Electrophysiological predictors of cognitive-behavioral therapy outcome in tic disorders

Behavioural Therapy for tic disorders: a comprehensive review of the literature

INTRODUCTION

Behavioral therapies are recommended as a first-line intervention for Tourette syndrome and persistent motor or phonic tic disorder.

AREAS COVERED

In this review, the authors summarize randomized controlled trials on the comprehensive behavioral intervention for tics (CBIT), habit reversal therapy (HRT), and exposure and response prevention (ERP). Studies of face-to-face treatment, treatment by video conferencing, group treatment, and internet delivered treatment were assessed, as well as evidence of treatment predictors, modifiers, and mediators.

EXPERT OPINION

There is high-quality evidence for face-to-face one-on-one treatment with CBIT, and data suggesting that one-on-one treatment by videoconference provides similar benefit. Limited data on group treatment with CBIT/HRT suggests inferiority to individual treatment, while internet-based CBIT programs appear more beneficial than wait list or psychoeducation. There is one face-to-face one-on-one treatment comparison of ERP to HRT, suggesting equal benefit. Internet-based ERP with minimal therapist support appears effective, although effect sizes are small. One study using behavioral therapy with ERP or HRT found similar benefit to medical treatment with antipsychotics. Data on predictors, modifiers, and mediators of treatment efficacy are emerging. In summary, behavioral therapies are an important treatment modality for tic disorders. Furthermore, important efforts to improve treatment accessibility are underway.

Efficacy of cognitive-behavioral therapy combined with habit reversal training on anxiety disorders in children with Tourette's syndrome

BACKGROUND

Cognitive-behavioral therapy (CBT) and habit reversal training (HRT) have shown application potential in addressing tic symptoms and comorbid psychiatric conditions. Despite their theoretical potential, empirical evidence on their combined efficacy remains limited.

AIM

To evaluate the efficacy of CBT combined with HRT on anxiety disorders in children with Tourette's syndrome (TS).

METHODS

Clinical data of children with TS admitted to our hospital from January 2022 to June 2023 were collected, and the patients were grouped into the conventional therapy (control) group and the CBT combined with HRT group. Baseline characteristics, anxiety scores, tic severity scores, treatment adherence, and parental satisfaction were assessed. Statistical analysis was performed using t-tests, chi-square tests, and correlation analysis.

RESULTS

A total of 136 patients, including 65 patients in the control group and 71 patients in the CBT combined with HRT group, were included. The CBT combined with HRT group showed remarkable improvements compared with the control group. Post-intervention assessment revealed a decrease in anxiety scores from 63.52 ± 1.81 to 40.53 ± 1.64 (t = 2.022, P = 0.045), and the Yale Global Tic Severity Scale total score decreased from 22.14 ± 5.67 to 16.28 ± 4.91 (t = 2.288, P = 0.024). Treatment adherence was significantly higher in the CBT combined with HRT group (85.47 ± 7.62%) compared with the control group (82.32 ± 6.54%; t = 2.596, P = 0.010). Parental satisfaction scores were also higher in the CBT combined with HRT group (8.69 ± 1.77) compared with the control group (7.87 ± 1.92; t = 2.592, P = 0.011).

CONCLUSION

This study demonstrates that CBT combined with HRT significantly reduces anxiety symptoms and tic severity in children with TS, with higher treatment adherence and parental satisfaction. These findings support the potential application of this comprehensive therapeutic approach for TS treatment.

Impacts of ADHD Symptomatology on the Response to Cognitive-Behavioural Therapy with Gilles de la Tourette Syndrome Patients

(1) Background: Gilles de la Tourette Syndrome (TS) is a neurodevelopmental disorder characterized by motor and vocal tics. Attention deficit and hyperactivity disorder (ADHD) is a common comorbidity of TS that adds further impairment. Cognitive-behavioural therapy (CBT) has shown efficacy in treating tics, yet its effectiveness in individuals with TS and comorbid ADHD remains unclear. Also, it is suggested that ADHD characteristics like executive dysfunction and inattention could hinder the response to CBT. This study aims to compare the response to CBT for tics and its maintenance six months post-therapy among TS individuals with and without ADHD symptoms. (2) Methods: In this study, 55 TS participants who completed 14-week CBT for tics were split into high (TS+) or low (TS-) ADHD symptomatology groups. Outcomes were evaluated using the Yale Global Tic Severity Scale (YGTSS) regarding global tic severity and motor and vocal tic frequency post-CBT and at a 6-month follow-up. (3) Results: No significant group difference was found regarding improvements post-CBT (n = 55), nor the maintenance six months later (n = 45). (4) Conclusions: ADHD symptoms may not hinder the response to CBT or its maintenance, suggesting that TS individuals with ADHD symptoms may not require specialized CBT interventions.

Cognitive and Neural Mechanisms of Behavior Therapy for Tics: A Perception-Action Integration Approach

European clinical guidelines recommend the use of Exposure and Response Prevention (ERP) and Comprehensive Behavioral Intervention for Tics (CBIT) as first-line treatments for tic disorders. Although ongoing efforts in research are being made to understand the mechanisms underlying these behavioral approaches, as of yet, the neurophysiological mechanisms behind behavioral interventions are poorly understood. However, this is essential to tailor interventions to individual patients in order to increase compliance and efficacy. The Theory of Event Coding (TEC) and its derivative BRAC (Binding and Retrieval in Action Control) provide a theoretical framework to investigate cognitive and neural processes in the context of tic disorders. In this context, tics are conceptualized as a phenomenon of enhanced perception-action binding, with premonitory urges constituting the perceptual and the motor or vocal expression constituting the action part of an event file. Based on this, CBIT is assumed to strongly affect stimulus-response binding in the context of response selection, whereas the effects of ERP presumably unfold during stimulus-response binding in the response inhibition context. Further studies are needed to clarify the neurophysiological processes underlying behavioral interventions to enable the individualization and further development of therapeutic approaches for tic disorders.

Compromised reactive but intact proactive inhibitory motor control in Tourette disorder

Tourette disorder (TD) is characterized by tics, which are sudden repetitive involuntary movements or vocalizations. Deficits in inhibitory control in TD patients remain inconclusive from the traditional method of estimating the ability to stop an impending action, which requires careful interpretation of a metric derived from race model. One possible explanation for these inconsistencies is that race model's assumptions of independent and stochastic rise of GO and STOP process to a fixed threshold are often violated, making the classical metric to assess inhibitory control less robust. Here, we used a pair of metrics derived from a recent alternative model to address why stopping performance in TD is unaffected despite atypical neural circuitry. These new metrics distinguish between proactive and reactive inhibitory control and estimate them separately. When these metrics in adult TD group were contrasted with healthy controls (HC), we identified robust deficits in reactive control, but not in proactive control in TD. The TD group exhibited difficulty in slowing down the speed of movement preparation, which they rectified by their intact ability to postpone the movement.

Test-Retest Reliability of Event-Related Potentials Across Three Tasks

Abstract. Event-related potentials (ERPs) constitute a useful and cost-effective method to assess the neural underpinnings of multiple cognitive processes. ERPs have been used to track changes in cognitive processes in longitudinal and clinical studies. However, few studies have assessed their test-retest reliability (i.e., their consistency across time). Therefore, in the current study, we aimed to assess the test-retest reliability of ERPs (P100, N100, P200, N200, P3b, lateralized readiness potentials) across three tasks. In two assessments separated by approximately 4 months, ERPs were recorded in 26 healthy participants, during two oddball tasks (motor and counting) and a stimulus-response compatibility paradigm. Pearson’s correlations and intraclass correlations were used to assess the test-retest reliability of ERPs. Correlations between ERPs elicited by the three tasks were assessed with Pearson’s correlations. Our analyses revealed moderate to very strong test-retest reliability for most ERP components across the three tasks. Test-retest reliability did not differ between the motor and counting oddball tasks. Most ERPs were also correlated across paradigms. Therefore, these results confirm that ERPs have the potential to be reliable markers to serve as robust assessment tools in longitudinal or clinical studies.

A Review of Cognitive and Behavioral Interventions for Tic Disorder

OBJECTIVES

Tic disorder is a neurodevelopmental disorder characterized by multiple involuntary movements of muscles or vocalization. Although tic symptoms subside as the patient ages, some patients suffer from significant functional impairments related to severe tic symptoms. This manuscript aimed to review the latest scientific evidences for the effect of cognitive-behavioral interventions on tic disorder.

METHODS

The relevant studies were identified by searching medical research databases. We focused our search on studies published between 2000 and 2020 in order to reflect the latest scientific evidence. A total of 821 articles were identified in the initial database search and 27 articles were finally included for the review after the exclusion of duplicated and irrelevant articles.

RESULTS

Behavioral therapies including habit reversal training, Comprehensive Behavioral Intervention for Tics, and exposure and response prevention were the most widely studied interventions for tic disorder and are recommended as first-line treatments for tic disorders with high confidence. Cognitive psychophysiologic approaches were also reported to be effective.

CONCLUSION

Further studies are needed to support the future treatment of tics with low-cost and more widely available treatments, in order to ensure better treatment outcomes.

Tourette syndrome as a motor disorder revisited - Evidence from action coding

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Feature Binding/integration in the motor domain in Tourette Syndrome (TS) is examined.

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Motor binding processes and interleaved action are intact in TS.

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Binding processes are differentially modulated in the motor domain and sensori-motor processes.

Because tics are the defining clinical feature of Tourette syndrome, it is conceptualized predominantly as a motor disorder. There is some evidence though suggesting that the neural basis of Tourette syndrome is related to perception–action processing and binding between perception and action. However, binding processes have not been examined in the motor domain in these patients. If it is particularly perception–action binding but not binding processes within the motor system, this would further corroborate that Tourette syndrome it is not predominantly, or solely, a motor disorder.

Here, we studied N = 22 Tourette patients and N = 24 healthy controls using an established action coding paradigm derived from the Theory of Event Coding framework and concomitant EEG-recording addressing binding between a planned but postponed, and an interleaved immediate reaction with different levels of overlap of action elements. Behavioral performance during interleaved action coding was normal in Tourette syndrome. Response locked lateralized readiness potentials reflecting processes related to motor execution were larger in Tourette syndrome, but only in simple conditions. However, pre-motor processes including response preparation and configuration reflected by stimulus-locked lateralized readiness potentials were normal. This was supported by a Bayesian data analysis providing evidence for the null hypothesis. The finding that processes integrating different action-related elements prior to motor execution are normal in Tourette syndrome suggests that Tourette it is not solely a motor disorder. Considering other recent evidence, the data show that changes in “binding” in Tourette syndrome are specific for perception–action integration but not for action coding.

Electrophysiology Echoes Brain Dynamics in Children and Adolescents With Tourette Syndrome-A Developmental Perspective

The development of the complex clinical picture of motor and vocal tics in children and adolescents with Tourette syndrome (TS) must be paralleled by changes in the underlying pathophysiology. Electrophysiological methods such as EEG and event-related potentials (ERPs) are non-invasive, safe and easy to apply and thus seem to provide an adequate means to investigate brain dynamics during this brain maturational period. Also, electrophysiology is characterized by a high time resolution and can reflect motor, sensory and cognitive aspects as well as sleep behavior. Hence, this narrative review focuses on how electrophysiology echoes brain dynamics during development of youngsters with TS and might be useful for the treatment of tics. A comprehensive picture of developmental brain dynamics could be revealed showing that electrophysiological parameters evolve concurrently with clinical characteristics of TS. Specifically, evidence for a maturational delay of motor inhibition related to cortico-spinal hyper-excitability and brain mechanisms for its cognitive compensation could be shown. Moreover, deviant sleep parameters and probably a stronger perception-action binding were reported. For neuromodulatory treatments (e.g., neurofeedback; repetitive transcranial magnetic stimulation, rTMS/transcranial direct current stimulation, tDCS) targeting neuronal deficits and/or strengthening compensatory brain mechanisms, pilot studies support the possibility of positive effects regarding tic reduction. Finally, attention-deficit/hyperactivity disorder (ADHD), as a highly frequent co-existing disorder with TS, has to be considered when using and interpreting electrophysiological measures in TS. In conclusion, application of electrophysiology seems to be promising regarding clinical and research aspects in youngsters with TS.

Lateralized readiness potentials and sensorimotor activity in adults with obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) patients are known to have various functional abnormalities in prefrontal and motor areas. Given the presence of compulsions in many OCD patients, impaired response preparation processes could be a core feature of OCD. Yet, these processes remain understudied from a neurophysiological standpoint. Nineteen OCD patients were matched on age and sex to 19 healthy controls. Continuous EEG was recorded in all participants during a stimulus-response compatibility task. EEG from electrodes C3 and C4 was then averaged into stimulus- and response-locked LRPs. We compared both groups on various LRP measures, such as the LRP onset, the Gratton dip, and the maximum LRP peak. OCD patients showed significantly larger LRP peak than healthy controls, as well as larger Gratton dip. However, there was no group difference regarding LRP onset. Among OCD patients, it seems that motor regions are overactive during response preparation. Such overactivity was found for both incorrect responses that are aborted before execution and responses that are truly executed. These results suggest that regulation of sensorimotor activity should be addressed in the treatment of OCD.

[Tourette syndrome: Research challenges to improve clinical practice]

Tourette syndrome is a neurodevelopmental disorder which is characterized by the presence of motor and phonic tics. These tics are generally more prevalent in childhood. Tics typically reach their maximum severity before puberty, around age 10 to 12. In most patients, tic severity usually decreases during late adolescence and adulthood. However, this is not true for all individuals. To date, the developmental trajectory leading to the persistence of tics into adulthood is still poorly understood. There are very few markers that can predict the evolution of tic symptoms from childhood to adulthood. Yet, while we cannot cure Tourette syndrome, it is possible to reduce tic severity with various treatments. The most common treatments are pharmacotherapy and behavioral and cognitive-behavioral therapy. However, there appears to be a limit to the proportion of tics that can be treated, since most treatments offer an average reduction in tics of no more than 50%. Thus, at first, this article reviews recent advances in treatment and symptom progression. Next, we propose some lines of research to improve the management and treatment of people with Tourette syndrome.

Tourette syndrome research highlights from 2018

This is the fifth yearly article in the Tourette Syndrome Research Highlights series, summarizing research from 2018 relevant to Tourette syndrome and other tic disorders. The authors briefly summarize reports they consider most important or interesting. The  highlights from 2019 article is being drafted on the Authorea online authoring platform, and readers are encouraged to add references or give feedback on our selections using the comments feature on that page. After the calendar year ends, the article is submitted as the annual update for the  Tics collection on F1000Research.