Background: Cannabis has been associated vvith transient psychotic states; howevcr, the causal relationship between cannabis and schizophrenia continues to remain a maller of debate. Epidemiological and some biological studies hint at cannabis being an indcpendent risk factor for schizophrenia; this has not been definitively proved.                                
Aims: We aimed to understand the patterns of glucose uptake in important brain regions among individuals with cannabis dependence and schizophrenia. Furthermore. we compared the interregiOlialmetabolic rates in pel1inent neural circuits among individuals with cannabis dependence, schizophrenia and normal controls.                                                        
Setting and Design: This is a case-control cross-sectional study that was carried out by a general psychiatry department in collaboration with a nuclear diagnosis unit.                                                                                                                  
Materials and Methods: Male volunteers with cannabis dependence. schizophrenia and normal controls underwent FOG PET scanning. Glucose uptakes in pre-selected regions of interest were compared using MANOVA. Finally, Chow tests were used to compare interregionall11etabolic relationships in the mesocortical and cortical-subcortical-cerebellum eircuits.       
Results: Significant differences (P<0.05)wcre noted among individuals with cannabis dependence and schizophrenia in the medial and lateral temporal regions. When the neural circuits were compared. significant interregional diJTerences (P<0.05) were noted between individuals with cannabis dependence and normal controls. However. among individuals with cannabis dependence and schiwphrenia, no significant diffcrences (P>0.05) were noted inthese patterns. 
Conclusions: Our findings suggest that cannabis dependence can alter interregional relationships in a manner similar t.o schizophrenia. This.indicates that cannabis could potentially playa role in the development of psychosis by altering neural circuits.