Table 3.
Summary of differences in white matter integrity per diffusion-MRI metric in cannabis users compared to controls.
| White matter tract | FA | MD | RD | AD | FBL | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| ↓ | ↑ | ↓ | ↑ | ↓ | ↑ | ↓ | ↑ | ↑ | ||
| Superior longitudinal fasciculus | 7 | - | - | 1 | - | - | - | - | - | - |
| Corpus callosum | 5 | 1 | - | 4 | 1 | 1 | - | - | - | - |
| Anterior thalamic radiation | 2 | 1 | - | 1 | 1 | 1 | - | - | - | - |
| Internal capsule | 3 | 1 | - | 1 | - | 1 | - | - | - | - |
| Uncinate fasciculus | 3 | - | 1 | - | 1 | - | - | - | - | 1 |
| Inferior frontal-occipital fasciculus | 3 | - | - | - | 1 | - | - | - | - | - |
| Forceps major | 1 | - | - | - | - | - | - | - | - | - |
| External capsule | 1 | - | - | - | - | - | - | - | - | - |
| Corona radiata | 3 | - | - | - | - | - | - | - | - | - |
| Posterior thalamic radiation | 1 | - | - | - | - | - | - | - | - | - |
| Forceps minor | 1 | 1 | - | 1 | 1 | - | - | - | - | - |
| Frontal region* | 2 | - | - | - | - | - | - | - | - | - |
| Temporal gyrus* | 3 | - | - | 1 | - | 2 | - | - | - | - |
| Adjacent to the hippocampus | 1 | - | - | - | - | - | - | - | - | - |
| Arcuate fasciculus | 1 | - | - | - | - | 1 | - | - | - | - |
| Crus cerebri* | 1 | - | - | - | - | - | - | - | - | - |
| Temporo-thalamic* | 1 | - | - | - | - | - | - | - | - | - |
| Occipito-frontal* | 1 | - | - | - | - | - | - | - | - | - |
| Middle cerebellar peduncle | 1 | 1 | 1 | - | 1 | - | - | - | - | - |
| Occipito cuneus* | - | 1 | - | - | - | - | - | - | - | - |
| Inferior longitudinal fasciculus | - | - | 1 | - | - | - | - | - | - | - |
| Middle frontal gyrus* | - | - | 1 | - | - | - | - | - | - | - |
| Posterior cingulate* | - | - | 1 | - | - | - | - | - | - | - |
| Occipito-lingual gyrus* | - | 1 | - | - | - | - | - | - | - | - |
| Anterior cingulate cortex* | - | - | - | 1 | - | - | - | - | - | - |
| Motor tracts* | - | - | - | - | - | - | 1 | - | - | - |
-, no findings;
*
listed gray matter region in results; suggests white matter tracts within region, FA, fractional anisotropy; MD, mean diffusivity; RD, radial diffusivity; AD, axial diffusivity; FBL, fibre bundle length; ↓, Cannabis users < Controls; ↑, Cannabis users > Controls. In addition, the network related metrics (e.g., small worldness) are not represented in this table as they relate to the network as a whole and not white matter tracts.