Extraction and localization of mesoscopic motor control signals for human ECoG neuroprosthetics

J Neurosci Methods. 2008 Jan 15;167(1):63-81. doi: 10.1016/j.jneumeth.2007.04.019. Epub 2007 May 5.

Abstract

Electrocorticogram (ECoG) recordings for neuroprosthetics provide a mesoscopic level of abstraction of brain function between microwire single neuron recordings and the electroencephalogram (EEG). Single-trial ECoG neural interfaces require appropriate feature extraction and signal processing methods to identify and model in real-time signatures of motor events in spontaneous brain activity. Here, we develop the clinical experimental paradigm and analysis tools to record broadband (1Hz to 6kHz) ECoG from patients participating in a reaching and pointing task. Motivated by the significant role of amplitude modulated rate coding in extracellular spike based brain-machine interfaces (BMIs), we develop methods to quantify spatio-temporal intermittent increased ECoG voltages to determine if they provide viable control inputs for ECoG neural interfaces. This study seeks to explore preprocessing modalities that emphasize amplitude modulation across frequencies and channels in the ECoG above the level of noisy background fluctuations in order to derive the commands for complex, continuous control tasks. Preliminary experiments show that it is possible to derive online predictive models and spatially localize the generation of commands in the cortex for motor tasks using amplitude modulated ECoG.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Biofeedback, Psychology
  • Brain Mapping*
  • Cerebral Cortex / physiopathology*
  • Electroencephalography*
  • Epilepsies, Partial / pathology
  • Epilepsies, Partial / physiopathology
  • Epilepsies, Partial / rehabilitation
  • Female
  • Hand / physiopathology
  • Humans
  • Magnetic Resonance Imaging
  • Physical Therapy Modalities
  • Psychomotor Performance / physiology*
  • Signal Processing, Computer-Assisted*
  • Spectrum Analysis
  • User-Computer Interface*