Coupling effect between lateralized alpha power and original HbO. The T-map shows positive coupling for the T-only cueing trials (A) and negative coupling for D-only cueing trials (B) within subjects. The statistical parameters are thresholded at P < 0.05. The bottom bar graphs (C) illustrate positive coupling in the left T-ROI for T-only cueing trials and a significantly inverse coupling in the right D-ROI for D-only cueing trials. (^*P < 0.05). Correlation between the coupling effects and RT for the T-only cueing trials (D) and D-only cueing trials (E). Note that the cue could point to either the right or left visual field.