The teenager's brain has a lot of developing to do: It must transform from the brain of a child into the brain of an adult. Some researchers worry how marijuana might affect that crucial process.
"Actually, in childhood our brain is larger," says Krista Lisdahl, director of the brain imaging and neuropsychology lab at University of Wisconsin, Milwaukee. "Then, during the teenage years, our brain is getting rid of those connections that weren't really used, and it prunes back.
The big winner was 12 Years a Slave, but there was quite a bit of love to go around at Sunday night's Oscars. What there wasn't, as usual, was a lot of riveting television.
Sure, there was John Travolta squinting at the teleprompter and introducing Idina Menzel (to sing the Oscar-winning Best Original Song "Let It Go," from Frozen) as — no kidding — "Adele Dazeem." And there was a fun dance number featuring Pharrell Williams and his own Oscar-nominated "Happy," which he wore a formal black version of his Grammys hat to perform.
About a year ago, pediatric otolaryngologist Blake Papsin went into a patient's room at The Hospital for Sick Children in Toronto. He was surprised by the roar of a sleep machine the parents had brought to help their child conk out amid the beeps and buzzes of the hospital.
Now to Venezuela where violent clashes continue between antigovernment protesters and national guard security forces who are using water cannons and tear gas to break up demonstrations. On Friday, dozens of people, including journalists, were arrested. And on Saturday, more protests erupted around the city. So far, 18 people have died.
Joining us now in Caracas is reporter Girish Gupta who has been covering the unrest. Girish, tell us what things are like there today.
It's ALL THINGS CONSIDERED from NPR West. I'm Arun Rath.
Events in Ukraine have taken another dramatic turn. Russian forces now control Ukraine's Crimean peninsula. The Ukrainian government in Kiev is calling up its military reserves. Secretary of State John Kerry says Russia's military incursion is an incredible act of aggression. Kerry will meet with the new Ukrainian government in Kiev on Tuesday.