Table 2. Brain regions in which activity was significantly correlated with the overall uncertainty (fourth GLM), shown for the placebo condition and for pairwise comparison with L-dopa.
| Region | MNI coordinates | peak | cluster | ||
|---|---|---|---|---|---|
| x | y | z | z-value | extent (k) | |
| Placebo | |||||
| L posterior insula | −34 | −20 | 8 | 4.63 | 198 |
| R supplementary motor cortex | 8 | 10 | 52 | 3.98 | 92 |
| R/L dorsal anterior cingulate cortex, L supplementary motor cortex |
-3 | 21 | 39 | 3.96 | 176 |
| R anterior insula | 42 | 15 | -6 | 3.46 | 38 |
| R thalamus | 8 | −10 | 2 | 3.41 | 18 |
| Placebo > L-dopa | |||||
| L posterior insula | −34 | −20 | 8 | 5.05* | 82 |
| L anterior insula, L frontal operculum | −38 | 6 | 14 | 4.88 | 222 |
| L opercular part of the inferior frontal gyrus | −42 | 9 | 26 | 4.01 | 80 |
| L precentral gyrus | −54 | 3 | 12 | 3.47 | 23 |
| R dorsal anterior cingulate cortex | 4 | 14 | 28 | 3.41 | 32 |
| R precentral gyrus | 39 | -9 | 44 | 3.39 | 16 |
| L dorsal anterior cingulate cortex | -2 | 36 | 33 | 3.32 | 17 |
| L-dopa > placebo | |||||
| no suprathreshold activation | |||||
Note: Thresholded at p<0.001, uncorrected, with k ≥ 10 voxels; L: left; R: right.
*p=0.031, FWE-corrected for whole-brain volume.