Table 1.
Group differences in SM-related activity on Placebo. Regions showing a main effect of age group are shown (contiguous clusters of ≥5 voxels at P < 0.001, uncorrected)
| Location (x, y, z) | Peak Z (n) | Region | Brodmann area | R > F significant in young group | R < F significant in old group |
| −15, 6, 24 | 4.16 (18) | Left body of caudate | — | P < 0.001 | (P < 0.005) |
| 18, 27, 0 | 3.50 (11) | Right head of caudate | — | P < 0.001 | (P < 0.005) |
| −33, 6, 27 | 3.38 (7) | Left precentral gyrus | BA 6 | P < 0.001 | — |
| −30, −42, −6 | 3.33 (6) | Left posterior parahippocampal gyrus/hippocampus | BA 19/37/— | (P < 0.005) | P < 0.001 |
| −39, 21, 24 | 3.25 (6) | Left middle frontal gyrus | BA 46 | P < 0.001 | — |
| −36, 33, −12 | 3.12 (6) | Left inferior frontal gyrus | BA 47 | (P < 0.005) | — |
Note: N refers to the number of significant voxels in each cluster; Z refers the Z statistic value for each peak or subpeak; and x, y, and z refer to distances in millimeter from the origin in MNI space (see Materials and Methods). Follow-up tests assessed SM (R > F) and subsequent forgetting (R < F) effects in the 2 groups; only those that yielded significant results are shown. For these, findings from comparisons using more lenient thresholds are also shown in brackets to indicate trends. **Indicates reliable at P < 0.001; *indicates reliable at P < 0.005