Figure 4. Pearson correlation coefficient (r) values between both two-back and three-back performance and normalized power in each region and band.

The normalized difference between eyes closed and open power (zECO) revealed negative associations with two-back performance and left temporal and occipital power. Three-back performance was found to be inversely associated with delta/theta eyes open power in both the left and right occipital regions (1–7 Hz, R/L occipital). Eyes closed bilateral frontal and left temporal alpha and beta power were mildly positively associated with three-back working memory performance. The delta/theta band power in the bilateral occipital, bilateral parietal, right posterior frontal, and right temporal regions was most associated with three-back WM performance. The zECO power revealed negative associations with three-back performance in several delta/theta regions and significant correlations in the right posterior frontal and right parietal regions. * = Bonferroni corrected p<0.05.