The following article from U.S. News and World Report isn't a surprise to me.
It confirms what we already know from research over the past 15 years about the effects of substances on the developing child's brain. The kids I see in my practice usually focus on the idea that "it's only pot" and/or "it's not addicting" (not true, but that's another topic for another time). They don’t acknowledge any effects on their own brain development.
Parents who may have smoked marijuana when they were growing up may be conflicted about their own experience and knowledge of whether marijuana really is harmful. Marijuana use in our culture has become more accepted, aided in part by the recognized medicinal uses of marijuana. As a parent, what’s important is to be able to offer kids accurate, unbiased information like this when we discuss the choices our children make today.
We've come a long way from "Just say no"!
By the way, the “executive functions” that the article refers to are the same brain information processing skills that are impaired by ADHD.
For more good information on marijuana use and kids, seeNATIONAL INSTITUTE ON DRUG ABUSE INFO ON MARIJUANA