title: Analysis of the synergies underlying complex hand manipulation.
abstract: Coupling of actuators into motor synergies has been observed repeatedly, and is traditionally interpreted as a strategy for simplifying complex coordination problems. This view implies a small number of task-independent synergies. We have shown that optimal feedback control also gives rise to synergies in the absence of any simplification; the structure and number of such optimal synergies depends on the task. To compare these hypotheses, we recorded hand postures from a range of complex manipulation task. The structure of the synergies we extracted (via PCA) was task-dependent, and their number significantly exceeded previous observations in a simpler grasping task. Our results lend support to an optimal control explanation rather than a "simplicity" explanation.
authors.affiliation: Department of Cognitive Science, University of California at San Diego, CA, USA.
authors.forename: E
authors.initials: E
authors.lastname: Todorov
authors.forename: Z
authors.initials: Z
authors.lastname: Ghahramani