Table 6.

Overview of radial diffusivity differences in cannabis users compared to controls, and their association with cannabis exposure levels and other variables.

References	Cannabis users vs. controls	Correlations
Cousijn et al. (2022)	n.s.	n.s. onset age, duration, grams/past 2 wks and dependence severity
Lichenstein et al. (2022)	n.s. anterior thalamic radiations, cingulum	-
Sweigert et al. (2020)	↓ Middle cerebellar peduncle	Neg. cor craving scores (MCQ-SF) and middle cerebellar peduncle n.s. CUDIT-R total score
Levar et al. (2018)	n.s. uncinate fasciculus	-
Jakabek et al. (2016)	n.s.	Neg. cor. duration and angular bundle n.s. frequency of current use
Orr et al. (2016)	n.s.	Neg. cor. onset age and SLF, inferior longitudinal fasciculus, lateral prefrontal cortex, corpus callosum (anterior/posterior)
Rigucci et al. (2016)	trend ↑ corpus callosum	Corpus callosum daily/high potency users > low potency users > never used/used weekly
Becker et al. (2015)	trend ↓ corpus callosum (genu)	-
Filbey et al. (2014)	↓ forceps minor	Quadratic assoc. duration and forceps minor (larger with initial regular use and lower with continued use)
Zalesky et al. (2012)	n.s.	Pos. cor. onset age and commissural fibres, fimbria
Ashtari et al. (2009)	↑ middle temporal gyrus tracts, superior temporal gyrus, internal capsule, thalamic radiation [voxel wise analysis of covariance] ↑ arcuate fasciculus [tractography]	n.s. onset age, duration, dosage, abstinence length

Cor, correlated; n.s., non-significant; neg, negative; pos, positive; SLF, superior longitudinal fasciculus; wks, weeks; ↓, Cannabis Users < Controls; ↑ Cannabis Users > Controls.