Regular marijuana use bad for teens' brains

Frequent marijuana use can have a significant negative effect on the brains of teenagers and young adults, including cognitive decline, poor attention and memory, and decreased IQ, according to psychologists discussing public health implications of marijuana legalization at the American Psychological Association's 122nd Annual Convention.

"It needs to be emphasized that regular cannabis use, which we consider once a week, is not safe and may result in addiction and neurocognitive damage, especially in youth," said Krista Lisdahl, PhD, director of the brain imaging and neuropsychology lab at University of Wisconsin-Milwaukee.

Marijuana use is increasing, according to Lisdahl, who pointed to a 2012 study showing that 6.5 percent of high school seniors reported smoking daily, up from 2.4 percent in 1993. Additionally, 31 percent of (ages 18 to 25) reported using marijuana in the last month. People who have become addicted to marijuana can lose an average of six IQ points by adulthood, according to Lisdahl, referring to a 2012 longitudinal study of 1,037 participants who were followed from birth to age 38.

Brain imaging studies of regular marijuana users have shown significant changes in their brain structure, particularly among adolescents, Lisdahl said. Abnormalities in the brain's gray matter, which is associated with intelligence, have been found in 16- to 19-year-olds who increased their marijuana use in the past year, she said. These findings remained even after researchers controlled for major medical conditions, prenatal drug exposure, developmental delays and learning disabilities, she added.

"When considering legalization, policymakers need to address ways to prevent easy access to marijuana and provide additional treatment funding for adolescent and young adult users," she said. She also recommended that legislators consider regulating levels of tetrahydrocannabinol, or THC, the major psychoactive chemical in marijuana, in order to reduce potential neurocognitive effects.

Some legalized forms of marijuana have higher levels of THC than other strains, said Alan Budney, PhD, of Dartmouth College. THC is responsible for most of marijuana's psychological effects. Some research has shown that frequent use of high potency THC can increase risk of acute and future problems with depression, anxiety and psychosis. "Recent studies suggest that this relationship between marijuana and mental illness may be moderated by how often marijuana is used and potency of the substance," Budney said. "Unfortunately, much of what we know from earlier research is based on with much lower doses of THC than are commonly used today." Current treatments for marijuana addiction among adolescents, such as brief school interventions and outpatient counseling, can be helpful but more research is needed to develop more effective strategies and interventions, he added.

Additionally, people's acceptance of legalized use appears to have an effect on adolescents' perception of the drug's risks, according to Bettina Friese, PhD, of the Pacific Institute for Research and Evaluation in California. She presented results from a 2013 study of 17,482 teenagers in Montana, which found marijuana use among teenagers was higher in counties where larger numbers of people voted to legalize medical marijuana in 2004. In addition, teens in counties with more votes for the legalization of medical marijuana perceived marijuana use to be less risky. The research findings suggest that a more accepting attitude toward medical marijuana may have a greater effect on marijuana use among teens than the actual number of medical marijuana licenses available, Friese said.

More information: Session 3163: "Considering Cannabis? Potential Public Health Implications of Marijuana Legalization," Symposium, Saturday, 10 a.m. to 11:50 a.m. EDT, Room 150B, Walter E. Washington Convention Center, 801 Mount Vernon Pl., NW, Washington, D.C.

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ar18
3 / 5 (4) Aug 09, 2014
A 38-year long study? Marijuana wasn't legal 38 years ago, so just where did the researchers get all these *illegal* users of Marijuana to volunteer for this study? And how did the researchers get permission to study *illegal* users without penalty? How do they know the users ONLY used Marijuana? Is this just another case of dishonest propaganda like the "Reefer Madness" nonsense of the 20th Century?
Brian_Kelly
not rated yet Aug 09, 2014
There is absolutely no doubt now that the majority of Americans want to completely legalize marijuana nationwide. Our numbers grow on a daily basis.

The prohibitionist view on marijuana is the viewpoint of a minority of Americans.. It is based upon decades of lies and propaganda put forth largely by The National Institute On Drug Abuse, commonly referred to as NIDA .

"While U.S. officials defend their monopoly, critics say the government is hogging all the pot and giving it mainly to researchers who want to find harms linked to the drug.

U.S. officials say the federal government must be the sole supplier of legal marijuana in order to comply with a 1961 international drug-control treaty. But they admit they've done relatively little to fund pot research projects looking for marijuana's benefits, following their mandate to focus on abuse and addiction.

"We've been studying marijuana since our inception. Of course, the large majority of that research has been on the deleterious effects, the harmful effects, on cognition, behavior and so forth," said Steven Gust, special assistant to the director at the National Institute on Drug Abuse, which was created in 1974."
Read more here: http://www.mcclat...m/201...

Each and every tired old NIDA has propagated has been thoroughly proven false by both science and society.

Their tired old rhetoric no longer holds any validity. The majority of Americans have seen through the sham of marijuana prohibition in this day and age. The number of prohibitionists left shrinks on a daily basis.

With their credibility shattered, and their not so hidden agendas visible to a much wiser public, what's left for The National Institute On Drug Abuse to do?

Maybe, just come to terms with the fact that Marijuana Legalization Nationwide is an inevitable reality that's approaching much sooner than prohibitionists think, and there is nothing they can do to stop it!

Legalize Nationwide!...and Support All Marijuana Legalization Efforts!
kochevnik
not rated yet Aug 09, 2014
"marijuana addiction" That's all I needed to read. Must be a gateway to vegetarianism, creative writing classes and Facebook
Brian_Kelly
not rated yet Aug 09, 2014
If you really want to protect families from a drug proven to destroy lives and families, then you should be up in arms, protesting the legality of booze.

Alcohol is the number one cause for traffic fatalities and domestic violence by a huge landslide.
Why doesn't that concern you even more?

Regarding "The Children",

Let's not use "The Children" as an excuse to prohibit and criminalize adult use of a natural plant far less dangerous than perfectly legal alcohol because nobody condones child use, and this is about allowing adults only to choose marijuana.

It's our responsibility as parents by to educate our children on drug use. It's not the government's job to force Draconian Marijuana Laws upon every adult citizen under the guise of protecting "The Children".

What message are we sending our children when it is easier for them to obtain marijuana now with it being illegal than it is for them to buy alcohol?

It doesn't take the intellect of a genius to understand that stores card kids for I.D. Thugs and gang members do not. They also push the real hard drugs on children. Stores do not.

Marijuana legalization will make it harder for children to obtain it.

What message does it send our children when the President of The United States himself alongside a long list of successful people openly admit regular pot use at one time or another in their lives?

While we tell our kids how it will ruin their futures, and then insure so, by allowing our government to to jail our children and give them permanent criminal records when they get caught with a little Marijuana. Especially, if they are the wrong skin color or from the "wrong neighborhood". Which in turn, ruins their chances of employment for life.

The Prohibition of Marijuana is the wrong message to send our children while we glorify, advertise and promote the much more dangerous use of alcohol like it's an all American pastime.

The worst thing about marijuana and our children is what happens to them when they get caught up in the criminal justice system due to it's prohibition.

Protect "The Children" and Our Neighborhoods Through The Legalization and Regulation of Marijuana Nationwide!
h20dr
not rated yet Aug 09, 2014
Reading through the study, it is full of "may suggest", "needs further study", assumptions, anecdotal and subjective evidence gleaned from people who associated with the study subject and probably imbibed themselves- with the subject who was being studied. No doubt, there are likely lasting effects from heavy use over the years but there is still too little known about the brain to conclude any meaningful insight, imho.
Shootist
not rated yet Aug 09, 2014
Yes. Teen's personalities haven't fully actualized.

No pot for you.
alfie_null
5 / 5 (1) Aug 10, 2014
There is absolutely no doubt now that the majority of Americans want to completely legalize marijuana nationwide. Our numbers grow on a daily basis. . . .

Be more accurate to say increasing numbers don't object. Way different from embracing as you imply.

Regarding your disparagement of efforts expended by the government to identify benefits - how many pot users care a whit about alleged benefits? Or care to spend resources on such? How many are in it for anything other than recreation? How about you? Use it recreationally? Don't be disingenuous.

Being conservative, slow, careful about decriminalization is a prudent course. I wonder about your motivation with your reckless adoption of this psychoactive drug about which we know little.

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