title: Correspondence of electroencephalography and near-infrared spectroscopy sensitivities to the cerebral cortex using a high-density layout.
abstract: This study investigates the correspondence of the cortical sensitivity of electroencephalography (EEG) and near-infrared spectroscopy (NIRS). EEG forward model sensitivity to the cerebral cortex was calculated for 329 EEG electrodes following the 10-5 EEG positioning system using a segmented structural magnetic resonance imaging scan of a human subject. NIRS forward model sensitivity was calculated for the same subject using 156 NIRS source-detector pairs selected from 32 source and 32 detector optodes positioned on the scalp using a subset of the 10-5 EEG positioning system. Sensitivity correlations between colocalized NIRS source-detector pair groups and EEG channels yieldedR= 0.46 ± 0.08. Groups of NIRS source-detector pairs with maximum correlations to EEG electrode sensitivities are tabulated. The mean correlation between the point spread functions for EEG and NIRS regions of interest (ROI) wasR= 0.43 ± 0.07. Spherical ROIs with radii of 26 mm yielded the maximum correlation between EEG and NIRS averaged across all cortical mesh nodes. These sensitivity correlations between EEG and NIRS should be taken into account when designing multimodal studies of neurovascular coupling and when using NIRS as a statistical prior for EEG source localization.
authors.affiliation: Thayer School of Engineering at Dartmouth, 14 Engineering Drive, Hanover, New Hampshire 03755, United States.
authors.forename: Paolo
authors.initials: P
authors.lastname: Giacometti
authors.affiliation: Thayer School of Engineering at Dartmouth, 14 Engineering Drive, Hanover, New Hampshire 03755, United States.
authors.forename: Solomon G
authors.initials: SG
authors.lastname: Diamond
keywords: diffuse optical tomography; electroencephalography; forward model; inverse model; near-infrared spectroscopy; sensitivity