title: A synergy-based hand control is encoded in human motor cortical areas.
abstract: How the human brain controls hand movements to carry out different tasks is still debated. The concept of synergy has been proposed to indicate functional modules that may simplify the control of hand postures by simultaneously recruiting sets of muscles and joints. However, whether and to what extent synergic hand postures are encoded as such at a cortical level remains unknown. Here, we combined kinematic, electromyography, and brain activity measures obtained by functional magnetic resonance imaging while subjects performed a variety of movements towards virtual objects. Hand postural information, encoded through kinematic synergies, were represented in cortical areas devoted to hand motor control and successfully discriminated individual grasping movements, significantly outperforming alternative somatotopic or muscle-based models. Importantly, hand postural synergies were predicted by neural activation patterns within primary motor cortex. These findings support a novel cortical organization for hand movement control and open potential applications for brain-computer interfaces and neuroprostheses.
authors.affiliation: Laboratory of Clinical Biochemistry and Molecular Biology, University of Pisa, Pisa, Italy.|Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Leo
authors.affiliation: Laboratory of Clinical Biochemistry and Molecular Biology, University of Pisa, Pisa, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Handjaras
authors.affiliation: Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.|Advanced Robotics Department, Istituto Italiano di Tecnologia, Genova, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Bianchi
authors.affiliation: Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.
authors.forename: Hamal
authors.initials: H
authors.lastname: Marino
authors.affiliation: Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.|Advanced Robotics Department, Istituto Italiano di Tecnologia, Genova, Italy.|Department of Civil and Industrial Engineering, University of Pisa, Pisa, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Gabiccini
authors.affiliation: Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Guidi
authors.affiliation: Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.|Department of Information Engineering, University of Pisa, Pisa, Italy.
authors.forename: Enzo Pasquale
authors.initials: EP
authors.lastname: Scilingo
authors.affiliation: Laboratory of Clinical Biochemistry and Molecular Biology, University of Pisa, Pisa, Italy.|Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.|Clinical Psychology Branch, Pisa University Hospital, Pisa, Italy.|IMT School for Advanced Studies Lucca, Lucca, Italy.
authors.forename: Pietro
authors.initials: P
authors.lastname: Pietrini
authors.affiliation: Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.|Advanced Robotics Department, Istituto Italiano di Tecnologia, Genova, Italy.
authors.forename: Antonio
authors.initials: A
authors.lastname: Bicchi
authors.affiliation: School of Biological and Health Systems Engineering, Arizona State University, Tempe, United States.
authors.forename: Marco
authors.initials: M
authors.lastname: Santello
authors.affiliation: Laboratory of Clinical Biochemistry and Molecular Biology, University of Pisa, Pisa, Italy.|Research Center 'E. Piaggio', University of Pisa, Pisa, Italy.
authors.forename: Emiliano
authors.initials: E
authors.lastname: Ricciardi
mesh_terms: D001696:Biomechanical Phenomena; D004576:Electromyography; D006225:Hand / Q000502:physiology*; D006801:Humans; D008124:Locomotion; D008279:Magnetic Resonance Imaging; D008959:Models, Neurological; D009044:Motor Cortex / Q000502:physiology*; D011187:Posture
keywords: decoding; encoding; fMRI; hand control; human; motor cortex; neuroscience; synergies