That little artcle was about the brain's almost unlimited capacity for learning, which seems to drop off after the age of 12. That doesn't mean kids can't and don't learn after that. They certainly can. But the uncanny, almost spongelike ability to soak up languages and various other verbal and math skills isn't quite the same after adolescence that it is before. Certain neural pathways shut down and dont continue to expand in the same way that they do before the age of 12.

They used to think the human brain was through developing by 17 or 18, but more recent studies have shown that the final finishing touches are still being put on the frontal lobe, the area that governs reasoning and judgment and impulse control, well in to the early 20s. So now they say the brain's probably not to its fully developed state until 23 or 25.

The precaution against marijuana use until a brain is fully formed is because no one really knows what sort of effects it may have on those developing neural pathways and on the final stages of frontal lobe development. There've been some small-scale studies that have shown moderate cannabis use doesn't appear to interfere with learning or memory. But no one with any sense is going to do a large-scale study of the effects of cannabis on the brains of teenagers simply because it could be too risky. What if, in large-scale testing, they discovered cannabis did indeed affect intellectual development? Ethical scientists don't test substances on teenaged kids, just as they don't test them on fetuses, babies or small children. The stakes are simply too high.

I wish kids would wait to smoke weed till they're 21 or so, but hey, I didn't. And I turned out pretty well in the smarts department. Who knows, though? I might have been an absolute whiz-kid if I'd laid off the grass till was finished with college!
birdgirl73 Reviewed by birdgirl73 on . Avoid marijuana until of age? Well I was always told that marijuana is harmless and really poses no harm but should be avoided until the brain is done developing. I just was wondering why exactly is that? I always heard that but never got an explanation for it. Does anyone know why? Does it stunt anything like growth or what... Rating: 5