Fig. 9.

Temporal correlation between frontal EEG asymmetry and BOLD activity of the left amygdala during the rtfMRI-nf training. A) Average values of the psychophysiological interaction (PPI) analysis coefficients — interaction (‘Inter’) and correlation (‘Corr’) — for the left amygdala (LA) ROI (Fig. 2A) for the experimental group (EG). Frontal EEG asymmetry (FEA) for channels F3 and F4 (denoted as ‘F4 − F3’) was used in the PPI analysis. The voxel-wise [FEA-based regressor] × [Happy − Count] interaction and correlation values were averaged within the LA ROI and across the group. The error bars are standard errors of the means (sem). The positive PPI interaction indicates a stronger temporal correlation between the FEA and the LA BOLD activity during the Happy Memories condition. B) Corresponding PPI results for the control group (CG). C) Illustration of the PPI effects for the EG using single-subject data. The left plot shows positive correlation between the FEA-based regressor and the LA time course during four Happy Memories (H) condition blocks in one run (Fig. 1B) concatenated together in the figure. The right plot shows lack of correlation between these time courses during four concatenated Count (C) condition blocks in the same run.