Report Heavy marijuana use may cause poor memory and abnormal brain structure, study says

[tom_mai78101]

Teenagers who smoked marijuana daily for three years performed poorly on memory tasks and showed abnormal changes in brain structure, according to a Northwestern Medicine study.

Researchers in Chicago observed the brains of teenagers who were heavy users of marijuana. In those individuals, memory-related structures in the brain appeared to shrink and collapse inward, possibly indicating a decrease in neurons.

These abnormalities were recorded two years after the teens stopped using marijuana, possibly indicating long-term effects, and look similar to schizophrenia-related brain abnormalities.

The brains were shaped more abnormally for individuals who began marijuana use at a younger age, according to the reports, which suggest that memory regions of the brain are more susceptible to the drug at earlier ages.

The research was published in the December issue of Schizophrenia Bulletin.

Early Marijuana Use Results in Abnormal Brain Structure, Poor Memory - News Center

Teens who were heavy marijuana users - smoking it daily for about three years - had abnormal changes in their brain structures related to working memory and performed poorly on memory tasks, reports a new Northwestern Medicine study.

news.feinberg.northwestern.edu

 

[tom_mai78101]

Definition of "heavy":

From the paper: "quantity and biological markers of cannabis use were not collected". The authors report the control/CUD group used on average of 4 out of 5 days. It's also worth pointing out that the control marijuana using group was smallish, N=10. The outcome measure is shape of subcortical structures, which I know professionally to be difficult to do. In addition, this was performed on a 1.5T machine which is, in research terms, low field meaning a noisier image. These are not real criticisms just things that pop out at me, someone who does this for a living, as warranting further studies. The statistics are sound and likely the best information we have at the moment to answer this specific question (wrt schiz, I believe there are other papers out there for normal MJ users).

 

[ertaboy356b]

Too bad I don't believe it

 

[FireCat]

This isn't surprising.

 

[KMilz]

Was there a control group of peers that weren't cannabis users? I wonder not to argue the data, but to better consider it.

Edit: Oh, guess so.

 

[Zakyath]

well, what I find most alarming about this is that the comments on that site just won't accept that heavy use in children could have negative effects. "now the government owns PBS"? yeah right.

 

[Varine]

This isn't surprising at all. I don't know why everyone wants to believe that marijuana is some perfectly safe, non-drug thing with no addiction potential and is an automatic cure for everything. It's not, it has some medicinal properties just like heroin and cocaine, even meth in some cases, and negative effects when used in excess.