Employees at the University of Colorado at Boulder have debunked the myth that cannabis reduces IQ. According to scientists, smoking marijuana does not affect the intellectual abilities of a person.
The first study on the effects of cannabis use
In 2012, a group of American scientists published the results of a study on the effects of marijuana on human cognitive abilities. The trials were attended by volunteers aged 13 to 38 years. They passed an interview, and also passed tests that determine the level of IQ and the ability to make decisions. As a result, it was found that people who began to smoke marijuana as a teenager are inferior in cognitive performance to their peers who have never used cannabis. At the same time, the dosage and duration of cannabinoid intake directly affected the degree of degradation of intellectual functions.
The authors concluded that hemp has a neurotoxic effect, which in turn leads to a reduction in IQ if a person consumes cannabis before the age of 18. The doctors subsequently drew a verdict based on the results of this study: “Smoking marijuana reduces cognitive function, especially among teenagers.”
Cannabis does not reduce cognitive abilities
To confirm or refute the theory of the harmful effects of cannabis on intelligence, specialists from the University of Colorado at Boulder carried out their research program, in which 428 twin pairs took part. Scientists conducted IQ tests and compared the scores of the twins who smoked marijuana with those of their siblings. Based on the hypothesis put forward in 2012, experts suggested that twins who do not use cannabis will gain more points. However, in practice, this did not happen: the authors of the project did not record a significant difference in the level of intelligence of volunteers.
Test Manager Megan Ross believes that in 2012, her colleagues did not take into account secondary factors related to the environment and the genetics of the volunteers. That is why they made the wrong conclusion that hemp negatively affects cognitive function. Ross claims that the results of their research most accurately reflect the real state of things, as university employees evaluated volunteers several times (in adolescence and youth, as well as before starting marijuana smoking), using methods to determine the following characteristics:
- level of intelligence;
- ability to make decisions;
- speed and intensity of the reaction to irritating factors;
- RAM size.
None of the above indicators have decreased due to cannabinoids. Therefore, the assertion that hemp makes a person dumber is not scientifically sound. However, the project contains one drawback – a small number of volunteers abusing cannabis took part in it. In this regard, scientists want to repeat the experiment, only this time attract more people who smoke high-dose marijuana.