By Terry Franklin |  The Daily Chronic
March 20, 2015 8:46 AM

Prohibitionists keep circulating scare stories about marijuana, and people keep believing them.

Lurid tales of insanity and murder were quite effective in the 1930s. Seen now as ridiculous; yet nonetheless, modern tales, equally ridiculous, are widely accepted.

If marijuana actually caused some trouble — health problems, madness, violence, mental deficit, lasting effects after the immediate intoxication — ask yourself: Wouldn’t it be obvious? Tens of millions of people in this country partake of it. The vast majority use it in moderation, and live fulfilling lives as bankers, doctors, and presidents. Others, “worst cases,” use what is in most anyone’s opinion, too much. They aren’t hard to find. In other cultures, Jamaica comes to mind, significant percentages of the population smoke it daily for decades. If there was something there, we’d know it.

But as there isn’t, opponents of legalization search for more and more subtle effects. Something. Anything. They’ll make it sound dire, no matter how tiny.

Year after year, their “studies” come out to fool the gullible.

This would be laughable, if these propaganda pieces were not reported so uncritically in the media, and repeated by politicians to justify their cruel policies.

Modern drug studies are a perfect example of what Nobel Prize winning physicist Richard Feynman dismissed as “cargo cult science.” They seem to have all the trapping of science. They use a lot of jargon. They have charts and figures and technical photographs. Sometimes they even use impressive looking scientific machines. But in the end, they amount to so much voodoo.

Where to begin, when taking on this problem? Well, bias is a great starting point. That should always be a major red flag. In the U.S., marijuana studies are almost universally funded by the National Institute on Drug Abuse, a federal agency whose goal is to demonize marijuana. The researchers need to depend on them for continuing monetary support, quite an incentive for bias.

There is also cherry picking of data, small sample sizes, poorly designed controls, sloppy statistical methods, confounding variables, and that big bugaboo, correlation vs. causation.

A year or so ago, a big study in the news was one which correlated a heavy adolescent use with lower IQ test scores in later years. It was clearly meant to imply (and headline writers trumpeted): Marijuana harms your brain.

Even a brief deliberation will come up dozens of alternative possibilities: Maybe parents who don’t care if their kids “use heavily” also don’t instill in them a reverence for education? Maybe their socioeconomic group doesn’t excel in taking IQ tests? Maybe if you party too much, you don’t do your homework?

A big exciting field these days is brain research using Magnetic Resonant Imaging. An MRI machine is certainly a cool gadget — very “scientific” looking. What is not widely reported is how much criticism there is among scientists, urging their colleagues to be cautious about hyping dubious results.

After all, what an MRI sees is the quantum states of some atoms’ nuclei as they resonate when you shine radio waves on them. Whether any of that correlates with any real world element, such as brain function or human behavior, is wildly speculative.

The uncertainties were humorously demonstrated by a group of researchers from three prominent universities, who were able to come up with statistically significant behavioral data in an animal study using brain imaging — in which it didn’t seem to matter that the animal was dead.

This year’s crisis de jour is Dr. Breiter’s alarming study, which claims to have found differences in adolescent brain MRI images after marijuana is smoked. (Though the word “difference” is often replaced by the more loaded word “abnormality” when prohibitionists want to push their point in the media.)

The finding has been widely reported. This kind of work is so preliminary that it would never be reported at all in any area of science where there was no political agenda involved. It would need to be shown that it was repeatable — at the very least. When you are dealing with something this slight and subtle, and so close to the level of noise, the question is often not even “does what I am seeing have any meaning?” The question may be “am I seeing anything at all?”

Marijuana “studies” are much more likely to befuddle the mind than marijuana itself.

It is probably too much to expect that people in the media will actually read and ponder the actual journal article they are reporting on, rather than just copying the talking points in the press release handed them by the prohibitionists. But it wouldn’t be hard at all to go to the internet, look up “brain imaging criticism,” find an article by a real scientist, and call him for a second opinion.

Barring that, the public is just going to need to fall back on their own critical thinking skills.

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