title: Local spatial correlation analysis of hand flexion/extension using intraoperative high-density ECoG.
abstract: We recorded motor cortical activity using highdensity electrocorticogram (ECoG) from three patients during awake craniotomy. Subjects repeatedly executed hand flexion/extension tasks according to auditory instructions. Clear event-related desynchronization (ERD) in beta band (8-32) Hz and event-related synchronization (ERS) in gamma band (60-200) Hz were observed. High frequency band (HFB: 60-200 Hz) activation was found to be more localized compared to low frequency band (LFB: 8-32 Hz) activation in all subjects. Local spatial correlation maps in LFB and HFB were constructed by computing the correlation between channels. Local spatial correlation dropped more in the ERD/ERS areas consistently in two subjects. The results indicate that ERD/ERS patterns are more spatially uncorrelated and denser ECoG electrode is necessary within these areas to map uncorrelated `sources'. High resolution electrodes might improve both clinical functional mapping and brain machine interface outcomes in the near future.
authors.forename: Tianxiao
authors.initials: T
authors.lastname: Jiang
authors.forename: Nuri F
authors.initials: NF
authors.lastname: Ince
authors.forename: Tao
authors.initials: T
authors.lastname: Jiang
authors.forename: Taylor
authors.initials: T
authors.lastname: Wang
authors.forename: Shenshen
authors.initials: S
authors.lastname: Mei
authors.forename: Yunlin
authors.initials: Y
authors.lastname: Li
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Wang
authors.forename: Zhiyi
authors.initials: Z
authors.lastname: Sha
mesh_terms: D000328:Adult; D001921:Brain; D001931:Brain Mapping / Q000379:methods*; D062207:Brain-Computer Interfaces; D000069280:Electrocorticography; D004566:Electrodes; D004569:Electroencephalography / Q000379:methods*; D005071:Evoked Potentials; D005260:Female; D006225:Hand / Q000502:physiology*; D006801:Humans; D008297:Male; D009044:Motor Cortex / Q000502:physiology; D009068:Movement / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted