Lynn E. DeLisi et al., “A preliminary DTI study showing no brain structural change associated with adolescent cannabis use,” Harm Reduction Journal 3 (May 9, 2006).

The question of whether marijuana causes brain damage, especially among adolescents, remains controversial even though most recent evidence indicates no correlation. In this study, researchers used state-of-the-art electronic imaging techniques to look for signs of brain atrophy, comparing individuals in their early 20s who had used marijuana extensively in their teens with comparable individuals who had not used marijuana. There was no sign of brain atrophy in the marijuana users.

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