Cortical activity during motor execution, motor imagery, and imagery-based online feedback
See allHide authors and affiliations
Edited* by Riitta Hari, Helsinki University of Technology, Espoo, Finland, and approved January 14, 2010 (received for review November 26, 2009)

Abstract
Imagery of motor movement plays an important role in learning of complex motor skills, from learning to serve in tennis to perfecting a pirouette in ballet. What and where are the neural substrates that underlie motor imagery-based learning? We measured electrocorticographic cortical surface potentials in eight human subjects during overt action and kinesthetic imagery of the same movement, focusing on power in “high frequency” (76–100 Hz) and “low frequency” (8–32 Hz) ranges. We quantitatively establish that the spatial distribution of local neuronal population activity during motor imagery mimics the spatial distribution of activity during actual motor movement. By comparing responses to electrocortical stimulation with imagery-induced cortical surface activity, we demonstrate the role of primary motor areas in movement imagery. The magnitude of imagery-induced cortical activity change was ∼25% of that associated with actual movement. However, when subjects learned to use this imagery to control a computer cursor in a simple feedback task, the imagery-induced activity change was significantly augmented, even exceeding that of overt movement.
Footnotes
- 1To whom correspondence may be addressed. E-mail: kjmiller{at}u.washington.edu or rao{at}cs.washington.edu.
Author contributions: K.J.M., G.S., E.E.F., M.d.N., J.O., and R.P.N.R. designed research; K.J.M. and J.G.O. performed research; K.J.M. and G.S. contributed new reagents/analytic tools; K.J.M. and G.S. analyzed data; and K.J.M., G.S., E.E.F., J.G.O., and R.P.N.R. wrote the paper.
The authors declare no conflict of interest.
↵*This Direct Submission article had a prearranged editor.
This article contains supporting information online at www.pnas.org/cgi/content/full/0913697107/DCSupplemental.
Citation Manager Formats
Article Classifications
- Biological Sciences
- Neuroscience