Table 1.
Locations with a significant correlation between working memory task-related BOLD activity at that location and volume of the indicated structure (“main effect” model, controlling for group and gender)
| Structural volume used as independent variable | Location (mm) of significant correlation between structural volume and WM BOLD activitya | Volume of cluster (mm3) | P value of cluster extentb | t statistic at peak within clusterc | |
|---|---|---|---|---|---|
| 1 | SFG | −40, −41, 40 (IPS, L) | 486 | 0.038 | −4.26 |
| 2 | SFG | 35, −46, 40 (IPS, R) | 432 | 0.047 | −3.93 |
| 3 | MFG | −38, −50, 43 (IPS, L) | 864 | 0.013 | −4.48 |
| 4 | Hippocampus | −56, 12, 1 (IFG, L) | 945 | 0.009 | 4.19 |
| 5 | Hippocampus | 1, 16, 43 (dACC) | 2403 | 0.001 | 5.33 |
df = 145 for SFG and MFG as the structural variable, and 143 for hippocampus
IPS intraparietal sulcus, IFG inferior frontal gyrus, dACC dorsal anterior cingulate cortex, L left, R right
Coordinates are the center of the cluster after conversion to MNI152 space
P values for cluster extent were computed using permutation testing and one-tailed tests. The search volume for clusters was restricted to a set of regions independently identified in previous studies as regions involved in working memory task performance (Fig. 1)
Sign indicates the direction of the relationship (i.e., negative values indicate an inverse correlation)