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Smoking marijuana reduces intelligence
Last reviewed: 01.07.2025
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Unfortunately, in the modern world, drug addiction among teenagers is a widespread phenomenon. Disappointing world statistics say that it is people who have not reached adulthood who are the biggest lovers of marijuana.
Smoking marijuana temporarily alters mood, thoughts, feelings, and perceptions. In most cases, users of the drug perceive these changes as positive.
Systematic use of marijuana by teenagers under 18 years of age threatens memory and cognitive impairment. Such conclusions were reached by an international research group.
“Our goal was to find out what changes occur in the brain of adolescents who use marijuana, as well as what consequences regular cannabis smoking has,” says Dr. Madeline Mayer, the initiator of the study, a PhD candidate at Duke University.
The experts conducted long-term studies and analyzed the intelligence level of 1,000 New Zealand residents whose cannabis use began in adolescence and continued to the present day. All 37-38 year old study participants passed a series of psychological tests on the speed of information processing, visual perception and memory.
When experts compared the results of adolescent tests and their current indicators, it was found that, on average, the level of intellectual development of people who have smoked marijuana for a long time decreased by an average of eight points.
According to Madeline Mayer, unfortunately, these processes are irreversible.
An analysis of cognitive abilities and intellectual activity of people who began using marijuana as adults with a fully formed organism did not show such results. Their health was not so devastatingly affected.
So-called "early" smokers experience a steady decline in memory, language skills, comprehension, perception and planning skills.
Experiments on animals using cocaine, alcohol and nicotine show that systematic use of drugs and alcohol leads to irreversible processes in the brain.
"This is especially true during puberty, when teenagers are at a time of heightened vulnerability. The role of dosage in these processes is also unknown," says Lawrence Steinberg, a psychologist at Temple University.
Research by scientists points to the obvious harmful effects of marijuana on the adolescent body. Drug use causes more serious brain damage during puberty than in adulthood.
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