|Aspen Daily News|
|Keith Stroup, who founded the National Organization for the Reform of Marijuana Laws (NORML) in 1970, takes a smoke break for mental sharpness at the NORML convention in Aspen, Colorado in 2008.|
Researchers looked at a large sample of 8,992 men who "used drugs," mostly cannabis, at age 42 and then again at age 50, reports Dennis Romero at LA Weekly. The men were tested to measure their level of brain functioning.
Surprise, surprise -- the Brits who had used illegal drugs did just as well -- or slightly better! -- than the chaps who had never "used drugs" at all.
When current and past drug users were lumped together as one group, their scores tended to be better than those of non-users. That advantage was small, researchers said, and might be due to the fact that people who have tried drugs tend to be better educated than those who haven't.
"A positive association was observed between ever (past or current) illicit drug use and cognitive functioning," the study's authors concluded in the American Journal of Epidemiology.
Marijuana was by far the most commonly used substance among participants of the study -- performed by Alex Dregan of King's College London, reports Amy Norton at Reuters.
|Dr. John Halpern, Harvard Medical School: "This is what you'd expect to see"|
"At the population level, it does not appear that current illicit drug use is associated with impaired cognitive functioning in early middle age," an abstract of the study concludes.
Other drugs that were asked about included amphetamines, LSD, psilocybin mushrooms, cocaine and ecstasy, but only three to eight percent of study participants said they'd ever tried those.
A small subset of participants who claimed they had been treated for their drug use -- which could suggest heavy or addicted drug use, or perhaps harder drugs of choice -- did not fare as well cognitively at 50, but there were so few of them, it was impossible to draw meaningful conclusions, the study's authors said.
"In a Western population of occasional drug users, this is what you'd expect to see," said John Halpern, a Harvard Medical School psychiatrist who has studied the potential cognitive effects of drugs.
"In some ways, this is not surprising," Dr. Halpern said. "The brain is resilient."
The study's findings support the idea that the effects of marijuana and perhaps other drugs are only temporary, and that cognition isn't damaged once the effects wear off.