Your brain on marijuana

Dr. Sanjay Gupta explains how marijuana affects the brain and how pot can be used to treat certain conditions.

01:39 - Source: CNN
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An Israeli agricultural engineer inspects marijuana plants at the BOL (Breath Of Life) Pharma greenhouse in the country's second-largest medical cannabis plantation, near Kfar Pines in northern Israel, on March 9, 2016.
The recreational use of cannabis is illegal in the Jewish state, but for the past 10 years its therapeutic use has not only been permitted but also encouraged. Last year, doctors prescribed the herb to about 25,000 patients suffering from cancer, epilepsy, post-traumatic stress and degenerative diseases. The purpose is not to cure them but to alleviate their symptoms. Forbidden to export its cannabis plants, Israel is concentrating instead on marketing its agronomic, medical and technological expertise in the hope of becoming a world hub in the field.
 / AFP / JACK GUEZ        (Photo credit should read JACK GUEZ/AFP/Getty Images)
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 GO WITH AFP STORY by Desiree Martin A picture taken on April 12, 2013 shows plants of marijuana at the plantation of the Sibaratas Med Can association in Mogan on the southwest coast of the island of Gran Canaria. The plants grow from cuttings for approximately two months and then blossom before being harvested, dried, stored in jars for a month and later processed to be consumed on site. Spanish law prohibits the possession of soft drugs like cannabis in public and its growth to be sold for profit is illegal. But the law does tolerate growing cannabis for personal use and its consumption in private. Dozens of private marijuana smoking clubs operate across Spain that take advantage of this legal loophole that serve cannabis users who do not want to get their drugs from the streets. AFP PHOTO / DESIREE MARTIN (Photo credit should read DESIREE MARTIN/AFP/Getty Images)
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