The Physics Police

The Physics Police

Friday, October 18, 2013

Rats, Oreos, and Drugs

The science media circus has pitched its tent around a Connecticut College News article claiming:
Connecticut College students and a professor of psychology have found “America’s favorite cookie” is just as addictive as cocaine – at least for lab rats.
This is, of course, a false conclusion. The research by Joseph Schroeder and his students actually shows that "conditioned place preference" can be accomplished by administering addictive drugs or a food reward.

No direct comparison was made between the drugs and food.

In the presentation abstract, the researchers draw a subtly different conclusion than the article:
These findings suggest that high fat/sugar foods and drugs of abuse trigger brain addictive processes to the same degree and lend support to the hypothesis that maladaptive eating behaviors contributing to obesity can be compared to drug addiction.  
Maladaptive eating behaviors can be compared to drug addiction. This is fairly obvious, for anyone who has ever seen someone eat a whole pint of ice cream. Or eaten one, themselves.

Nobody would question the fact that food is a profound motivator. Motivation and reward are involved in addiction. But the claim that one substance is "just as addictive as" another requires evidence. This research provides no such evidence. They didn't even look for it.

Here's how the study was conducted:
On one side of a maze, they would give hungry rats Oreos and on the other, they would give them a control – in this case, rice cakes... Then, they would give the rats the option of spending time on either side of the maze and measure how long they would spend on the side where they were typically fed Oreos.

They compared the results of the Oreo and rice cake test with results from rats that were given an injection of cocaine or morphine, known addictive substances, on one side of the maze and a shot of saline on the other. Professor Schroeder is licensed by the U.S. Drug Enforcement Administration to purchase and use controlled substances for research.

The research showed the rats conditioned with Oreos spent as much time on the “drug” side of the maze as the rats conditioned with cocaine or morphine.
This is called "conditioned place preference" and is a staple of High School science projects. The conditioning worked equally well for both drugs and Oreos, so they are both equally addictive, right?

Wrong!

All that has been demonstrated is that drugs and Oreos both work equally well for conditioned place preference. You can't extrapolate from this to addiction!

Rats are smart. They quickly identify areas on a maze with reward. It could be cheese. It could be a shot of morphine. It could be a chocolate chip cookie. Or an oatmeal cookie. Or an Oreo cookie.

If the rats ran the maze equally well for cheese as Oreos, would we, by the transitive property of addiction, conclude that cheese is "just as addictive" as cocaine? I think not.

If you wanted to actually compare Oreos to drugs, you would have to administer Oreo plus the saline control on one side of the maze, and drugs plus the control cracker on the other side. The researchers didn't perform this test.

Why not? Because they weren't studying the relative addictive properties of drugs and food in the first place. They were studying the nucleus accumbens!
Stimulation of the nucleus accumbens by addictive substances, including high fat/sugar foods triggers expression of immediate early genes, the measurement of which can be used as an indicator of cellular activation. 
Their experimental design was setup to demonstrate this hypothesis.

But "Nucleus accumbens C-Fos expression is correlated with conditioned place preference" isn't a headline that pops. So they added misleading language into their conclusion, and hooked up with Amy Martin, the Manager of Media Relations at Connecticut College.

Together, they produced this garbage news article, which was quickly picked up by the media.

Now, we have crazy headlines like Will Oreos Be Outlawed Next? and Lab rats find Oreos more pleasurable than drugs. This isn't just annoying and wrong. It's dangerous. The constant stream of bad science from the media harms people's brains. Bad science teaches people bad thinking patterns. The end results are bad decisions that harm individuals and the society as a whole. This is not just about one brand of cookies. It's not okay to lie to people and call it science.

Injecting Oreos with drugs because, why not?

Oh, and where was this study published, you ask?

Nowhere. It's not peer-reviewed. It's unpublished.

It's not even science.

It's careerism and dishonesty.

Okay, now I want Oreos.

UPDATE: I called Deborah MacDonnell, the Director of Public Relations at Connecticut College, and voiced my concerns about the article. She told me that "Connecticut College stands behind [Joseph Schroeder's] research." So much for their reputation.

1 comment:

  1. Just heard about this. Thanks for explaining the details.

    ReplyDelete