>> hurd showed me under the microscope. this is a healthy brain. lots of cells, lots of connections. >> beautiful, the branching, the communication is essential for every single thing we do. >> this is a brain on drugs. specifically, opioids. >> so one of the things you can see is that there's not that many networks. >> looks like a poorly populated neighborhood. >> exactly. >> this is what a brain disease looks like. opioids have damaged these receptors, the glutamate receptors in the prefrontal cortex of the brain making it harder to make decisions, use good judgment, making it harder to just say no. >> the craving is so prominent. it's so enormous that they can't stop themselves. >> even if they want to stop they can't. their newly wired brain won't let them. it could help explain why some therapies to treat addiction aren't successful. take abstinence. >> i think it's egregious. you're telling someone whose brain is fundamentally changed