Smoking marijuana only affects your IQ if you care about your stupid IQ
A study claiming that pot use in youth has long-term cognitive effects is being challenged. The originalstudy, published last year in the Proceedings of the National Academy of Sciences (PNAS), found that smoking marijuana as a teenager may be associated with IQ declines by middle age. The new study, published in the same journal on Monday (January 14), said that IQ declines were likely a product of socioeconomic status, Nature reported.
“Although it would be too strong to say that the results have been discredited, the methodology is flawed and the causal inference drawn from the results premature,” Ole Røgeberg, the sole author of the new study and an economist at The Ragnar Frisch Centre for Economic Research in Oslo, wrote in the paper.
What does an IQ score even mean?
The IQ test is one of psychology’s most widely used tools. However, IQ testing has been criticized for a number of factors–including possible bias regarding race and economic level. Critics say IQ tests may not measure imagination or moral character either, according to the .American Psychological Association, or APA.
IQ tests have been criticized by researchers and educators for not taking into consideration race, gender, class and culture, the APA says. The tests appear geared toward white, upper-class males–who tend to score better on certain tests. Other criticisms include a minimization within the tests of practical everyday know-how, the importance of creativity and having a well-rounded character, according to the APA.
Why bother to take the test?
Intelligence tests are as much a measure of motivation as they are of mental ability, says research from the US. Researchers from Pennsylvania found that a high IQ score required both high intelligence and high motivation but a low IQ score could be the result of a lack of either factor.
So. The original study of 2012 went like this:
Recent reports show that fewer adolescents believe that regular cannabis use is harmful to health. Concomitantly, adolescents are initiating cannabis use at younger ages, and more adolescents are using cannabis on a daily basis. The purpose of the present study was to test the association between persistent cannabis use and neuropsychological decline and determine whether decline is concentrated among adolescent-onset cannabis users. Participants were members of the Dunedin Study, a prospective study of a birth cohort of 1,037 individuals followed from birth (1972/1973) to age 38 y. Cannabis use was ascertained in interviews at ages 18, 21, 26, 32, and 38 y. Neuropsychological testing was conducted at age 13 y, before initiation of cannabis use, and again at age 38 y, after a pattern of persistent cannabis use had developed. Persistent cannabis use was associated with neuropsychological decline broadly across domains of functioning, even after controlling for years of education. Informants also reported noticing more cognitive problems for persistent cannabis users. Impairment was concentrated among adolescent-onset cannabis users, with more persistent use associated with greater decline. Further, cessation of cannabis use did not fully restore neuropsychological functioning among adolescent-onset cannabis users. Findings are suggestive of a neurotoxic effect of cannabis on the adolescent brain and highlight the importance of prevention and policy efforts targeting adolescents.
The research was part funded by the National Institute on Drug Abuse. It did not take this into account:
The research, published in the journal Nature, shows that these changes in IQ are also linked with changes in brain structure.
To come to the conclusion, European researchers tested 33 teens in 2004 when they 12 to 16 years old. Then, the teens took the same tests four years later, when they were 15 to 20 years old. Brain scans were also conducted to examined their brain structure.
Researchers found that there was a difference in IQ scores between 2008 and 2004, with some people’s IQs improving by as many as 20 points, and others’ falling by the same amount. (The average score on an IQ test falls around 100, according toScience magazine.)
Not that any young teens looking to get goofed care about IQ tests. As the potheads say: “QUIZ?”