Crack and meth addicts probably aren't as addicted as you think

Addiction — in the neuro-biological can't-get-enough-dopamine sense — might not be as powerful as pop culture would have us believe. A Columbia University psychology researcher has found that only about 20% of meth and crack users actually end up physiologically addicted. And, even those people are capable of making rational choices — including denying themselves a hit of their drug-of-choice in favor of a delayed monetary award. Based on his research, Carl Hart believes that drug use is merely a symptom of a life that's gone awry for other, more systemic, reasons.