A New Study Questions The Link Between Teen Pot Smoking And IQ Decline

A New Study Questions The Link Between Teen Pot Smoking And IQ Decline

NEW YORK (AP) — A new analysis is challenging the idea that smoking marijuana during adolescence can lead to declines in intelligence.

Instead, the new study says, pot smoking may be merely a symptom of something else that's really responsible for a brainpower effect seen in some previous research.

I have been saying this is a likely possibility for a LONG time now. It's nice to see some corroborating evidence surface that its true.

It's not clear what that other factor is, said Joshua Isen, an author of the analysis. But an adolescent at risk for smoking pot "is probably going to show this IQ drop regardless of whether he or she is actually smoking marijuana," said Isen, a lecturer in psychology at Loyola Marymount University in Los Angeles.

So in other words, marijuana is likely a SYMPTOM of a greater problem where IQ dropping is also a related symptom. This could give the appearance of correlation equaling causation, but as we can see here, there can be exceptions. The article outlines the process the study went through to determine their results, so I'll post it below:

For the new work, the researchers examined data that had been collected for two big U.S. studies of twins. They focused on 3,066 participants who were given a battery of intelligence tests at ages 9 to 12 — before any of them had used marijuana — and again at ages 17 to 20.

They tracked changes in the test scores and studied whether those trajectories were worse for marijuana users than for non-users. Most tests revealed no difference between the two groups, but users did fare more poorly than abstainers in tests of vocabulary and general knowledge.

If smoking pot harmed test scores, the researchers reasoned, people who'd smoked more pot should show poorer trends than those who'd smoked less. But that's not what the data revealed. Among users, those who'd smoked more than 30 times or used it daily for more than a six-month stretch didn't do worse.

The study also looked at 290 pairs of twins in which one had used marijuana and the other had not. The members of each pair had grown up together and 137 sets were identical twins so they shared the same DNA. Again, the pot users did not fare worse than their abstaining twin siblings.

So, the researchers concluded, pot smoking itself does not appear responsible for declines in test scores. Isen noted, however, that the work says nothing about other potential harmful consequences of smoking marijuana in adolescence.

Hey. I'm all for keeping the minimum smoking age for places that have legalized it at 21, but it's looking like the reasoning for doing so is flawed. In any case, as always legalize freedom! And mind the T&C's please, let's not get this thread shutdown.

a reply to: Krazysh0t

Imo, what declines is motivation, not IQ. Less motivation to study might lessen your IQ.

But being stoned might help you discover your true motivation as well. Being stoned all the time isn't good for you.

All things in Moderation…

users did fare more poorly than abstainers in tests of vocabulary and general knowledge.

They appear to be talking about "active users" in this quote as opposed to the twins study where the term "had used" was needed.

No reason why the results should be that much different than alcohol consumption.

For much more comprehensive analysis we can watch the longer term trends of legalization in test states like Colorado.

a reply to: intrptr

Well there was a study or two a year or two back that linked small levels of IQ dropping to marijuana usage during teenage years. When it (they) came out, I was saying it was likely that IQ dropping AND marijuana use were symptoms of the same problem instead of have a cause and effect relationship with each other.

a reply to: intrptr

Yeah and the black man always scores lower on an IQ test, the IQ test was made for the white man

hah how about alcohol? tobacco? watching tv? being lazy?

this is propaganda. unless you can show that a chemical in cannabis actually kills brain cells, this is not good science.

just personally speaking for myself, pot has made me more patient and more skeptic. It breaks the ego and makes you realize you are not the center of the world.

a reply to: vjr1113

But it's saying that chemicals in cannabis AREN'T killing brain cells...

a reply to: Krazysh0t

well then i dont really care for non-science, its just opinion

a reply to: Krazysh0t

interesting questions this is bringing up. I'm glad they are questioning the supposed link between smoking cannabis and IQ decline.

Basically, after reading this it demonstrates that those who smoked pot (even if they were twins with the same dna) show no difference in their testing abilities.

Some studies have shown that it actually helps cognitive functioning in certain groups of people (middle-aged in this case):

For the study, roughly 9,000 participants were surveyed at age 42 on their drug use, and then surveyed again at age 50, and were tested using various cognitive functioning tests. Researchers found that those who had a history of, and currently used illicit drugs (with cannabis by far being the most popular), performed either as well, or better in these test.

Researchers found that “A positive association was observed between ever (past or current) illicit drug use and cognitive functioning.”

www.theweedblog.com...

Cool thread KS

a reply to: vjr1113

So you only accept information saying that cannabis kills brain cells? Isn't that biased?

originally posted by: raypsi13
a reply to: intrptr

Yeah and the black man always scores lower on an IQ test, the IQ test was made for the white man

No argument there.

a reply to: FamCore

Yea, when it comes to marijuana, I don't accept ANY negative long standing accepted consensus on the plant. There hasn't been enough research done for it and most of the negative things we've thought how the plant worked have turned out to be lies, exaggerations, or assumptions. That's why I was doubtful of the findings of the original studies.

originally posted by: Krazysh0t
a reply to: vjr1113

So you only accept information saying that cannabis kills brain cells? Isn't that biased?

yea i only accept hard evidence. if you're gonna say pot = lower IQ. prove it. by your logic, breathing has a correlation with lower IQ. bad science,

a reply to: Krazysh0t

Krazyshot this is the one area, i offer zero retort and agree with you 100%, the amount of hysteria about drugs (and i do not limit it to just pot) is mind numbing. I support a legalization of all drugs, and decriminalizing and also more support centers for rehabilitation in the event of addiction.

a reply to: vjr1113

But I'm NOT saying that pot = lower IQ. I'm saying the opposite.

originally posted by: TechniXcality
a reply to: Krazysh0t

Krazyshot this is the one area, i offer zero retort and agree with you 100%, the amount of hysteria about drugs (and i do not limit it to just pot) is mind numbing. I support a legalization of all drugs, and decriminalizing and also more support centers for rehabilitation in the event of addiction.

I support the decriminalization of all drugs. No one should be jailed for using. However, I'm all for keeping sales of certain drugs illegal. You know, the very destructive variety? Or at the very least, have them regulated like cigarettes with EXTREME restrictions on how sellers can advertise if the drugs have to be legalized.

Even if smoking it made a person dumber than hell, I could care less if someone else uses it.

There should be no laws regarding what a person does with their own body.

a reply to: Krazysh0t

lol that title triggered me hard, well my points are still valid just direct them to the right people. i should get some sleep

a reply to: Krazysh0t

Yes I am with you..

Ironically the very destructive drugs are legal and controlled but with one caveat, you have to Goto a legal drugs dealer otherwise known as a doctor. this mess all of it , has a direct arrow to our governments jackbooted policy's and white and black handling of morality, they say we do not legislate Christian principals and I say that's bull# we absolutely do. I don't deny that other drugs can have a serious consequence on your health (through repeated use, or even occasionally the first time such as coc aine) I also understand criminalizing the use of these substances is Idiocracy at its finest and does nothing to circumvent the destruction caused to the individual who becomes addicted. It's all backwards decriminalization and education(not propaganda) is where the" war on drugs" starts and ends.

My nephew lived with me for a year when he was 19. His best friend came over quite often for dinner.

I would sit at the table with them and be delighted with how intelligent and funny they were, such delightful dinner companions, and would marvel at their humor and cleverness.

THEN they would go out to the garage for a little while. When they came back to the table, it was like I was having desert with Beavis and Butthead. Big difference.

I hated it.