RECENT STUDIES AND RESEARCH CONDUCTD BY INVESTGATORS AT THE CHILDRENS HOSPITAL OF PHILADELPHIA IN US (LED BY MANZAR ASHTARI)HAVE STATED THAT CANNABIS AFFECTS AREAS OF THE BRAIN INVOLVED IN HE ORGANS DEVELOPMENT AND CAN HAVE SERIOUS REPERCUSSIONS ON MEMORY,ATTENTION,DECISION-MAKING,LANGUAGE AND EXEUTIVE FUNCTIONING CENTERS......studies of normal brain development reveal critical areas of the brain that develop during late adolesence,and our study shows that heavy cannabis use is associated with damage in those brain regions ,ashtari also said.THE abnormal pattens of water diffusion that we found among the young men with histories of marijuana use suggest damage or an arrest in development of the myelin sheath that surrounds brain-cells.he noted from studies that the results suggested that early-onset substance use may alter the development of white mattercircuits,especially those connections among the frontal,parietal and temporal regions of the brain .abnormal whie matter development could slow information transfer in the brain and affect cognitive functions.HE CONCLUDED THAT,FURTHER RESEARCH SHOULD BE DONE TO INVESTIGATE THE RELATION BETWEEN REPEATED MARIJUANA USE AND WHITE MATTER DEVELOPMENT.HOWEVER,OUR WORK REINFORCES THE IDEA THAT THE ADOLECENT BRAIN AY BE ESPECIALLY VULNERABLE TO RISKY BEHAVIORS SUCH AS SUBSTANCE ABUSE,BECAUSE OF CRUCIAL NEURAL DEVELOPMENT THAT ACCURS DURING THOSE YEARS......just because theres alot young guns on here......u no who u are...lolpeace