Discovered: Lighting up might not lead to dumbing down; playing music can put you on a natural high; black carbon is twice as bad as we thought; evidence that obesity is inherited.
Marijuana might not lower teen IQs. Last summer, a study making the rounds in mainstream media (including this very site) purported to show evidence that teens who frequently smoked pot would grow up to have lower IQs. But part of the scientific process involves revisiting studies with such bold claims, and upon further inspection a Norwegian researcher writing in the the Proceedings of the National Academy of Sciences finds no convincing evidence that pot makes youngsters dumb. Ole Rogeberg of the Ragnar Frisch Centre for Economic Research writes, "Simulation results suggest that SES-related cognitive decline is sufficient to reproduce" those earlier findings. Basically, Rogeberg is saying that those IQ declines earlier researchers saw were normal in subjects' socioeconomic backgrounds, whether they smoked pot or not. [Los Angeles Times]
Music really can put you on a natural high. In semi-related news, musicians who talk about the transcendent high they get by playing in front of a crowd are only half exaggerating. A study published in Evolutionary Psychology shows that performing music gives the body an opiate massage similar to the "runner's high." Oxford psychology professor Robin Dunbar found that endorphins released while playing music increased pain tolerance. And a sudden rush of endorphins also often correspond to a slight high. "Psychologically, endorphin release is experienced as a mild opiate 'high,' a corresponding feeling of well-being, and light analgesia," writes Dunbar. [The Atlantic]
We now realize just how bad black carbon is for the environment. Black carbon has long been understood as a culprit in global warming, but new research published in the Journal of Geophysical Research-Atmospheres suggests that it's two times worse than we thought. Black carbon, also known as soot, is that stuff emitted by diesel engines and burning wood. Only carbon dioxide is worse when it comes to global warming emissions. "The large conclusion is that forcing due to black carbon in the atmosphere is larger," says lead author Sarah Doherty. "The value the IPCC gave in their 4th assessment report in 2007 is half of what we are presenting in this report — it's a little bit shocking." [BBC News]
A chemical candidate for how obesity gets inherited. People who explain their waistlines by saying, "it's genetic," can now get a little more specific. "It's the accumulation of tributyltin I inherited from my parents," they can say if the situation calls for hard science. (That's TRY-beautil-tin.) So says the theory behind a new study from UC Irvine's Raquel Chamorro-García and her colleagues. They studied obesity in mice and discovered that feeding subjects tributyltin caused them to get fat. And it caused their children—even their grandchildren—to pack on the pounds, too. "The findings confirmed previous work showing that tributyltin affects the function of a gene that regulates body fat production and reprograms certain stem cells to become fat cells rather than bone cells," reports Science News' Erin Wayman. [Science News]