Classification of contralateral and ipsilateral finger movements for electrocorticographic brain-computer interfaces

Neurosurg Focus. 2009 Jul;27(1):E12. doi: 10.3171/2009.4.FOCUS0981.


Electrocorticography (ECoG) offers a powerful and versatile platform for developing brain-computer interfaces; it avoids the risks of brain-invasive methods such as intracortical implants while providing significantly higher signal-to-noise ratio than noninvasive techniques such as electroencephalography. The authors demonstrate that both contra- and ipsilateral finger movements can be discriminated from ECoG signals recorded from a single brain hemisphere. The ECoG activation patterns over sensorimotor areas for contra- and ipsilateral movements were found to overlap to a large degree in the recorded hemisphere. Ipsilateral movements, however, produced less pronounced activity compared with contralateral movements. The authors also found that single-trial classification of movements could be improved by selecting patient-specific frequency components in high-frequency bands (> 50 Hz). Their discovery that ipsilateral hand movements can be discriminated from ECoG signals from a single hemisphere has important implications for neurorehabilitation, suggesting in particular the possibility of regaining ipsilateral movement control using signals from an intact hemisphere after damage to the other hemisphere.

Publication types

  • Case Reports
  • Comparative Study

MeSH terms

  • Adult
  • Brain Mapping / methods
  • Cerebral Cortex / physiology*
  • Electrodes, Implanted
  • Electroencephalography / methods
  • Electroencephalography / statistics & numerical data*
  • Electromyography
  • Epilepsy / diagnosis
  • Epilepsy / rehabilitation
  • Evoked Potentials, Motor / physiology
  • Fingers / physiology*
  • Functional Laterality / physiology*
  • Humans
  • Male
  • Motor Cortex / physiology
  • Movement / physiology*
  • Prostheses and Implants
  • Prosthesis Design / methods
  • Reaction Time / physiology
  • Somatosensory Cortex / physiology
  • Subdural Space / physiology
  • User-Computer Interface*