Faculty Collaboration Database

Extracting kinetic information from human motor cortical signals. Neuroimage 2014 Nov 01;101:695-703

Date

08/06/2014

Pubmed ID

25094020

DOI

10.1016/j.neuroimage.2014.07.049

Scopus ID

2-s2.0-84907029183 (requires institutional sign-in at Scopus site)   61 Citations

Abstract

Brain machine interfaces (BMIs) have the potential to provide intuitive control of neuroprostheses to restore grasp to patients with paralyzed or amputated upper limbs. For these neuroprostheses to function, the ability to accurately control grasp force is critical. Grasp force can be decoded from neuronal spikes in monkeys, and hand kinematics can be decoded using electrocorticogram (ECoG) signals recorded from the surface of the human motor cortex. We hypothesized that kinetic information about grasping could also be extracted from ECoG, and sought to decode continuously-graded grasp force. In this study, we decoded isometric pinch force with high accuracy from ECoG in 10 human subjects. The predicted signals explained from 22% to 88% (60 ± 6%, mean ± SE) of the variance in the actual force generated. We also decoded muscle activity in the finger flexors, with similar accuracy to force decoding. We found that high gamma band and time domain features of the ECoG signal were most informative about kinetics, similar to our previous findings with intracortical LFPs. In addition, we found that peak cortical representations of force applied by the index and little fingers were separated by only about 4mm. Thus, ECoG can be used to decode not only kinematics, but also kinetics of movement. This is an important step toward restoring intuitively-controlled grasp to impaired patients.

Author List

Flint RD, Wang PT, Wright ZA, King CE, Krucoff MO, Schuele SU, Rosenow JM, Hsu FP, Liu CY, Lin JJ, Sazgar M, Millett DE, Shaw SJ, Nenadic Z, Do AH, Slutzky MW

Author

Max O. Krucoff MD Assistant Professor in the Neurosurgery department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Adult
Brain Mapping
Electrodes, Implanted
Electroencephalography
Electromyography
Female
Gamma Rhythm
Hand
Humans
Isometric Contraction
Kinetics
Male
Middle Aged
Motor Cortex
Muscle, Skeletal
Young Adult