A model-based approach to predict muscle synergies using optimization: application to feedback control

This paper presents a new model-based method to define muscle synergies. Unlike the conventional factorization approach, which extracts synergies from electromyographic data, the proposed method employs a biomechanical model and formally defines the synergies as the solution of an optimal control problem. As a result, the number of required synergies is directly related to the dimensions of the operational space. The estimated synergies are posture-dependent, which correlate well with the results of standard factorization methods. Two examples are used to showcase this method: a two-dimensional forearm model, and a three-dimensional driver arm model. It has been shown here that the synergies need to be task-specific (i.e., they are defined for the specific operational spaces: the elbow angle and the steering wheel angle in the two systems). This functional definition of synergies results in a low-dimensional control space, in which every force in the operational space is accurately created by a unique combination of synergies. As such, there is no need for extra criteria (e.g., minimizing effort) in the process of motion control. This approach is motivated by the need for fast and bio-plausible feedback control of musculoskeletal systems, and can have important implications in engineering, motor control, and biomechanics.

[1]  Michael I. Jordan,et al.  Optimal feedback control as a theory of motor coordination , 2002, Nature Neuroscience.

[2]  W. Rymer,et al.  Endpoint force fluctuations reveal flexible rather than synergistic patterns of muscle cooperation. , 2008, Journal of neurophysiology.

[3]  Oussama Khatib,et al.  A unified approach for motion and force control of robot manipulators: The operational space formulation , 1987, IEEE J. Robotics Autom..

[4]  Emanuel Todorov,et al.  Structured variability of muscle activations supports the minimal intervention principle of motor control. , 2009, Journal of neurophysiology.

[5]  E. Bizzi,et al.  Article history: , 2005 .

[6]  Richard R Neptune,et al.  Modular control of human walking: a simulation study. , 2009, Journal of biomechanics.

[7]  Lena H Ting,et al.  Dimensional reduction in sensorimotor systems: a framework for understanding muscle coordination of posture. , 2007, Progress in brain research.

[8]  Aymar de Rugy,et al.  Muscle Coordination Is Habitual Rather than Optimal , 2012, The Journal of Neuroscience.

[9]  G. Loeb,et al.  Spinal-Like Regulator Facilitates Control of a Two-Degree-of-Freedom Wrist , 2010, The Journal of Neuroscience.

[10]  Auke Jan Ijspeert,et al.  Central pattern generators for locomotion control in animals and robots: A review , 2008, Neural Networks.

[11]  Hana Čechová,et al.  Three-body segment musculoskeletal model of the upper limb , 2013 .

[12]  Aymar de Rugy,et al.  Generalization of visuomotor adaptation to different muscles is less efficient: experiment and model. , 2010, Human movement science.

[13]  Naser Mehrabi,et al.  A Physics-Based Musculoskeletal Driver Model to Study Steering Tasks , 2015 .

[14]  Matthew C. Tresch,et al.  The number and choice of muscles impact the results of muscle synergy analyses , 2013, Front. Comput. Neurosci..

[15]  Seyed A Safavynia,et al.  Muscle Synergies: Implications for Clinical Evaluation and Rehabilitation of Movement. , 2011, Topics in spinal cord injury rehabilitation.

[16]  Emanuel Todorov,et al.  From task parameters to motor synergies: A hierarchical framework for approximately optimal control of redundant manipulators , 2005 .

[17]  Dario Farina,et al.  A musculoskeletal model of human locomotion driven by a low dimensional set of impulsive excitation primitives , 2013, Front. Comput. Neurosci..

[18]  H. Sebastian Seung,et al.  Algorithms for Non-negative Matrix Factorization , 2000, NIPS.

[19]  M G Pandy,et al.  Musculoskeletal Model of the Upper Limb Based on the Visible Human Male Dataset , 2001, Computer methods in biomechanics and biomedical engineering.

[20]  Ryouhei Hayama,et al.  Preliminary Research on Muscle Activity in Driver’s Steering Maneuver for Driver’s Assistance System Evaluation , 2013 .

[21]  Gregor Schöner,et al.  The uncontrolled manifold concept: identifying control variables for a functional task , 1999, Experimental Brain Research.

[22]  Andrea d'Avella,et al.  Modularity in the motor system: decomposition of muscle patterns as combinations of time-varying synergies , 2001, NIPS.

[23]  Francesco Lacquaniti,et al.  Modulation of phasic and tonic muscle synergies with reaching direction and speed. , 2008, Journal of neurophysiology.

[24]  K Aminian,et al.  How well do the muscular synergies extracted via non-negative matrix factorisation explain the variation of torque at shoulder joint? , 2013, Computer methods in biomechanics and biomedical engineering.

[25]  Aymar de Rugy,et al.  Are muscle synergies useful for neural control? , 2013, Front. Comput. Neurosci..

[26]  Gerald E. Loeb,et al.  Optimal isn’t good enough , 2012, Biological Cybernetics.

[27]  Walter Herzog,et al.  Model-based estimation of muscle forces exerted during movements. , 2007, Clinical biomechanics.

[28]  S Jonsson,et al.  Function of the muscles of the upper limb in car driving. V: The supraspinatus, infraspinatus, teres minor and teres major muscles. , 1976, Ergonomics.

[29]  Francisco J. Valero Cuevas,et al.  Challenges and New Approaches to Proving the Existence of Muscle Synergies of Neural Origin , 2012, PLoS Comput. Biol..

[30]  Andrea d'Avella,et al.  Effective force control by muscle synergies , 2014, Front. Comput. Neurosci..

[31]  Donald E. Kirk,et al.  Optimal control theory : an introduction , 1970 .

[32]  John McPhee,et al.  Optimal Control and Forward Dynamics of Human Periodic Motions Using Fourier Series for Muscle Excitation Patterns , 2014 .

[33]  D. B. Lockhart,et al.  Optimal sensorimotor transformations for balance , 2007, Nature Neuroscience.

[34]  L. Ting,et al.  Functional muscle synergies constrain force production during postural tasks. , 2008, Journal of biomechanics.

[35]  Naser Mehrabi,et al.  A Neuronal Model of Central Pattern Generator to Account for Natural Motion Variation , 2016 .

[36]  M G Pandy,et al.  Static and dynamic optimization solutions for gait are practically equivalent. , 2001, Journal of biomechanics.

[37]  P. Morasso Spatial control of arm movements , 2004, Experimental Brain Research.

[38]  John McPhee,et al.  Steering disturbance rejection using a physics-based neuromusculoskeletal driver model , 2015 .

[39]  Stefano Panzeri,et al.  A unifying model of concurrent spatial and temporal modularity in muscle activity. , 2014, Journal of neurophysiology.

[40]  M. Tresch,et al.  The case for and against muscle synergies , 2022 .

[41]  Aymar de Rugy,et al.  Generalization of visuomotor adaptation to different muscles is less efficient: Experiment and model , 2010 .

[42]  Richard R Neptune,et al.  Three-dimensional modular control of human walking. , 2012, Journal of biomechanics.

[43]  B Jonsson,et al.  Function of the muscles of the upper limb in car driving. IV: the pectoralis major, serratus anterior and latissimus dorsi muscles. , 1975, Ergonomics.

[44]  Francesco Lacquaniti,et al.  Can modular strategies simplify neural control of multidirectional human locomotion? , 2014, Journal of neurophysiology.

[45]  E. Bizzi,et al.  Modules in the brain stem and spinal cord underlying motor behaviors. , 2011, Journal of neurophysiology.

[46]  D. Thelen Adjustment of muscle mechanics model parameters to simulate dynamic contractions in older adults. , 2003, Journal of biomechanical engineering.

[47]  Emanuel Todorov,et al.  From task parameters to motor synergies: A hierarchical framework for approximately optimal control of redundant manipulators , 2005, J. Field Robotics.

[48]  D. Hoffman,et al.  Muscle and movement representations in the primary motor cortex. , 1999, Science.

[49]  Anthony Jarc,et al.  Simplified and effective motor control based on muscle synergies to exploit musculoskeletal dynamics , 2009, Proceedings of the National Academy of Sciences.

[50]  Arun Ramakrishnan,et al.  A simple experimentally based model using proprioceptive regulation of motor primitives captures adjusted trajectory formation in spinal frogs. , 2010, Journal of neurophysiology.

[51]  Francesco Lacquaniti,et al.  Motor Control Programs and Walking , 2006, The Neuroscientist : a review journal bringing neurobiology, neurology and psychiatry.