Understanding how the nervous system learns to coordinate the large number of degrees of freedom in the body to produce goal-directed movement is not only one of the central questions in theoretical movement neuroscience, but also has direct relevance for movement rehabilitation. In spite of the centrality of this issue, the literature on how a new coordination pattern is acquired and refined when first learning a novel task remains surprisingly small relative to studies that focus on modifications of already well-learned coordination patterns. In this chapter, we outline some of the reasons behind why the study of coordination continues to pose a serious challenge for movement neuroscience, particularly when it comes to systematically studying and testing hypotheses on how new coordination patterns are organized and reorganized with practice. We then describe a novel experimental paradigm-the body-machine interface (BoMI)-that has been developed and used over the last decade to examine this issue. The paradigm combines the control of a large number of degrees of freedom along with a linear mapping, which makes it appealing to examine how coordination of these high degrees of freedom is organized in a systematic fashion. Finally, we outline some of the new insights that this paradigm has provided into classic issues of motor learning such as the learning of high-dimensional spaces, generalization, and transfer.
Keywords: Body–machine interface (BoMI); Glove-cursor task; Motor learning; Muscle synergies; Null space; Principal component (PC); Redundant movements; Task space.