caa a22 4500 528784188 20190323032148.0 cr unu---uuuuu 180924e201506 xx s 000 0 eng 10.3929/ethz-b-000105206 doi 10.1186/s12984-015-0045-1 doi (ETHRESEARCH)oai:www.research-collection.ethz.ch:20.500.11850/105206 Increased task-uncorrelated muscle activity in childhood dystonia [Elektronische Daten] [Francesca Lunardini, Serena Maggioni, Claudia Casellato, Matteo Bertucco, Alessandra L.G. Pedrocchi, Terence D. Sanger] J Neuroeng Rehabil Open access ethresearch Background Even if movement abnormalities in dystonia are obvious on observation-based examinations, objective measures to characterize dystonia and to gain insights into its pathophysiology are still strongly needed. We hypothesize that motor abnormalities in childhood dystonia are partially due to the inability to suppress involuntary variable muscle activity irrelevant to the achievement of the desired motor task, resulting in the superposition of unwanted motion components on the desired movement. However, it is difficult to separate and quantify appropriate and inappropriate motor signals combined in the same muscle, especially during movement. Methods We devise an innovative and practical method to objectively measure movement abnormalities during the performance of a continuous figure-eight writing task in 7 children with dystonia and 9 age-matched healthy controls. During the execution of a continuous writing task, muscle contractions should occur at frequencies that match the frequencies of the writing outcome. We compare the power spectra of kinematic trajectories and electromyographic signals of 8 upper limb muscles to separate muscle activity with the same frequency content of the figure-eight movement (task-correlated) from activity occurring at frequencies extraneous to the task (task-uncorrelated). Results Children with dystonia present a greater magnitude of task-uncorrelated muscle components. The motor performance achieved by children with dystonia is characterized by an overall lower quality, with high spatial and temporal variability and an altered trade-off between speed and accuracy. Conclusions Findings are consistent with the hypothesis that, in childhood dystonia, the ability to appropriately suppress variable and uncorrelated elements of movement is impaired. Here we present a proof-of-concept of a promising tool to characterize the phenomenology of movement disorders and to inform the design of neurorehabilitation therapies. Creative Commons Attribution 4.0 International http://creativecommons.org/licenses/by/4.0 ethresearch Childhood dystonia ethresearch Writing ethresearch EMG-kinematics ethresearch Spectral analysis ethresearch Task-uncorrelated activity ethresearch Lunardini Francesca joint author Maggioni Serena joint author Casellato Claudia joint author Bertucco Matteo joint author Pedrocchi Alessandra L.G. joint author Sanger Terence D. joint author Journal of NeuroEngineering and Rehabilitation London : BioMed Central 12, p. 52 1743-0003 http://hdl.handle.net/20.500.11850/105206 text/html WWW-Backlink auf das Repository (Open access) 1 Journal Article ethresearch ETHRESEARCH 856 40 http://hdl.handle.net/20.500.11850/105206 text/html WWW-Backlink auf das Repository (Open access) ETHRESEARCH 700 1- Lunardini Francesca joint author ETHRESEARCH 700 1- Maggioni Serena joint author ETHRESEARCH 700 1- Casellato Claudia joint author ETHRESEARCH 700 1- Bertucco Matteo joint author ETHRESEARCH 700 1- Pedrocchi Alessandra L.G. joint author ETHRESEARCH 700 1- Sanger Terence D. joint author ETHRESEARCH 773 0- Journal of NeuroEngineering and Rehabilitation London : BioMed Central 12, p. 52 1743-0003 BK010053 XK010053 XK010000 ETHRESEARCH ETHRESEARCH ETHRESEARCH Journal Article Open access