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In order to probe the production of kinematic cues to signal boundaries in action sequences, adults performed sequences of three actions on an object, with or without an action boundary following the second action. Movement of the hand was recorded via motion tracking, and it was found that the boundary was marked by a lengthening of the pre-boundary action and by a pause. These cues are also found in prosody to signal phrase boundaries in speech, suggesting a close coupling of the mechanisms underlying boundary production in both domains.

Background: The occurrence of tics is the main basis for the diagnosis of Gilles de la Tourette syndrome (GTS). Video‐based tic assessments are time consuming. Objective: The aim was to assess the potential of automated video‐based tic detection for discriminating between videos of adults with GTS and healthy control (HC) participants. Methods: The quantity and temporal structure of automatically detected tics/extra movements in videos from adults with GTS (107 videos from 42 participants) and matched HCs were used to classify videos using cross‐validated logistic regression. Results: Videos were classified with high accuracy both from the quantity of tics (balanced accuracy of 87.9%) and the number of tic clusters (90.2%). Logistic regression prediction probability provides a graded measure of diagnostic confidence. Expert review of about 25% of lower‐confidence predictions could ensure an overall classification accuracy above 95%. Conclusions: Automated video‐based methods have a great potential to support quantitative assessment and clinical decision‐making in tic disorders. [ABSTRACT FROM AUTHOR]

Background: Although functional neurological movement disorders (FMD) are characterized by motor symptoms, sensory processing has also been shown to be disturbed. However, how the integration of perception and motor processes, essential for the control of goal‐directed behavior, is altered in patients with FMD is less clear. A detailed investigation of these processes is crucial to foster a better understanding of the pathophysiology of FMD and can systematically be achieved in the framework of the theory of event coding (TEC). Objective: The aim was to investigate perception–action integration processes on a behavioral and neurophysiological level in patients with FMD. Methods: A total of 21 patients and 21 controls were investigated with a TEC‐related task, including concomitant electroencephalogram (EEG) recording. We focused on EEG correlates established to reflect perception–action integration processes. Temporal decomposition allowed to distinguish between EEG codes reflecting sensory (S‐cluster), motor (R‐cluster), and integrated sensory–motor processing (C‐cluster). We also applied source localization analyses. Results: Behaviorally, patients revealed stronger binding between perception and action, as evidenced by difficulties in reconfiguring previously established stimulus–response associations. Such hyperbinding was paralleled by a modulation of neuronal activity clusters, including reduced C‐cluster modulations of the inferior parietal cortex and altered R‐cluster modulations in the inferior frontal gyrus. Correlations of these modulations with symptom severity were also evident. Conclusions: Our study shows that FMD is characterized by altered integration of sensory information with motor processes. Relations between clinical severity and both behavioral performance and neurophysiological abnormalities indicate that perception–action integration processes are central and a promising concept for the understanding of FMD. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Background: Currently, there is a marked increase of young people with sudden onset of tic‐like behaviors (TLBs) resembling movements and vocalizations presented on social media videos as "Tourette's syndrome." Objective: To delineate clinical phenomenology of TLBs after social media exposure in comparison with clinical features of Tourette's syndrome. Methods: We compared demographic and clinical variables between 13 patients with TLBs and 13 age‐ and sex‐related patients with Tourette's syndrome. Results: Patients with TLBs had several characteristics allowing to distinguish them from patients with Tourette's syndrome, some of which discriminated perfectly (ie, abrupt symptom onset, lack of spontaneous symptom fluctuations, symptom deterioration in the presence of others) and some nearly perfectly (ie, predominantly complex movements involving trunk/extremities). Also, symptom onset was significantly later. Conclusions: TLBs after social media consumption differ from tics in Tourette's syndrome, strongly suggesting that these phenomena are categorically different conditions. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society [ABSTRACT FROM AUTHOR]

The article discusses the Modified Rush Video-Based Tic Rating Scale (MRVS) and proposes changes to improve its standardization. However, the authors of the article raise concerns about some of the proposed changes, such as the lack of an instruction to not suppress tics and the reduction of rating time, which may result in the underrepresentation of tics. They also question the validity of the comparison between tic counts from different intervals and the increase in internal consistency for the revised score. Additionally, the authors argue that a high convergent validity between the MRVS and the Yale Global Tic Severity Scale (YGTSS) is not desirable, as they assess different aspects of the condition. Overall, the authors recommend further evaluation and reconsideration of the suggested changes. [Extracted from the article]

Functional movement disorders are amongst the most common and disabling neurological conditions, placing a significant burden on the healthcare system. Despite the frequency and importance of functional movement disorders, our understanding of the underlying pathophysiology is limited, hindering the development of causal treatment options. Traditionally, functional movement disorders were considered as a psychiatric condition, associated with involuntary movements triggered by psychological stressors. Recent neurophysiological studies have unveiled cognitive alterations in affected individuals, suggesting that functional movement disorders might be better characterized by overarching neural principles governing cognitive functions. For instance, recent research has shown that the retrieval of stimulus-response bindings is altered in patients with functional movement disorders. Building upon these recent findings, our study delves into whether the initial integration of stimulus and response information is also disrupted in patients with functional movement disorders. To accomplish this, we reanalysed previously collected EEG data using refined analysis methods that provide insights into oscillatory activity and functional neuroanatomy associated with the integration of stimulus-response bindings. Our results demonstrate that post-movement beta synchronization (i) predicts behavioural stimulus-response binding and (ii) is significantly increased in patients with functional movement disorders compared to healthy controls. Utilizing beamformer analysis, we localized the difference effect to a cluster centred around the left supplementary motor area and the correlation effect to the right supplementary motor area. Extending beyond recent research that focused on the retrieval of stimulus-response bindings, our present findings reveal that the integration of stimulus and response information is already impaired in patients with functional movement disorders. These results uncover a phenomenon of hyperbinding between perception and action, which may represent a fundamental mechanism contributing to the movement impairments in patients with functional movement disorders., Competing Interests: The authors report no competing interests., (© The Author(s) 2024. Published by Oxford University Press on behalf of the Guarantors of Brain.)