Structural neuroimaging studies in chronic cannabis users.

Note: Yr.  =  Years; CU  =  Cannabis users; HC  =  Healthy controls; M  =  Male; F  =  Female; SD  =  Standard deviation; GM  =  Grey matter; GMd  =  Grey matter density; WM  =  White matter; WMd  =  White matter density; CSF  =  Cerebral spinal fluid; TIV  =  Total intracranial volume; FL  =  Frontal lobe; PL  =  Parietal lobe; TL  =  Temporal lobe; OL  =  Occipital lobe; BG  =  Basal ganglia; Cb  =  Cerebellum; L  =  Left hemisphere; R  =  Right hemisphere; T  =  Tesla; MRI  =  Magnetic resonance imaging; DTI  =  Diffusion tensor imaging; ROI  =  Region of interest; NE  =  Not specified; MD  =  Mean diffusivity; FA  =  Fractional anisotropy; PFC  =  Prefrontal cortex; BIS  =  Barrat Impulsivity scale.
*If not otherwise specified, results are presented in terms of chronic cannabis users.
•  =  Significant differences; ○  =  Non-significant differences;  =  Not examined.
**Two subjects in the marijuana group met criteria for excessive alcohol consumption.
***Five subjects in the marijuana group met criteria for alcohol abuse.
†Subjects with symptoms of alcohol abuse or dependence were included.
†Multiple comparison correction.