Table 8.
Local maxima for LV 10: easy versus hard retrieval events, group interaction
| Temporal lag | Bootstrap ratio | Spatial extent | Talairach coordinates |
HEM | Gyral location | Brodmann area | Significant post hoc ANOVA results | ||
|---|---|---|---|---|---|---|---|---|---|
| x | y | z | |||||||
| Young easy > hard, MA hard > easy | |||||||||
| Left hemisphere | |||||||||
| 3 | 4.33 | 23 | −23 | 24 | 10 | Left | Claustrum | ||
| 3 | 4.28 | 16 | −20 | 4 | 66 | Left | Superior frontal gyrus | 6 | |
| 2 | 3.99 | 15 | −34 | 24 | 10 | Left | Insula | 13 | |
| 2 | 3.96 | 42 | −35 | −83 | −8 | Left | Middle occipital gyrus | 18*# | R: group × difficulty and task × difficulty |
| 2 | 3.90 | 21 | −12 | −17 | 6 | Left | Thalamus | ||
| 3 | 3.72 | 12 | −45 | −56 | −16 | Left | Fusiform gyrus | 37* | R: group × difficulty |
| Right hemisphere | |||||||||
| 3, 4 | 4.99 | 21 | 47 | −18 | −22 | Right | Inferior temporal gyrus | 20* | R: group × difficulty |
| 2, 3 | 4.99 | 253 | 36 | −79 | −13 | Right | Middle occipital/fusiform gyrus | 18/19* | R: group × difficulty and task × difficulty |
| 2–4 | 4.84 | 33 | 18 | 40 | −2 | Right | Middle and medial frontal gyrus | 10*# | R: group × difficulty |
| 2 | 3.94 | 61 | 6 | −13 | 3 | Right | Thalamus | ||
| 3 | 3.89 | 10 | 10 | −2 | 4 | Right | Lentiform nucleus | ||
| 3 | 3.86 | 10 | 66 | −43 | −2 | Right | Middle temporal gyrus | 21* | R: group × difficulty |
| 3 | 3.84 | 11 | 36 | 37 | −6 | Right | Inferior frontal gyrus | 47* | R: group × difficulty |
Note: Temporal lag represents the time after event onset, when a cluster of voxels exhibited a contrast effect of interest. The bootstrap ratio threshold was set to ±>3.28, and identified dominant and stable activation clusters. The spatial extent refers to the total number of voxels included in the voxel cluster (threshold = 10).The stereotaxic coordinates are measured in millimeters, and gyral location and Brodmann areas (BAs) were determined by referring to Talairach and Tournoux (1988). The last column presents the highest order significant effect (P < 0.05) observed from the ROI-based post hoc group × task × difficulty repeated-measures ANOVAs. R, significant effects for retrieval activity; HEM, cerebral hemisphere in which the activation occurred. Regions marked with # were ROIs for which: 1) mean activity was extracted and plotted in a bar graph and 2) were ROIS included in the brain–behavior regression analyses.