Good news! “Zoning out” a crucial mental state


  • Stop Paying Attention: Zoning Out Is a Crucial Mental State – “When our minds wander, we lose touch with the outside world [...] we are more likely to make mistakes, fail to encode memories, or miss a connection. [...] [Scientists] tested the effect of zoning out by having a test group read a Sherlock Holmes mystery in which a villain used a pseudonym. As people were reading the passages discussing this fact, the researchers checked their state of attentiveness. Just 30 percent of the people who were zoning out at the key moments could give the villain’s pseudonym, while 61 percent of the people who weren’t zoning out at those moments succeeded. [...] The regions of the brain that become active during mind wandering belong to two important networks: [the executive control system, and the default network.]“

Both of these networks are used for thinking about goal directed behavior and the future. The article suggests that mind-wandering may lead to those Eureka!-like moments of spontaneous insight that may not occur when attentive to the present.


New press release “tries,” but still botches review of McGill “Marijuana” Study


BusinessWeek, among others, published a new press release of the same McGill University “marijuana” study which, while at least mentioning that it was done on animals, still failed to mention several points — one of them being that the study itself did not even use marijuana, and in this case has the particularly large blight of outright stating that the rats were given cannabis, when in fact, they were given WIN 55212-2, a synthetic compound that is a stronger agonist of CB1 receptors  than tetrahydrocannabinol, the main active ingredient of marijuana (though there are a few others).

If any of you recall, I made a post entitled “An unsurprisingly disingenuous look at marijuana” criticizing NOT the study itself, but the strong misrepresentation it was given on multiple popular science websites.

Most of the ORIGINAL press this study got fell short in mentioning:

  • The study was in animals.
  • That the anxiety-like/depressive behavioral symptoms were not demonstrated in all of the results, and the study failed to demonstrate the same effects in the “open field test.”
  • That even the “low” dose may have been somewhat high, and thus not a good comparison for smoked marijuana, had it even been marijuana they tested in the first place.
  • And finally… That the study didn’t use marijuana, but instead a synthetic compound called WIN 55212-2, which has demonstrated both a stronger affinity for CB1 receptors than THC, and is structurally different. (which the news press release has done no better at)

While I was quite pleasantly surprised that BusinessWeek (and the others hosting this new, updated press release), took the opportunity to mention that the study wasn’t done in humans:

Although the finding stems solely from work conducted with adolescent and adult lab rats — not yet replicated among humans

They still fell short in all other respects mentioned earlier, and in fact, explicitly and incorrectly stated that the rats were given cannabis, as shown:

To assess the role cannabis may play on adolescent brain development, for 20 days — a period characterized as “prolonged exposure” — adolescent rats were given daily injections of either a low-dose (0.2 milligrams/kilograms) or high-dose (1.0 milligrams/kilograms) of cannabis.

Round 2, still can’t get it right? Fire your PR department, McGill! Honestly.  A little proofreading, or a little honest (choose your slant) can go a long way.


An unsurprisingly disingenuous look at “marijuana”


As many of my readers know, I like to pull a lot of breaking science news from Eurekalert. One particular article today has drawn my attention, and I’d like to point out to the very disingenuous manner in which it was presented to the lay audience, who may lack the time, educational background, or simply a healthy amount of skepticism to see the spin.

Entitled “Cannabis and Adolescence,” the press release from Eurekalert is as follows:

Montreal, December 17, 2009 – Canadian teenagers are among the largest consumers of cannabis worldwide. The damaging effects of this illicit drug on young brains are worse than originally thought, according to new research by Dr. Gabriella Gobbi, a psychiatric researcher from the Research Institute of the McGill University Health Centre. The new study, published in Neurobiology of Disease, suggests that daily consumption of cannabis in teens can cause depression and anxiety, and have an irreversible long-term effect on the brain. [...]

“Teenagers who are exposed to cannabis have decreased serotonin transmission, which leads to mood disorders, as well as increased norepinephrine transmission, which leads to greater long-term susceptibility to stress,” Dr. Gobbi stated. [...]

It is also the first study to demonstrate that cannabis consumption causes more serious damage during adolescence than adulthood.

Fair enough. Cannabis effects some neurotransmitters and stuff, and affects the development of the brain. It sounds plausible…

…except the actual study was neither performed on humans nor even involved any actual compounds present in marijuana.

This study (actual pubmed link) used adolescent rats and a compound known as WIN 55,212-2. WIN 55,212-2 is known to both be stronger in its affinity for CB1 receptors than marijuana, and beside that structurally quite different.

Mentioned in the actual paper, but not in the “press release” was that the study did not find that exposure to WIN55,212-2 influenced anxiety-related behaviors, at least not in all of the assays. The elevated plus maze test results did not show an increase in basal level anxiety. In other words, the adolescent exposure to this highly-cb1-agonizing drug did not effect the rats propensity to visit an “open arm” at all. Nor was chronic, daily exposure to WIN 55,212-2 found to effect the rats behavior in the open field test. Both of these tests are considered extremely important in assessing a rats propensity towards anxiety/depressive-like behavior.

The rats did show a reduced tendency to feed in new environments after high exposure to the marijuana-analogue, in a task known as the novelty suppressed feeding task.

However, what about DOSING?

Grabbed from the always helpful reddit commentary:

Lets take a look at the dosage.”the adolescent exposure group received for 20 days once-a-day i.p. injections of a low dose (0.2 mg/kg) or a high dose (1 mg/kg) of WIN55,212-2 or the vehicle.” Lets take an average human weighing 80kg. And an average rat weighing .5kg

2mg dose to a human, divided by 80kg is .025 mg/kg the LOW dose to the rat was .1mg/kg intravenous injection. that’s 4 times the human oral ingestion to get high. the high dose was .5 mg/kg thats 20 times the human oral ingestion to get high.

Injection should be using A LOT less than an oral ingestion, correct?

Something seems off with the dosages, but I’m not a scientist. Is there anything wrong with my reasoning?

No, sir, the dosing does sound a wee bit high to correlate too strongly to adolescent smoking.

Now, to be fair:
Animal model systems are an essential component to research, as are chemical analogues, and inferences can be made using these. The fact that these techniques were used doesn’t in and of itself invalidate the underlying premise that habitual use of any drug can change human behavior. Nor should data be completely be disregarded simply because one aspect lacks in robustness, but given the actual content of the paper I’ve got to wonder — did the P.R. department even read the paper before typing up their blurb? At what point does over-simplification become deception and misdirection?