Addiction and self-control

The NYT reports on Carl Hart's work studying the self-control of crack and meth addicts. Maybe somebody can tell me how you get away with a study like this:

Dr. Hart recruited addicts by advertising in The Village Voice, offering them a chance to make $950 while smoking crack made from pharmaceutical-grade cocaine. Most of the respondents, like the addicts he knew growing up in Miami, were black men from low-income neighborhoods. To participate, they had to live in a hospital ward for several weeks during the experiment.

At the start of each day, as researchers watched behind a one-way mirror, a nurse would place a certain amount of crack in a pipe — the dose varied daily — and light it. While smoking, the participant was blindfolded so he couldn’t see the size of that day’s dose.

Then, after that sample of crack to start the day, each participant would be offered more opportunities during the day to smoke the same dose of crack. But each time the offer was made, the participants could also opt for a different reward that they could collect when they eventually left the hospital. Sometimes the reward was \$5 in cash, and sometimes it was a \$5 voucher for merchandise at a store.

When the dose of crack was fairly high, the subject would typically choose to keep smoking crack during the day. But when the dose was smaller, he was more likely to pass it up for the \$5 in cash or voucher.

How did that get approved? I'm not saying this was abusive, but it is a little startling.

At any rate:

He also found that when he raised the alternative reward to \$20, every single addict, of meth and crack alike, chose the cash. They knew they wouldn’t receive it until the experiment ended weeks later, but they were still willing to pass up an immediate high.

Dalrymple and others claimed that addicts generally had more self-control than most (including themselves) believe. This seems to validate their observations.

But you can conclude too much from Hart's studies. The population is self-selected, of course, biased in favor of people who have the confidence to deliberately leave their home environments. They are now in a completely new and controlled environment, without any of the normal influences that make up a lot of what we think of as natural choices. (To what extent that environment is a product of your own choices is a more complicated issue. I can't choose family or neighbors, but I chose friends and what I listened to and watched, and that history has to produce some feedback.) And the rewards offered in the hospital are more clear-cut and reliable than the longer-term and chancy rewards of self-control in the hood, where there's a lot of random danger and crab-bucket trouble.