Concurrent Contribution of Co-Contraction to Error Reduction During Dynamic Adaptation of the Wrist

MRI-compatible robots provide a means of studying brain function involved in complex sensorimotor learning processes, such as adaptation. To properly interpret the neural correlates of behavior measured using MRI-compatible robots, it is critical to validate the measurements of motor performance obt...

Full description

Bibliographic Details
Main Authors: Andria J Farrens, Kristin Schmidt, Hannah Cohen, Fabrizio Sergi
Format: Article
Language:English
Published: IEEE 2023-01-01
Series:IEEE Transactions on Neural Systems and Rehabilitation Engineering
Subjects:
Online Access:https://ieeexplore.ieee.org/document/10042983/
_version_ 1797805117299228672
author Andria J Farrens
Kristin Schmidt
Hannah Cohen
Fabrizio Sergi
author_facet Andria J Farrens
Kristin Schmidt
Hannah Cohen
Fabrizio Sergi
author_sort Andria J Farrens
collection DOAJ
description MRI-compatible robots provide a means of studying brain function involved in complex sensorimotor learning processes, such as adaptation. To properly interpret the neural correlates of behavior measured using MRI-compatible robots, it is critical to validate the measurements of motor performance obtained via such devices. Previously, we characterized adaptation of the wrist in response to a force field applied via an MRI-compatible robot, the MR-SoftWrist. Compared to arm reaching tasks, we observed lower end magnitude of adaptation, and reductions in trajectory errors beyond those explained by adaptation. Thus, we formed two hypotheses: that the observed differences were due to measurement errors of the MR-SoftWrist; or that impedance control plays a significant role in control of wrist movements during dynamic perturbations. To test both hypotheses, we performed a two-session counterbalanced crossover study. In both sessions, participants performed wrist pointing in three force field conditions (zero force, constant, random). Participants used either the MR-SoftWrist or the UDiffWrist, a non-MRI-compatible wrist robot, for task execution in session one, and the other device in session two. To measure anticipatory co-contraction associated with impedance control, we collected surface EMG of four forearm muscles. We found no significant effect of device on behavior, validating the measurements of adaptation obtained with the MR-SoftWrist. EMG measures of co-contraction explained a significant portion of the variance in excess error reduction not attributable to adaptation. These results support the hypothesis that for the wrist, impedance control significantly contributes to reductions in trajectory errors in excess of those explained by adaptation.
first_indexed 2024-03-13T05:46:35Z
format Article
id doaj.art-d4b7676385ea4158816ddb6a2eb894e0
institution Directory Open Access Journal
issn 1558-0210
language English
last_indexed 2024-03-13T05:46:35Z
publishDate 2023-01-01
publisher IEEE
record_format Article
series IEEE Transactions on Neural Systems and Rehabilitation Engineering
spelling doaj.art-d4b7676385ea4158816ddb6a2eb894e02023-06-13T20:09:22ZengIEEEIEEE Transactions on Neural Systems and Rehabilitation Engineering1558-02102023-01-01311287129610.1109/TNSRE.2023.324260110042983Concurrent Contribution of Co-Contraction to Error Reduction During Dynamic Adaptation of the WristAndria J Farrens0https://orcid.org/0000-0003-4513-4750Kristin Schmidt1Hannah Cohen2Fabrizio Sergi3https://orcid.org/0000-0003-3019-2958Department of Mechanical and Aerospace Engineering, University of California, Irvine, Irvine, CA, USAMechanical Engineering Department, University of Delaware, Newark, DE, USABiomedical Engineering Department, University of Delaware, Newark, DE, USABiomedical Engineering Department, University of Delaware, Newark, DE, USAMRI-compatible robots provide a means of studying brain function involved in complex sensorimotor learning processes, such as adaptation. To properly interpret the neural correlates of behavior measured using MRI-compatible robots, it is critical to validate the measurements of motor performance obtained via such devices. Previously, we characterized adaptation of the wrist in response to a force field applied via an MRI-compatible robot, the MR-SoftWrist. Compared to arm reaching tasks, we observed lower end magnitude of adaptation, and reductions in trajectory errors beyond those explained by adaptation. Thus, we formed two hypotheses: that the observed differences were due to measurement errors of the MR-SoftWrist; or that impedance control plays a significant role in control of wrist movements during dynamic perturbations. To test both hypotheses, we performed a two-session counterbalanced crossover study. In both sessions, participants performed wrist pointing in three force field conditions (zero force, constant, random). Participants used either the MR-SoftWrist or the UDiffWrist, a non-MRI-compatible wrist robot, for task execution in session one, and the other device in session two. To measure anticipatory co-contraction associated with impedance control, we collected surface EMG of four forearm muscles. We found no significant effect of device on behavior, validating the measurements of adaptation obtained with the MR-SoftWrist. EMG measures of co-contraction explained a significant portion of the variance in excess error reduction not attributable to adaptation. These results support the hypothesis that for the wrist, impedance control significantly contributes to reductions in trajectory errors in excess of those explained by adaptation.https://ieeexplore.ieee.org/document/10042983/Motor adaptationEMGrobotics
spellingShingle Andria J Farrens
Kristin Schmidt
Hannah Cohen
Fabrizio Sergi
Concurrent Contribution of Co-Contraction to Error Reduction During Dynamic Adaptation of the Wrist
IEEE Transactions on Neural Systems and Rehabilitation Engineering
Motor adaptation
EMG
robotics
title Concurrent Contribution of Co-Contraction to Error Reduction During Dynamic Adaptation of the Wrist
title_full Concurrent Contribution of Co-Contraction to Error Reduction During Dynamic Adaptation of the Wrist
title_fullStr Concurrent Contribution of Co-Contraction to Error Reduction During Dynamic Adaptation of the Wrist
title_full_unstemmed Concurrent Contribution of Co-Contraction to Error Reduction During Dynamic Adaptation of the Wrist
title_short Concurrent Contribution of Co-Contraction to Error Reduction During Dynamic Adaptation of the Wrist
title_sort concurrent contribution of co contraction to error reduction during dynamic adaptation of the wrist
topic Motor adaptation
EMG
robotics
url https://ieeexplore.ieee.org/document/10042983/
work_keys_str_mv AT andriajfarrens concurrentcontributionofcocontractiontoerrorreductionduringdynamicadaptationofthewrist
AT kristinschmidt concurrentcontributionofcocontractiontoerrorreductionduringdynamicadaptationofthewrist
AT hannahcohen concurrentcontributionofcocontractiontoerrorreductionduringdynamicadaptationofthewrist
AT fabriziosergi concurrentcontributionofcocontractiontoerrorreductionduringdynamicadaptationofthewrist