neuroscientist carl hart. >> there are not many people studying marijuana.ry difficult to get approved to study marijuana. >> what's nice about israel is that the government is helping the research to happen. >> and it's research that could give hope to patients like charlotte figge. scientists in israel are learning that marijuana use might actually protect the brain, not damage it. >> they've been able to show that it can decrease the amount of brain damage from head injuries in mice. >> right. to be able to give a medicine after the injury to reverse some of the damage, that's huge. >> i want to paint my nails. >> you want the paint your nails? i'll paint your nails. >> i literally see charlotte's brain making connections that haven't been made in years. it's almost seeming to build her brain where before it seemed broken. >> and while scientists are still at the early stages of knowing if this is actually happening, i can tell you it was remarkable to see her progress. in the three months since we first met her, we saw a change. she was now talking more.