What strategies does the nervous system use to optimally control the muscles?
It is easy to think of the output of the motor system as being movement -- and this is certainly true. Yet the most immediate product of the motor system is the activity of 'motor units'. A motor unit is a single spinal motoneuron and the muscle fibers it innervates. The fundamental goal of the motor system is both blindingly simple and bafflingly complex: activate motor units so as to maximize the reward to the organism.
We thus seek to understand the empirical patterns of motor unit activity and how they relate to normative predictions regarding how motor units should be activated. This involves recording and identifying the activity of single motor units in EMG recordings. We do so using a novel isometric task in which we can command arbitrary pattern of muscle force.
Single motor units are sorted using the Binary Pursuit algorithm developed by Jonathan Pillow and colleagues.