Table 3.
Clusters of significant age of onset × marijuana use interactions. GWR, gray/white matter border ratio; LGI, local gyrification index.
| Measure | Label@Max, Extended coverage | Side | Max-log(p) | VtxMax | Size (mm2) | x | y | z | Correlate | P (corr) | F-value | Effect Size** |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Thickness | Lingual | R | −2.488 | 127,927 | 1110 | 19 | −69 | −7 | MJ Years | 0.016 | 10.07 | 0.063 |
| GWR | Rostral middle frontal, | L | −2.668 | 42,505 | 1730 | −23 | 53 | 10 | MJ Grams | 0.001 | 11.09 | 1.969 |
| Rostral middle frontal | R | −3.565 | 94,896 | 2661 | 39 | 30 | 18 | MJ Years | 0.0002 | 16.6 | 0.744 | |
| Medial orbitofrontal | R | −3.304 | 84,773 | 1368 | 6 | 47 | −20 | MJ Years | 0.013 | 14.92 | 0.796 | |
| LGI | Inferior parietal | L | 3.456 | 122,169 | 2565 | −44 | −62 | 44 | MJ Grams | 0.015 | 15.89 | 0.131 |
p(corr), family-wise error fully corrected.
**
The effect sizes were derived from Freesurfer's tool in the significant region of interest using mri_segstats. This was also confirmed manually by using the F-value reported by Freesurfer.