Tic Phenomenology and Tic Awareness in Adults With Autism

Addressing co-occurring conditions in behavioural therapy for tic disorders: a review and guideline

Co-occurring psychiatric conditions are very common in tic disorders and Tourette syndrome. These additional symptoms are often detrimental to quality of life and may impact upon the implementation and efficacy of evidence-based behavioural therapies (BT) for tics. Combining a review of the available literature, relevant theory, and expert clinical practice, we present a guideline for implementing behavioural and psychosocial interventions when common comorbidities are present. These include attention-deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), anxiety, disruptive behaviour, autism spectrum disorder (ASD) and depression. Practical recommendations are provided for assessment, formulation and management of specific and multiple comorbidities in BT for both children and adults. Despite comorbidities being common in tic disorders, few studies have comprehensively addressed how they may influence the efficacy or implementation of existing therapies or how such treatments may need to be modified or sequenced. We outline recommendations for future research, including randomised control trials of BT for those with specific or multiple comorbidities, as well as adequately powered sub-group analyses within larger scale trials or naturalistic study designs. Transdiagnostic models of psychiatric disorders and treatment, including modular cross-diagnostic therapies, which recognise the dimensionality of psychiatric disorders are also highlighted as an important focus in treatment development in tic disorders.

Co-morbid tics and stereotypies: a systematic literature review

BACKGROUND

Tics and stereotypies are childhood-onset repetitive behaviours that can pose significant diagnostic challenges in clinical practice. Both tics and stereotypies are characterised by a complex co-morbidity profile, however little is known about the co-occurrence of these hyperkinetic disorders in the same patient population.

OBJECTIVE

This review aimed to assess the relationship between tics and stereotypies when these conditions present in co-morbidity.

METHODS

We conducted a systematic literature review of original studies on co-morbid tics and stereotypies, according to the standards outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Our literature search identified six studies of suitable sample size (n ≥ 40) presenting data on the association between tics and stereotypies in otherwise typically developing patients. A considerable proportion (23%) of patients diagnosed with stereotypic movement disorder present with co-morbid tics (range 18-43%). Likewise, the prevalence of primary stereotypies is increased in patients with tic disorders such as Tourette syndrome (8%, range 6-12%).

DISCUSSION

Tics and stereotypies can often develop in co-morbidity. The association of tics and stereotypies in the same patient has practical implications, in consideration of the different treatment approaches. Future research should focus on the assessment and management of both conditions, particularly in special populations (e.g. patients with pervasive developmental disorders).

Clinical characteristics of comorbid tic disorders in autism spectrum disorder: exploratory analysis

BACKGROUND

The frequency, clinical characteristics, and associated symptoms of comorbid tic disorders in individuals with autism spectrum disorder (ASD) remain unclear.

METHODS

We included subsets of individuals from a larger genetic study who were diagnosed with ASD (n = 679; age: 4-18 years) and completed the Yale Global Tic Severity Scale (YGTSS) questionnaire. Based on the YGTSS score, the individuals were divided into two groups: ASD only (n = 554) and ASD with tics (n = 125). Individuals were assessed using the verbal and non-verbal intelligence quotient (IQ), Vineland Adaptive Behavior Scale (VABS-2), Social Responsiveness Scale-2 (SRS-2), Child Behavior Checklists (CBCL), and Yale-Brown Obsessive-Compulsive Scale (YBOCS), followed by between-group comparisons. All statistical analyses were performed using the Statistical Package for the Social Sciences (SPSS) version 26.

RESULTS

Tic symptoms were observed in 125 (18.4%) participants; among them, most participants presented both motor and vocal tics (n = 40, 40.0%). The ASD with tics group had a significantly higher average age and full-scale IQ score than the ASD only group. After adjusting for age, the ASD with tics group had significantly higher scores in the SRS-2, CBCL, and YBOCS subdomains than the ASD only group. Furthermore, all variables except the non-verbal IQ and VABS-2 scores were positively correlated with the YGTSS total score. Finally, the proportion of tic symptoms was significantly higher among individuals with a higher IQ score (≥ 70).

CONCLUSIONS

The IQ score was positively correlated with the proportion of tic symptoms among individuals with ASD. Moreover, the severity of the core and comorbid symptoms of ASD was associated with the occurrence and severity of tic disorders. Our findings suggest the need for appropriate clinical interventions for individuals with ASD. Trial registration This study retrospectively registered participants.

Extra Movements in Healthy People: Challenging the Definition and Diagnostic Practice of Tic Disorders

The occurrence of motor/vocal tics, that is, "extra movements" and/or "extra vocalizations," is the leading diagnostic criterion for tic disorders. We show that extra movements are common also in healthy controls, so that a surplus of movements per se is not indicative of the presence of a tic disorder. This questions the usefulness of Diagnostic and Statistical Manual of Mental Disorders, 5th edition criteria for tic disorders in clinical practice. Apparently, it is not solely a surplus of movements that defines tic disorders. Instead, movement characteristics and patterns seem to play a crucial role. ANN NEUROL 2023;93:472-478.

Myoclonus and other jerky movement disorders

Myoclonus and other jerky movements form a large heterogeneous group of disorders. Clinical neurophysiology studies can have an important contribution to support diagnosis but also to gain insight in the pathophysiology of different kind of jerks. This review focuses on myoclonus, tics, startle disorders, restless legs syndrome, and periodic leg movements during sleep. Myoclonus is defined as brief, shock-like movements, and subtypes can be classified based the anatomical origin. Both the clinical phenotype and the neurophysiological tests support this classification: cortical, cortical-subcortical, subcortical/non-segmental, segmental, peripheral, and functional jerks. The most important techniques used are polymyography and the combination of electromyography-electroencephalography focused on jerk-locked back-averaging, cortico-muscular coherence, and the Bereitschaftspotential. Clinically, the differential diagnosis of myoclonus includes tics, and this diagnosis is mainly based on the history with premonitory urges and the ability to suppress the tic. Electrophysiological tests are mainly applied in a research setting and include the Bereitschaftspotential, local field potentials, transcranial magnetic stimulation, and pre-pulse inhibition. Jerks due to a startling stimulus form the group of startle syndromes. This group includes disorders with an exaggerated startle reflex, such as hyperekplexia and stiff person syndrome, but also neuropsychiatric and stimulus-induced disorders. For these disorders polymyography combined with a startling stimulus can be useful to determine the pattern of muscle activation and thus the diagnosis. Assessment of symptoms in restless legs syndrome and periodic leg movements during sleep can be performed with different validated scoring criteria with the help of electromyography.

The spectrum of involuntary vocalizations in humans: A video atlas

In clinical practice, involuntary vocalizing behaviors are typically associated with Tourette syndrome and other tic disorders. However, they may also be encountered throughout the entire tenor of neuropsychiatry, movement disorders, and neurodevelopmental syndromes. Importantly, involuntary vocalizing behaviors may often constitute a predominant clinical sign, and, therefore, their early recognition and appropriate classification are necessary to guide diagnosis and treatment. Clinical literature and video-documented cases on the topic are surprisingly scarce. Here, we pooled data from 5 expert centers of movement disorders, with instructive video material to cover the entire range of involuntary vocalizations in humans. Medical literature was also reviewed to document the range of possible etiologies associated with the different types of vocalizing behaviors and to explore treatment options. We propose a phenomenological classification of involuntary vocalizations within different categorical domains, including (1) tics and tic-like vocalizations, (2) vocalizations as part of stereotypies, (3) vocalizations as part of dystonia or chorea, (4) continuous vocalizing behaviors such as groaning or grunting, (5) pathological laughter and crying, (6) vocalizations resembling physiological reflexes, and (7) other vocalizations, for example, those associated with exaggerated startle responses, as part of epilepsy and sleep-related phenomena. We provide comprehensive lists of their associated etiologies, including neurodevelopmental, neurodegenerative, neuroimmunological, and structural causes and clinical clues. We then expand on the pathophysiology of the different vocalizing behaviors and comment on available treatment options. Finally, we present an algorithmic approach that covers the wide range of involuntary vocalizations in humans, with the ultimate goal of improving diagnostic accuracy and guiding appropriate treatment. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Tics and functional tic-like movements: Can we tell them apart?

Within the broad spectrum of movement disorders, tics and functional tic-like movements belong to a particular clinical category. Both types of movements are within the range of normal movement kinematics and muscle synergies, but appear repetitive and without appropriate context embedment. Historically, there have been many attempts to separate the 2 types of movements, but because of their phenomenological overlap, clinical distinction may be prone to error, and misdiagnoses may often occur. Most importantly, the 2 types of movement may coexist. Here, we review the available literature on the 2 types of motor phenomena and demonstrate some of the difficulties in distinguishing tics from functional tic-like movements on clinical grounds. We also highlight similarities and differences in pathophysiologic characteristics, documenting the significance of action monitoring, attentional allocation, and behavioral reinforcement in both types of movements, as well as in their risk factors. We discuss the overlap of current behavioral treatments for tics and functional tic-like movements and emphasize implications of diagnostic mislabeling. Such implications include the need to tailor behavioral treatment approaches to individual phenomenological profiles and guiding decision making for severe patients requiring invasive interventions, such as deep brain stimulation. A deeper insight from clinicians with respect to persisting challenges in classifying and differentiating these motor phenomena could accelerate the development of reliable clinical and physiologic markers (i.e., next generation phenotyping) and a neurobiology-driven therapeutic approach for these motor phenomena.