Research Conflicted When It Comes to Marijuana and Brain Function


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With voters in five states preparing to hit the polls this November to decide whether marijuana should be made legal—putting the United States in the position of possibly having more legal marijuana states than not—some reports have suggested that one of the biggest concerns right now is how all of this legal weed will impact the overall intelligence of the great American populous.

It seems that since federal government has remained hell bent throughout the years in refusing to allow any significant research to take place to study the therapeutic benefits of the cannabis plant, there are still those people out there who are convinced that the consumption of cannabis could have negative consequences on the human brain.

This is largely due to most of those folks growing up during a time when public service announcements ran during Saturday morning cartoons that not only insisted that marijuana was a dangerous and addictive drug but also that it would, in fact, fry brains.

Come to think of it, those non-creative prohibitionists are still trying to push that nonsense in 2016.

OK, sure, there have been studies that have shown a slight drop in IQ points in those people who began smoking marijuana in their younger years—during a time when the brain was still developing—but the researchers behind these finding concluded that there was nothing to suggest that people who started using marijuana in their adult lives experienced any cognitive decline.

Nevertheless, the study, which was published by researchers in New Zealand, has been the center of much controversy for the past few years because other scientific minds argue that it did not take into account a number of crucial factors, including upbringing and household financial status.

In fact, this research was responsible for inspiring Nicholas Jackson, senior statistician at the University of California, who had a heavy hand in a popular marijuana IQ study published earlier this year, to get to the bottom of all this “pot reduces intelligence” business by comparing twins. His concept was simple: By exploring two people with the same genetics, the same household, with the only difference being that one smokes marijuana, it should be easy to determine whether the stoner sibling was dumber than his sober counterpart.

Only the outcome of the study was not that cut-and-dry.

“If marijuana was causing IQ decline, what we would expect to see is that the twin who goes on and uses marijuana should have IQ deficits,” Jackson told NPR. “We don’t find that.”

Obviously, IQ points fluctuated for the sets of twins utilized in the study, but at the end of the day, researchers found no evidence that marijuana was transforming the stoned sibling into more of a degenerate than the other.

There is not likely a single marijuana user in the world who would dare say that his or her experience with the leaf has turned them into slobbering moron—most would argue that cannabis has expanded the scope of their intelligence by allowing them to become more introspective and self-aware. But you guessed it—there really is no concrete evidence to support this claim because the federal government simply does not support this type of research.

However, medical experts have said that what is typically being mistaken for a decline in brain function is actually just a marijuana user’s short-term memory taking a temporary vacation.

Dr. Mitch Earleywine, professor of psychology at the University of Albany, told NPR that while being stoned at school may prevent a student from learning a state capital, “when it comes to things that are more liquid intelligence, more fluid intelligence, they’re usually pretty good at those because it requires just intelligence in the moment, so to speak.”

Interestingly, the federal government is preparing to launch a major research program to study the link, if any, between drug use during the formative years and a decline in brain function. Researchers with the Adolescent Brain and Cognitive Development Study (ABCD) will monitor thousands of 10-year-olds as they make the journey into early adulthood, utilizing neuroimaging technology to spot any discrepancies in the brain.

But for now, there doesn’t seem to be too much concern that the American population is destined to become a legion of red-eyed zombies as more states move to legalize in 2016. In fact, some of the latest polls coming from states with marijuana ballot measures up for consideration this November seem to indicate strong support—hardly the tale of a people frightened by the possibility of slipping further into cesspool of idiocy. [link: