psychotherapy trials. At baseline, parents described two primary problems to an independent evaluator who generated a structured narrative for each problem. These narratives were reviewed and updated at endpoint. When rated by five treatment-blind judges, the PTP rating demonstrated excellent reliability and good convergent validity with the Disruptive Behavior Rating Scale (DBRS). The PTP rating exhibited comparable treatment effects to the DBRS, and accounted for additional variance in global treatment outcome. The PTP rating serves a reliable, valid, and sensitive personalized assessment in research trials that provides complementary information to standardized rating scales.
Chronic tic disorders (TD) are consistently found to have high rates of comorbidity with obsessive-compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD). The purpose of this study is to compare the severity of TD only to TD with comorbid OCD or ADHD based on severity of tics, measures of psychopathology and additional comorbid diagnoses. Baseline data from 158 youth with a chronic TD who participated in two longitudinal studies were examined. Fifty-three percent (N = 85) of the youth also met criteria for a diagnosis of OCD, 38.6 % (n = 61) met criteria for ADHD and 24.1 % (N = 38) met criteria for both. Measures of interest addressed severity of tics, symptoms of anxiety, depression, ADHD, psychosocial stress, global functioning and the presence of comorbid diagnoses. Youth with comorbid TD and OCD were characterized by more severe tics, increased levels of depressive and anxious symptoms, heightened psychosocial stress and poorer global functioning. Youth with comorbid TD and ADHD did not differ from those with TD alone on measures of tic severity, but experienced greater psychosocial stress and poorer global functioning. Subjects with comorbid TD and OCD had more internalizing disorders than those without OCD, while those with comorbid ADHD were more likely to meet criteria for oppositional defiant disorder. TD with OCD is a more severe subtype of TD than TD without OCD. TD with ADHD is associated with higher psychosocial stress and more externalizing behaviors. Further research is needed into the underlying relationships between these closely associated conditions.
Objective: The objective of this blinded, prospective, longitudinal study was to determine whether new group A beta hemolytic streptococcal (GABHS) infections are temporally associated with exacerbations of tic or obsessive-compulsive (OC) symptoms in children who met published criteria for pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS). A group of children with Tourette syndrome and/or OC disorder without a PANDAS history served as the comparison (non-PANDAS) group. Method: Consecutive clinical ratings of tic and OC symptom severity were obtained for 31 PANDAS subjects and 53 non-PANDAS subjects. Clinical symptoms and laboratory values (throat cultures and streptococcal antibody titers) were evaluated at regular intervals during a 25-month period. Additional testing occurred at the time of any tic or OC symptom exacerbation. New GABHS infections were established by throat swab cultures and/or recent significant rise in streptococcal antibodies. Laboratory personnel were blinded to case or control status, clinical (exacerbation or not) condition, and clinical evaluators were blinded to the laboratory results. Results: No group differences were observed in the number of clinical exacerbations or the number of newly diagnosed GABHS infections. On only six occasions of a total of 51(12%), a newly diagnosed GABHS infection was followed, within 2 months, by an exacerbation of tic and/or OC symptoms. In every instance, this association occurred in the non-PANDAS group. Conclusions: This study provides no evidence for a temporal association between GABHS infections and tic/OC symptom exacerbations in children who meet the published PANDAS diagnostic criteria. J. Am. Acad. Child Adolesc. Psychiatry, 2011;50(2): 108-118.
Background: The goals of this prospective longitudinal study were to monitor levels of psychosocial stress in children and adolescents with Tourette syndrome (TS) and/or obsessive-compulsive disorder (OCD) compared to healthy control subjects and to examine the relationship between measures of psychosocial stress and fluctuations in tic, obsessive-compulsive (OC), and depressive symptom severity. Methods: Consecutive ratings of tic, OC and depressive symptom severity were obtained for 45 cases and 41 matched healthy control subjects over a two-year period. Measures of psychosocial stress included youth self-report, parental report, and clinician ratings of long-term contextual threat. Structural equation modeling for unbalanced repeated measures was used to assess the temporal sequence of psychosocial stress with the severity of tic, OC and depressive symptoms. Results: Subjects with TS and OCD experienced significantly more psychosocial stress than did the controls. Estimates of psychosocial stress were predictive of future depressive symptoms. Current levels of psychosocial stress were also a significant predictor of future OC symptom severity, but not vice versa. Current OC symptom severity was a predictor of future depressive symptom severity, but not vice versa. Current levels of psychosocial stress and depression were independent predictors of future tic severity, even after controlling for the effect of advancing chronological age. Conclusions: The impact of antecedent psychosocial adversity is greater on future depressive symptoms than for tic and/or OC symptoms. Worsening OC symptoms are also a predictor of future depressive symptoms. Advancing chronological age is robustly associated with reductions in tic severity.
Tourette syndrome (TS) is a childhood neuropsychiatric disorder characterized by motor and vocal tics. Imaging studies found alterations in caudate (Cd) and putamen volumes. To investigate possible alterations in cell populations, postmortem basal ganglia tissue from individuals with TS and normal controls was analyzed by using unbiased stereological techniques. A markedly higher total neuron number was found in the globus pallidus pars interna (GPi) of TS. In contrast, a lower neuron number and density was observed in the globus pallidus pars externa and in the Cd. An increased number and proportion of the GPi neurons were positive for the calcium-binding protein parvalbumin in tissue from TS subjects, whereas lower densities of parvalbumin-positive interneurons were observed in both the Cd and putamen of TS subjects. This change is consistent with a developmental defect in tangential migration of some GABAergic neurons. The imbalance in striatal and GPi inhibitory neuron distribution suggests that the functional dynamics of cortico-striato-thalamic circuitry are fundamentally altered in severe, persistent TS.
Background: The hypothesis; that common infections can modulate the onset and course of tic disorders and early-onset obsessive-compulsive disorder (OCD) in pediatric populations is longstanding. To date, most investigations have focused on the hypothesis of molecular mimicry and humoral immune responses. This study was carried out to investigate whether cytokines associated with, the innate immune response or T cell activation were altered under baseline conditions and during periods of symptom exacerbation.Methods: Forty-six patients with Tourette's syndrome and/or early-onset OCD, aged 7-17 years, and 31 age-matched control subjects participated in a prospective longitudinal study. Ratings of clinical severity and serum were collected at regular intervals, and serum concentrations of 10 cytokines were measured repeatedly.Results: Interleukin-12 and tumor necrosis factor a concentrations at baseline were elevated in patients compared with control subjects. Both of these markers were further increased during periods of symptom exacerbation.Conclusions: These findings suggest that symptom exacerbations are associated with an inflammatory process propagated by systemic and local cytokine synthesis that might involve the central nervous system. We conclude that, in the future, longitudinal studies of children with neuropsychiatric disorders should examine the involvement of innate and T cell immunity.
Background. It has been proposed that infection by group A beta-hemolytic streptococci (GABHS) can trigger acute symptom exacerbations among patients with Tourette's syndrome (TS) or obsessive-compulsive disorder (OCD), via autoimmune mechanisms.Objective. To examine the temporal relationship between newly acquired GABHS infections (and other immunologic indices) and acute exacerbations of tics and obsessive-compulsive symptoms.Methods. Pediatric patients (7-17 years of age) with TS and/or OCD (N = 47) and healthy control subjects (N = 19) were prospectively monitored for newly acquired GABHS infections, nonspecific markers of acute inflammatory responses, and D8/17-reactive cells (a marker of rheumatic fever). Objective monthly ratings of tic and obsessive-compulsive symptom severity were used to determine the timing of symptom exacerbations.Results. The overall rate of acute exacerbations of neuropsychiatric symptoms was 0.56 exacerbations per patient per year. The average rate of new GABHS infections, using a stringent definition, was 0.42 infections per subject per year among patients, compared with 0.28 infections per subject per year for control subjects. The association between symptom exacerbations and new GABHS infections among patients was no greater than that expected on the basis of chance. At baseline, patients demonstrated significantly higher levels of D8/17-reactive cells and neopterin, compared with control subjects, but there was no consistent pattern of change when exacerbation time points were compared with baseline or follow-up time points.Conclusions. The results suggest no clear relationship between new GABHS infections and symptom exacerbations in an unselected group of patients with TS and/or OCD.
Objective The Yale Children's Global Stress Index (YCGSI) is a new clinical rating instrument designed to provide objective global clinician ratings of psychosocial stress in studies of children and adolescents. This study was designed to evaluate the psychometric properties of the YCGSI. Method Independent ratings of clinical severity and psychosocial stress were obtained at two time points separated by 4 months from 33 subjects with Tourette's syndrome (TS) and/or early-onset obsessive-compulsive disorder (OCD), aged 7 to 17 years, and 25 age-matched control subjects. Parents and children were interviewed separately. Multiple measures of stress were obtained including the YCGSI and the Daily Life Stressors Scale (DLSS). Results Data support the interrater reliability and convergent and divergent validity of the YCGSI. At both time points, children and adolescents with TS and OCD had, on average, experienced significantly more psychosocial stress than did the controls. Cross-sectional ratings of tic and obsessive-compulsive symptom severity did not correlate with the YCGSI, but did correlate with self-report ratings of stress on the DLSS. In contrast, ratings on the YCGSI were associated with clinician ratings of depression. Conclusions The YCGSI has acceptable psychometric properties. Children and adolescents with TS and OCD appear to be at increased risk of experiencing higher levels of psychosocial stress and adversities compared with their peers in the community. Future studies need to examine the possible differential contributions of distinctive forms of stress on the intramorbid course of these disorders.
OBJECTIVES The severity of tic and obsessive-compulsive (OC) symptoms varies over time. Consequently, how do we, as clinicians, know when a change in symptom severity occurs that falls outside of the normal range of fluctuation? The goal of this study was to describe the level of symptom severity fluctuation over time and to establish an objective, prospective, and quantitative method for identifying symptom exacerbations in children with Tourette's syndrome, obsessive-compulsive disorder (OCD), or both. A second major aim was to assess whether fluctuations in tic and OC symptom severity covaried with one another. METHOD Monthly consecutive Yale Global Tic Severity Scale and Children's Yale-Brown Obsessive Compulsive Scale scores were prospectively obtained in 64 children diagnosed with Tourette's syndrome and/or OCD for periods ranging from 3 to 39 months. Exacerbation thresholds were estimated by using state-of-the-art bootstrap methods. These thresholds were then independently evaluated by asking two expert clinicians to identify, retrospectively, clinically significant exacerbations based on a review of all available clinical and research records. RESULTS The severity of tic and OC symptoms displayed a high degree of intrasubject variability. Exacerbation thresholds, which incorporated the change score from the previous month and the current symptom score, provided the best agreement with those of expert clinicians. When both tic and OC symptoms were present, they showed a significant degree of covariation. CONCLUSIONS Evidence-based treatments are coming of age. The use of valid, clinician-rated severity scales will likely become a standard part of clinical practice. Bootstrapping methods may provide a quantitative and convenient way to obtain clinically valid thresholds to assess tic and OC symptom exacerbations. This method has the potential to be applied to other symptom domains where exacerbation thresholds are needed.