Human neocortical electrical activity recorded on nonpenetrating microwire arrays: applicability for neuroprostheses

Neurosurg Focus. 2009 Jul;27(1):E9. doi: 10.3171/2009.4.FOCUS0974.


Object: The goal of this study was to determine whether a nonpenetrating, high-density microwire array could provide sufficient information to serve as the interface for decoding motor cortical signals.

Methods: Arrays of nonpenetrating microwires were implanted over the human motor cortex in 2 patients. The patients performed directed stereotypical reaching movements in 2 directions. The resulting data were used to determine whether the reach direction could be distinguished through a frequency power analysis.

Results: Correlation analysis revealed decreasing signal correlation with distance. The gamma-band power during motor planning allowed binary classification of gross directionality in the reaching movements. The degree of power change was correlated to the underlying gyral pattern.

Conclusions: The nonpenetrating microwire platform showed good potential for allowing differentiated signals to be recorded with high spatial fidelity without cortical penetration.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Action Potentials
  • Arm / physiology
  • Electrodes, Implanted
  • Electroencephalography / methods*
  • Electrophysiology
  • Epilepsy / diagnosis
  • Epilepsy / physiopathology
  • Fingers / physiology
  • Humans
  • Male
  • Microelectrodes*
  • Motor Activity / physiology
  • Motor Cortex / physiology*
  • Movement / physiology*
  • Neocortex / physiology
  • Prostheses and Implants*
  • Task Performance and Analysis
  • User-Computer Interface*