RT Journal Article
SR Electronic
T1 Decoupling the Cortical Power Spectrum Reveals Real-Time Representation of Individual Finger Movements in Humans
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 3132
OP 3137
DO 10.1523/JNEUROSCI.5506-08.2009
VO 29
IS 10
A1 Miller, K. J.
A1 Zanos, S.
A1 Fetz, E. E.
A1 den Nijs, M.
A1 Ojemann, J. G.
YR 2009
UL http://www.jneurosci.org/content/29/10/3132.abstract
AB During active movement the electric potentials measured from the surface of the motor cortex exhibit consistent modulation, revealing two distinguishable processes in the power spectrum. At frequencies <40 Hz, narrow-band power decreases occur with movement over widely distributed cortical areas, while at higher frequencies there are spatially more focal power increases. These high-frequency changes have commonly been assumed to reflect synchronous rhythms, analogous to lower-frequency phenomena, but it has recently been proposed that they reflect a broad-band spectral change across the entire spectrum, which could be obscured by synchronous rhythms at low frequencies. In 10 human subjects performing a finger movement task, we demonstrate that a principal component type of decomposition can naively separate low-frequency narrow-band rhythms from an asynchronous, broad-spectral, change at all frequencies between 5 and 200 Hz. This broad-spectral change exhibited spatially discrete representation for individual fingers and reproduced the temporal movement trajectories of different individual fingers.