In the United States, marijuana is the most commonly used drug among teens and young adults. Use of the drug continues to skyrocket among this age group.
However, many parents appear to be relatively unconcerned and fail to address the dangers of marijuana use with their offspring. This is especially true for parents who used less potent forms of the drug that were available in their youth.
Although the drug is legal in several states, addiction professionals know that marijuana is not a risk-free substance for young users. In fact, numerous studies have indicated that chronic marijuana use in teens may have a marked affect on memory. Effects on the teen brain are especially notable in heavy users who started smoking marijuana before they turned 16, and who use the drug daily for at least three years.
Once people reach their mid-twenties, the damage isn’t as apparent. What accounts for the difference? The human brain is still under construction until the early or mid-20s, which means that certain important areas aren’t fully developed and are highly vulnerable to damage.
One study conducted by Chicago’s Northwestern University Feinburg School of Medicine asked heavy marijuana users to listen to a short story, and then recall the details of the story 20 to 30 minutes later. Test scores of teens who used marijuana regularly were 18 percent lower than test scores of teens who didn’t use the drug. The scores continued to be lower after the teens reached their early 20s and hadn’t used the drug for two years or more.
Researchers at Northwestern University also found that the teens who used marijuana displayed physical changes in the hippocampus – an area of the brain associated with long-term memory. They determined that the heavier the use, the more abnormal the shape of the hippocampus and the more severe the effect on concentration and the ability to learn new things.