SOURCES

Fact 1

Brain Development

The teen brain shows greater ability to change (plasticity) than that of adults based on what teens do and experience. Using weed as a teen puts their brain development at risk.

A review of studies on how cannabis affects teens shows that THC can interfere with normal growth and brain development. Research over the years has found that using THC during adolescence can change the structure, molecules, and function of brain circuits.

Fact 2

Forming Memories

THC, the active chemical in weed, attaches to receptors in the hippocampus - the part of the brain responsible for processing information. It impairs the brain’s ability to form memories and may harm its development.

The hippocampus is the part of the brain that helps process information. THC can harm the hippocampus and another area called the ventromedial prefrontal cortex, which are both important for learning and memory. In a study on mice, researchers found that exposure to THC during adolescence caused long-term memory problems. Studies have also shown that THC use can impact short-term memory.

Fact 3

Connections in the Brain

Adolescence is an important period of brain development. Repeated use of cannabis during this period increases the risk of changes in the brain's structure, molecules, and connections.

‍Studies show that regular cannabis use can cause changes in the brain's structure, leading to poor neural efficiency. This means the brain's neurons don't communicate as well, which can result in slower thinking and make it harder to focus, learn, or remember things. It’s like having a weak Wi-Fi signal where the connection is slow and unreliable.

Fact 4

Weed Dependence

Individuals who use weed frequently to cope with their emotions are more likely to develop dependence and addiction. Frequent weed use can result in CB1 receptors in the brain becoming less sensitive to THC, which means you may need more to feel the same effects.

A study with weed users found that teens (12–17) who used weed without any previous dependency or addiction were more likely to develop a dependence on cannabis within 12 months, while young adults (18–25) were more likely to develop it within 36 months. According to the CDC, about 30% of cannabis users have cannabis use disorder, and the risk of developing it increases if teens begin using cannabis before age 18. A study found that using weed as a coping mechanism was a predictor of potential weed dependence.

Fact 5

Decision-Making

The prefrontal cortex is one of the last regions of the brain to mature. It is responsible for complex decision-making like planning, prioritizing, and controlling impulses. Using weed as a teen can increase the speed of cortex thinning, which can put brain development at risk.

‍Many studies have shown that not all regions of the brain develop at the same time. In fact, the prefrontal cortex, which is responsible for decision-making and impulse control, is one of the last regions of the brain to mature. In a study that compared the brains of weed and non-weed users, scientists found that marijuana use during adolescence can negatively impact the development of the prefrontal cortex and can increase the thinning of this region of the brain.

Fact 6

Brain Functions

The endocannabinoid system (ECS) helps regulate and create the balance of many body and brain functions. For many years, researchers studied what the ECS does. They have finally begun to understand the ECS’ role in regulating memory, coordination and alertness, coping with stress, and managing anxiety. But studies have shown that when THC enters the body, it overwhelms the ECS and prevents endocannabinoids from doing their job in regulating memory, coordination/alertness, coping with stress, and managing anxiety.

Fact 7

Coordination

Weed impacts the cerebellum, the part of the brain responsible for motor functions, and may harm its development.

Our motor functions are regulated by the cerebellum in our brains. One study on the effects of cannabis on adolescent brain development showed that chronic weed exposure can affect one's cognitive impairment. Cognitive impairment means having trouble with thinking, remembering, or concentrating. It makes it harder to focus, solve problems, learn new things, or remember information. It's like when your brain isn't working as clearly or quickly as it normally does.

‍Scientists compared the attention maturation of people who use weed with that of participants who had not used weed. People who used weed had "less age-expected improvements on tests assessing sustained attention, visuospatial working memory, and executive functioning" than nonusers. The cerebellum is responsible for these motor functions, and weed may harm its development as shown in this study.

Fact 8

Stress and Fear

Weed may affect the amygdala, the part of the brain involved in regulating stress and emotions, and may affect a person’s ability to process emotions.

Researchers have worked to understand what parts of the brain are affected by THC and have been able to identify potential physical and behavioral differences. This study identified the amygdala as one of the regions of the brain with the greatest relative differences in microstructure. The amygdala has also been identified as a key player in our emotional regulation. One study found that the amygdala volume of long-term heavy cannabis users showed a bilateral reduction in amygdala volume.

Fact 9

Reduced Motivation

Weed impacts the basal ganglia. That’s the part of the brain where you get motivation from. Regularly using weed can impact the production of dopamine. That’s the chemical in the body that allows you to feel pleasure, satisfaction, and motivation.‍

Research shows that cannabis exposure can impact specific neural circuits within the basal ganglia including circuits that manage motivation, learning, memory, and recognizing visual features. Chronic cannabis use can impact responses to internal and external motivation signals.