Imaging studies of marijuana's impact on brain structure in humans have shown with lower scores on a test of verbal memory but did not affect other cognitive abilities The study will use neuroimaging and other advanced tools to clarify. A study found differences in the brains of users and nonusers, but it did not establish that marijuana use caused the variations or that they had. There are a number of shocking ways weed can affect you and your brain, and these changes might not be side effects you have heard before.
Your Brain? Will THC Harm
Clinical research has not yet confirmed that marijuana use can have permanent effects on brain function. So far, the effects of the drug have been linked primarily to long-term use and appear to be reversible. If you stop abusing marijuana, its effects on your memory, learning and coordination may disappear. A study published in a issue of Psychopharmacology tested a group of adolescents between the ages of 16 and 20 on their learning and memory skills.
Out of this group, cannabis users scored lower on cognitive tests than alcohol users or non-drug users. The younger the teens were when they started to use marijuana, the more severely their learning and memory were affected. The results of this study indicate that marijuana may have a more serious impact on the adolescent brain than on adult cognition.
Substantial evidence from animal research and a growing number of studies in humans indicate that marijuana exposure during development can cause long-term or possibly permanent adverse changes in the brain. Rats exposed to THC before birth, soon after birth, or during adolescence show notable problems with specific learning and memory tasks later in life. Some studies suggest regular marijuana use in adolescence is associated with altered connectivity and reduced volume of specific brain regions involved in a broad range of executive functions such as memory, learning, and impulse control compared to people who do not use.
Among nearly 4, young adults in the Coronary Artery Risk Development in Young Adults study tracked over a year period until mid-adulthood, cumulative lifetime exposure to marijuana was associated with lower scores on a test of verbal memory but did not affect other cognitive abilities such as processing speed or executive function.
The effect was sizeable and significant even after eliminating those involved with current use and after adjusting for confounding factors such as demographic factors, other drug and alcohol use, and other psychiatric conditions such as depression.
A large longitudinal study in New Zealand found that persistent marijuana use disorder with frequent use starting in adolescence was associated with a loss of an average of 6 or up to 8 IQ points measured in mid-adulthood. People who only began using marijuana heavily in adulthood did not lose IQ points. These results suggest that marijuana has its strongest long-term impact on young people whose brains are still busy building new connections and maturing in other ways.
The endocannabinoid system is known to play an important role in the proper formation of synapses the connections between neurons during early brain development, and a similar role has been proposed for the refinement of neural connections during adolescence. If the long-term effects of marijuana use on cognitive functioning or IQ are upheld by future research, this may be one avenue by which marijuana use during adolescence produces its long-term effects.
However, recent results from two prospective longitudinal twin studies did not support a causal relationship between marijuana use and IQ loss. However, at the start of the study, those who would use in the future already had lower scores on these measures than those who would not use in the future, and no predictable difference was found between twins when one used marijuana and one did not.
This suggests that observed IQ declines, at least across adolescence, may be caused by shared familial factors e. Over the next decade, the National Institutes of Health is funding the Adolescent Brain Cognitive Development ABCD study —a major longitudinal study that will track a large sample of young Americans from late childhood before first use of drugs to early adulthood.
The study will use neuroimaging and other advanced tools to clarify precisely how and to what extent marijuana and other substances, alone and in combination, affect adolescent brain development. Regular pot smokers are more likely to have persistent coughs, have some trouble breathing, and produce excess phlegm and mucus from their throats.
Out of the respiratory system, THC the active compound in cannabis exits the lungs and enters the bloodstream, where it moves throughout the body. The National Institute on Drug Abuse cautions that the chemical can increase the heart rate by as many as 50 beats per minute, which can last as long as three hours.
Smokers who have heart disease could be at a greater risk of heart attack. Research from the Journal of the American Heart Association suggests that regular marijuana use can not only contribute to the possibility of a heart attack, but also to heart rhythm disorders and stroke , even in young people who have no other risk factors for heart disease.
The point is echoed by the American College of Cardiology , which notes that marijuana causes irregular heart rates and increases the risk of an acute coronary syndrome, which refers to any number of conditions that can be brought on by the sudden interruption of the blood flow to the heart. As a result of this, users who are susceptible to conditions of the heart are taking a serious risk when they smoke marijuana.
One of the more distressing risks of long-term effects of marijuana consumption is found in women who are pregnant. Marijuana has a complicated relationship with sexual libido and function. However, animal studies have found that marijuana inhibits the receptors in the erectile tissue of the animal penis, according to a study in the Journal of Sexual Medicine , suggesting that cannabis consumption before sex does more to limit sexual function than it does to help it.
Even as some research has suggested that long-term marijuana use carries a minimal risk of physical consequences, such as that published in JAMA , scientists still urge caution. The sentiment is shared by some smokers themselves. Writing in Vice magazine, one user noted that most of the heavy smokers he knows get high on a regular basis without the stereotypical feelings of laziness or paranoia.
Some went so far as to note that long-term weed use even changed their personalities, making them less outgoing and socially engaged. One negative effect the JAMA scientists noticed was that people who smoked pot for a long time tended to have worse periodontal gum health than others, which in some cases led to the development of gum disease.
Aside from effects on the brain and body, what else can the long-term consumption of marijuana do?
What Happens Inside Your Brain When You Smoke Weed?
Governments and communities worldwide are softening their views on cannabis use. Trials of medicinal cannabis have been approved in Victoria, Queensland. What Marijuana Does to Our Brains in the First Couple of Hours Like alcohol, caffeine, and sugar, cannabinoids also affect the levels of. What researchers do not fully understand is what effect that marijuana can have on the brain when someone uses the drug regularly over a.