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How Marijuana Affects the Teenage Brain

Understanding the Long-Term Impact of Cannabis on Teens

According to nationwide survey findings by the Substance Abuse and Mental Health Agency in 2018, marijuana is the most frequently used drug in the US. The findings report found that 43.5 million admitted to using it within a year of the survey. Teens make up an alarming share of that statistic. The agency discovered that one in eight (approximately 3.1 million) adolescents between the ages of 12 and 17 had smoked pot at least once in the past year. Between the ages of 18 and 25, that number increased to one in three (or 11.8 million). This is three times as much THC as high schoolers were smoking 30 years ago.

Despite the full legalization of recreational marijuana in certain states, scholars recognize it as a gateway drug — its use potentially leads to the consumption of other more dangerous substances. This makes marijuana a harmful substance for teens, and its use is cause for concern.

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What Are THC and What Are Its Effects?

How does marijuana work at a chemical level? THC is the acronym for tetrahydrocannabinol, the active chemical in marijuana. Its structure is very similar to anandamide, a chemical that naturally exists in the brain. Structural similarity between the two chemicals causes the body to accept THC and alter the communication of chemical signals within the nervous system.

According to the National Institute on Drug Abuse, THC can attach itself to cannabinoid receptors and activate neurons to disrupt both mental and physical functions, such as memory, thinking, concentration, movement, coordination, and pleasure. This is why it is dangerous for someone under the influence of marijuana to attempt driving. The brain’s reward center is stimulated by the drug use by the release of dopamine, which is why its use causes people to seek sex and food.

These effects prove immensely problematic for immature and underdeveloped brains in their formative years. Unfortunately, marijuana does more to the brain than produce the high that users seek.

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Scientific Research on the Effect of Marijuana on Teen Brains

Scientific research has found that the human brain isn’t fully developed until a human reaches their mid-20s, which means that, until then, perfect judgment isn’t a teenager’s strong suit. The rational part of a young person’s brain is not completely formed until around age 25, making adolescents especially susceptible and sensitive to drug exposure.

In truth, for an adult, an occasional joint probably won’t be disastrous. However, for a teenager, repeated use can set the stage for lifelong mental and physical health challenges. Here are some short-and long-term effects a teen could potentially experience from the regular use of recreational marijuana.

1. Marijuana impacts the structure and function of a teen’s brain.

THC interferes with neurotransmitters in a developing brain, literally changing the physical structure of the brain and impairing the parts that govern focus, coordination, decision-making, emotions, learning, memory, and reaction time. As a direct result, studies have shown that marijuana use is positively correlated with low cognitive function in adolescents — lower than in teens abusing alcohol — and problems can become even worse.

Research has found that problems with underage marijuana use extend beyond neurocognitive disadvantages. In 2014, a study found that THC in a teen brain can cause macrostructural brain alterations leading to gray tissue matter damage where the majority of neurons reside. The grey matter houses the parts of the brain that control muscle movement, memory, several of the senses, decision making, speech, emotion, and more. Once this region is damaged, the cells die because they can’t properly communicate, leading to irreversible brain damage.

2. Heavy marijuana use can lower a growing human being’s IQ

Many of today’s individuals classified as intelligent have a background of underage marijuana use, but this doesn’t mean they weren’t affected. A scientific study conducted in Dunedin, New Zealand, revealed evidence on this matter.

The study focused on 1,037 people born between 1972 and 1973 and followed them into their early 40s. The researchers learned that subjects who began smoking pot frequently early on in life lost up to six points of their IQ by the time they were 38. Unfortunately, at the age of 38, this group of subjects had an IQ that was lower than 70% of their peers.

Researchers later decided to follow up with the participants of the Dunedin study, and they found that these people had not been able to regain the IQ points they’d lost, suggesting that the changes to their abilities may be permanent.

3. Daily smokers of pot are less likely to graduate from high school.

The Lancet Psychiatry, a weekly peer-reviewed general medical journal, published statistics gathered by researchers in Australia and New Zealand that suggest teenagers who smoke weed daily are 60% less likely to graduate from high school than non-smokers. As of 2013, the US Bureau of Labor Statistics said that only 27% of employers hire candidates without a high school diploma, underscoring that graduating from high school matters. While teens who smoke marijuana every day may have secondary problems at play, such as teacher or family relationships, this data nonetheless warrants concern.

A 2011 study on factors underlying dropout rates in pot-using teens showed that dropping out before graduation was not necessarily correlated with cognitive impairment, as you might expect. Rather, it was the social circumstances surrounding recreational marijuana use that determined whether the student graduated or not — such as an association with deviant peers opposing traditional values or the child’s perception of their parents’ attitude toward marijuana.

4. Smoking pot regularly can cause schizophrenia.

The National Academies of Science, Engineering, and Medicine reported in January of 2017 that youths who smoked marijuana had a high risk of schizophrenia. The Dunedin article referred to above confirmed this in its findings, reporting that pot-smoking teens were not merely “a little” more susceptible to schizophrenia — they were twice as susceptible.

The National Institute on Drug Abuse’s article on the link between marijuana use and psychiatric disorders claims that marijuana increases the risk of developing schizophrenia and other disorders by five times than people who have never used it. The reason, they say, could be that some individuals have a genetic vulnerability to the condition, and the use of marijuana activates the gene. The Centers for Disease Control and Prevention have also said that, for youth with a family history of schizophrenia, marijuana use can further this risk.

Harvard Health says that another possible reason could be the simple fact that THC overstimulates the brain and instigates reactions contributing to the psychological and physical effects of the drug. Science is still unclear about how this works, but what is determined, according to the article, is that using marijuana before the mid-20s thwarts brain development and increases an adolescent’s risk of psychosis.

5. Teens dependent on regular pot smoking are more likely to commit suicide.

Perhaps the most devastating correlation researchers have made between underage marijuana use and teen suicide. The National Drug and Alcohol Research Centre at Australia’s University of New South Wales conducted research that showed young people who started smoking marijuana daily before age 17 were seven times more likely to commit suicide than young people who did not smoke marijuana regularly.

This fits with the widespread belief that early use of marijuana is positively correlated with serious mental health conditions later in life, such as severe depression, anxiety, psychotic disorders, and addiction — all of which can lead to suicidal thoughts. Today, suicide is in the top five leading causes of death in teens. Beachway fights hard to make sure this unacceptable statistic never becomes a new norm.

All of this research combined determines that cannabis use is a major problem that warrants attention.

6. Pot-smoking teenagers are likely to exhibit antisocial behavior.

According to the Centers for Disease Control and Prevention, teenagers who regularly smoke marijuana may avoid sporting events, social activities, and even family get-togethers in favor of smoking pot. In fact, the National Institute on Drug Abuse for Teens says that one in six adolescents who regularly use marijuana will become addicted to the drug and will withdraw from social activities as a result.

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Learn How to Help Your Struggling Teen

As local laws regarding marijuana use continue to relax, society’s youth will have easier access to this substance. That’s why it’s more important than ever to know the signs that your child is hiding a drug problem from you and to understand the risks of underage substance abuse.

Beachway understands that reading about the effects of marijuana on the growing human brain can be discouraging, particularly for parents of youths using the drug. But as you continue to learn more about marijuana and how it affects your child, you can develop all the skills you need to confront this issue in a positive, helpful way. At Beachway Therapy Center, our drug rehabilitation specialists can teach you these skills quickly and effectively.