Sensorimotor Control System Limitations

FUNDAMENTAL LIMITATIONS OF THE SENSORIMOTOR CONTROL SYSTEM Is there a limit to how fast we can move? We examined the fundamental limitations of the sensorimotor control system, specifically while tracking fast movements. The ability to move fast and accurately track moving objects is constrained by the biophysics of neurons and dynamics of the muscles involved. Yet, the corresponding tradeoffs between these factors and tracking motor commands have not been rigorously quantified. We use feedback control principles to identify performance limitations of the sensorimotor control system to track fast periodic movements [1]. Moreover, given neural trajectories in the motor and premotor cortices of a nonhuman primate during complicated reach and grasp behaviors, we can learn these systems-level models accurately and efficiently [2]. This body of work has important implications in sensorimotor control. For example, if the primary motor cortex is compromised due to disease or damage, the theory suggests ways to manipulate muscle dynamics by adding the necessary compensatory forces using an assistive neuroprosthetic device to restore motor performance and, more important, fast and agile movements. Just how one should compensate can be informed by theory developed in [1].

[1] Saxena S., Sarma S.V., Dahleh M. “Performance Limitations in Sensorimotor Control: Trade-offs between Neural Computing and Accuracy in Fast Tracking.” Neural Computation, 2020.

[2] Saxena S., D’Aleo R., Schieber M., Dahleh M., Sarma S.V. “Reconstructing Neural Activity and Kinematics Using a Systems-Level Model of Sensorimotor Control” Proceedings of the IEEE Engineering in Medicine and Biology Conference, 2018.