Table 4.
Regions significantly active in the INTERNAL vs EXTERNAL contrast (P <0.001, volume-corrected)
| Control | Autism | Interaction | ||||
|---|---|---|---|---|---|---|
| Region | (X, Y, Z) | t-value | (X, Y, Z) | t-value | (X, Y, Z) | t-value |
| Internal > External | ||||||
| L inferior frontal gyrus | (−38, 28, 0) | 7.97 | – | – | – | – |
| Mid-cingulate | (2, −16, 32) | 7.54 | – | – | – | – |
| Dorsal MPFC | (−1, 51, 24) | 7.00 | – | – | * | * |
| Dorsal anterior cingulate | (−2, 20, 20) | 5.59 | – | – | – | – |
| External > Internal | ||||||
| Retrosplenial cortex | (−5, −48, 8) | 11.31 | (11, −49, 4) | 11.66 | – | – |
| L superior frontal gyrus | (−21, 20, 48) | 8.47 | (−21, 23, 47) | 9.18 | – | – |
| Posterior cingulate | (3, −33, 39) | 8.36 | (−1, −40, 27) | 5.43 | – | – |
| L parahippocampal gyrus | (−18, −33, −12) | 7.96 | (−25, −25, −9) | 9.18 | – | – |
| L middle temporal gyrus | (−38, −73, 29) | 6.25 | (−30, −73, 20) | 10.12 | (−38, −77, 23) | 4.53 |
| R superior frontal gyrus | (38, 20, 52) | 5.85 | (23, 23, 47) | 8.01 | (18, 16, 52) | 5.28 |
| R middle temporal gyrus | (47, −68, 24) | 5.40 | (42, −76, 35) | 5.94 | – | – |
| Midbrain | – | – | (−1, −20, −9) | 5.70 | (−1, −21, −9) | 5.43 |
| R thalamus | – | – | (23, −24, 16) | 5.39 | (22, −13, 8) | 4.58 |
| R cuneus | – | – | (14, −77, 11) | 9.26 | – | – |
| R parahippocampal gyrus | – | – | (26, −29, −5) | 8.13 | – | – |
| L cuneus | – | – | (−5, −77, 7) | 6.28 | – | – |
*A dMPFC cluster [Talairach location = (2, 40, 12); t-value = 5.12; volume = 300 mm3] just missed the cluster volume threshold of 384 mm3. Talairach coordinates and t-values correspond to the most significant voxel within each cluster. Group by condition interactions (P <0.001, volume-corrected) are listed for all regions that exhibited significant effects of condition in either the autism or control group. For all regions with significant interactions, the autism group had a greater difference in activity between EXTERNAL and INTERNAL conditions than the control group.