Using EEG to differentiate between higher and lower level hierarchical control nodes in human motor performance
Humans are capable of rapid, error free complex actions. For example, most people can accurately type 5-6 letters a second, yet we tend to be poor when asked to identify key locations on a keyboard. This presents an interesting paradox. It is as if whatever processes or mechanisms involved in motor planning have no idea what our effectors are doing during movement. Hierarchical control frameworks do a good job explaining normal human motor performance. For example, higher level nodes may be involved in planning and error monitoring, whereas lower level nodes may be involved in the kinematics of the response, relying on sensory and tactile feedback to guide actions. In my talk I will present recent findings from our laboratory, using EEG to measure changes in neural oscillatory frequencies over time while participants engaged in typing tasks. I will present evidence that changes in frontal-midline theta serve as a marker for the level of cognitive control exerted by higher level nodes during action. I will also discuss the implications of these findings for advancing the quality and performance of brain-machine interfaces (BMIs).