Research Progress on Control Mechanism and Application of UCM Synergies Theory

Motor synergies is the core issue in the field of motor control, and the concept of uncontrolled manifold(UCM) has greatly promoted the cognition of motor synergies. This study reviewed the origin, basic concept and analysis process of UCM synergies, and compared with other synergy theories. The following issues were discussed in this study: 1) Neural control structure and control model of UCM synergies. The evidences show that the neural control sites of UCM synergies is not the cerebral cortex,but the subcortical structure. Its control model includes feedback control model, referent configuration model and feedforward control model. UCM synergies in behavioral level is the result of neural control, external force, interaction torque between joints and torque generated by multi joint muscles coupling different joints. 2) Application of UCM synergies in the fields of skill learning,diagnosis and rehabilitation of neurological diseases, healthy aging, motor development of children, and motor(vocational) skill control. The quantitative indicators of UCM synergies can effectively distinguish the stage differences in the learning process of motor skills, as well as the group differences between neuropathy patients and normal people, different ages and different skill levels. Future researches should focus on: 1) Investigate the non-destructive technologies to interfere the deep brain regions directly.2) The intersegmental dynamics can be used to verify whether the interaction torque between segments and coupling of multi joint muscles to different joints is the main source of UCM synergies from the perspective of biomechanics. 3) More researches are needed to explore the motor control mechanism of high-level athletes from the perspective of UCM synergies. 4) Explore methods to improve the synergy ability of specific skills in sports.