title: Reconstruction of movement-related intracortical activity from micro-electrocorticogram array signals in monkey primary motor cortex.
abstract: Subdural electrode arrays provide stable, less invasive electrocorticogram (ECoG) recordings of neural signals than multichannel needle electrodes. Accurate reconstruction of intracortical local field potentials (LFPs) from ECoG signals would provide a critical step for the development of a less invasive, high-performance brain-machine interface; however, neural signals from individual ECoG channels are generally coarse and have limitations in estimating deep layer LFPs. Here, we developed a high-density, 32-channel, micro-ECoG array and applied a sparse linear regression algorithm to reconstruct the LFPs at various depths of primary motor cortex (M1) in a monkey performing a reach-and-grasp task. At 0.2 mm beneath the cortical surface, the real and estimated LFPs were significantly correlated (correlation coefficient (r); 0.66 ± 0.11), and the r at 3.2 mm was still as high as 0.55 ± 0.04. A time-frequency analysis of the reconstructed LFP showed clear transition between resting and movements by the monkey. These methods would be a powerful tool with wide-ranging applicability in neuroscience studies.
authors.affiliation: Division of Behavioral Development, Department of Developmental Physiology, National Institute for Physiological Sciences, Aichi, Japan. watanabe@nips.ac.jp
authors.forename: Hidenori
authors.initials: H
authors.lastname: Watanabe
authors.forename: Masa-Aki
authors.initials: MA
authors.lastname: Sato
authors.forename: Takafumi
authors.initials: T
authors.lastname: Suzuki
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nambu
authors.forename: Yukio
authors.initials: Y
authors.lastname: Nishimura
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Kawato
authors.forename: Tadashi
authors.initials: T
authors.lastname: Isa
mesh_terms: D000465:Algorithms; D000818:Animals; D003627:Data Interpretation, Statistical; D004567:Electrodes, Implanted; D004569:Electroencephalography / Q000379:methods*; D006225:Hand / Q000502:physiology; D018737:Hand Strength / Q000502:physiology; D016014:Linear Models; D008251:Macaca; D008297:Male; D009044:Motor Cortex / Q000502:physiology*; D009068:Movement / Q000502:physiology*; D011597:Psychomotor Performance; D014584:User-Computer Interface