Fig. 2.

Layout of the measurement locations. The upper graph shows the 19 electrode positions. 15 of these were used in the further analysis. Fp2 and F10 were used for vEOG and hEOG. ROIs, comprising 2 electrodes were defined for the lateral electrodes. The lower graph shows the layout of the fNIRS probe array. Light-emitter and −detector positions and the resulting sampling volumes are illustrated only on the left hemisphere. From the overall 16 sampling volumes four ROIs were defined on each hemisphere (frontal, fronto-temporal, temporal and temporo-parietal) including averages across 2 NIRS channels. The image on the right shows the co-registration in a 6-month-old participant (parental permission obtained).