Introduction: Functional cortical mapping in children is necessary for various neurosurgical procedures. Yet many of the current gold standard techniques, including fMRI, direct cortical stimulation, and Wada testing are impractical in the very young patients or ones with developmental delay, who lack the capacity to cooperate with these procedures. Passive functional cortical mapping in these patients is thus an important unmet need. Our goal is to develop an inexpensive, convenient, high-resolution EEG scalp recording system and algorithms for the same. In this study, we tested the feasibility of using conventional scalp EEG along with novel tripolar electrodes for noninvasive functional mapping and localization of motor regions in healthy adult volunteers during a hand contraction task.

Methods: Scalp EEG was recorded from both hemispheres with electrodes centered over the motor cortex area while the participants performed a repeated one-hand opening and closing task (0.5 Hz for 100 times). Data were analyzed to assess whether changes in local EEG spectral power adequately identified active motor cortex.

Results: Lateralizing changes in EEG frequency spectra were identified in electrodes over the motor cortex contralateral to the active hand. We also found high frequency EEG signatures that were available by tripolar EEG recordings, but not evident by conventional disc electrodes.

Conclusion: Scalp-EEG coupled with advanced data processing algorithms can be used to record functional signatures from activated cortex. This high resolution noninvasive functional cortical mapping technology can thus be potentially suitable for children and other vulnerable patient population, who cannot tolerate other functional mapping procedures.