Teen Brain Development and Alcohol

Teen brain development and alcohol – believe it or not – alcohol does not work the same way in the teen brain as it does in the brain of an adult. Why?

A picture is worth a thousand words, and I thought the following images may help readers better understand the impact of alcohol (or any substance) on the developing brain.

Teen Brain Development and Alcohol

As I’ve stated in other posts and in my book (If You Loved Me, You’d Stop!…), new brain imaging technologies (MRI, PET, SPECT) of the past 15 years, or so, now allow scientists to study the live, human brain, and with that, they now understand that alcoholism is a disease of addiction (which is a chronic, relapsing brain disease), and that alcohol affects the teen brain differently because of the critical brain development occurring from ages 12 through 20, often until age 25.

The image above(1) is a time-lapse of brain imaging studies that shows how the brain develops from age 5 through 20 and beyond. It was thought (until these new brain imaging capabilities) that the brain was fully developed by adolescence. We now know it’s not. There is a critical developmental stage identified as pruning and strengthening that goes on during the teen years and on into college and even beyond. Pruning is when neural connections (called gray matter) that are not used fall away (get “pruned”), and those that are used get strengthened, which makes the remaining neural connections more efficient (like an insulted cable wire vs a non-insulated one). [Source: Partnership for a Drug Free America, “A Parent’s Guide to the Teen Brain.”]

As you can see when looking at the image above, the brain develops from back to front. This means that the portions of the brain that deal with emotion, memory, learning, motivation and judgment are the last to develop and, as such, are the most deeply affected by alcohol (or drug abuse) during ages 12 through 20, often through age 25. For example, if a teen abuses alcohol, the neural connections associated with memories and experiences related to alcohol abuse are the ones that are strengthened and thus embedded. By the same token, neural connections damaged by or not used because of alcohol abuse (those related to learning or judgment, for example) are pruned or not strengthened. [This late stage brain development also explains why teens don’t know why they do some of the things they do, and why they take risks they likely would not engage in if they had a fully developed brain and the hindsight (memories and experiences) that go with it.]

This image(2) gives you a visual of what Teen Brain Development and Alcoholhappens to the developing brain when heavy drinking is introduced.  You may want to visit: Amen Clinics SPECT Gallery Images of Alcohol and Drug Abuse to see additional brain images showing the effects of various types of drug use (alcohol, meth, cocaine, marijuana).

For now, I’ll leave you with one more thought. Age of first use, independent of other factors (e.g., genetics, environment, mental health issues [ADHD, depression, bi-polar, PTSD]), strongly predicts the development of a lifelong addiction to alcohol.(3) Children who begin drinking before the age of 15 are five times more likely to develop problems with alcohol than those who start after 21.(4) For each year a teen delays alcohol use, their chances of becoming dependent (addicted to alcohol) drops by 14%.(5) The National Institute on Alcohol Abuse and Alcoholism (NIAAA) reports that one-half of alcoholics were addicted by age 21, and 2/3 were addicted by age 25.(6) [Typically, only 10% eventually get help, and those that do, typically don’t seek help for another 10 – 20 years, which is why we’ve always assumed alcoholism (an addiction to alcohol) was an adult disease and treated underage drinking as something most kids do but nothing to worry about.] For more on risk factors for developing alcoholism, as well as information on the disease of addiction, of which alcoholism is one, visit the links in this sentence.

There is much we need to do to share and take advantage of this new research (which I’ll save for another post), but before I close, I want to mention that the Europeans are not any better off – they have not successfully taught their children how to drink. In January 2009, Sir Liam Donaldson, the Chief Medical Officer of Great Britain, issued the first ever parental guidelines with regards to underage drinking, which advise parents that children under the age of 15 must not be allowed to drink. One reason: their government research shows that more than half of 15 and 16-year-olds (56%) have drunk heavily in the last month. [Click here for source article.] As for the French — they consider alcohol abuse and alcoholism a critical health issue for their country, similar to the way we once viewed smoking, causing us to ban smoking in all public places, for example. Click here to read a post on this topic.

Before I sign off on this post, please know that the BRAIN CAN CHANGE if alcohol (or drug) abuse is stopped. So even though these images look daunting — the brain can change (and there are suggestions for how to help this change be most effective) and a person can go back to “normal” — that’s something else we didn’t know until these advances in brain imaging technologies.

Please pass this along. The more we start to understand all of this, the better we will be able to help our children.


(1) Thompson, Paul. Ph.D., Time-Lapse Imaging Tracks Brain Developing from ages 5 to 20, UCLA Lab of Neuro-Imaging and Brain Mapping Division, Dept. Neurology and Brain Research Institute, http://www.loni.ucla.edu/~thompson/DEVEL/PR.html

(2) Tapert, Susan, Ph.D., Image of 15-year-old NON-drinker on top and 15-year-old heavy drinker on bottom — lack of pink and red coloring denotes poor brain activity during memory task, Department of Psychiatry, University of California, San Diego.

(3) NIAAA Statistical Snapshot Underage Drinking, http://www.niaaa.nih.gov/AboutNIAAA/NIAAASponsoredPrograms/StatisticalSnapshotUnderageDrinking.htm

(4) The National Survey on Drug Use and Health Report, 10/22/04

(5) Spear, L.P., The Adolescent Brain and Age-Related Behavioral Manifestations, Neuroscience and Biobehavioral Reiews 24 (2000) 417-463

(6) NIAAA Statistical Snapshot Underage Drinking, http://www.niaaa.nih.gov/AboutNIAAA/NIAAASponsoredPrograms/StatisticalSnapshotUnderageDrinking.htm



Lisa Frederiksen

Lisa Frederiksen

Author | Speaker | Consultant | Founder at BreakingTheCycles.com
Lisa is the author of hundreds of articles and 11 books, including "If You Loved Me, You'd Stop!," "Addiction Recovery: What Helps, What Doesn't," and "Secondhand Drinking: the Phenomenon That Affects Millions." She is a national keynote speaker with over 25 years speaking experience, consultant, and founder of BreakingTheCycles.com. She has spent more than 14 years studying 21st century brain research in order to write, speak, and consult on substance use disorders prevention, intervention and treatment; mental disorders; addiction (aka substance use disorders) as a brain disease; adolescent addiction treatment vs adult addiction treatment; effective treatment for co-occurring disorders (having both a substance use and mental disorder); secondhand drinking | drugging; help for the family; and related subjects. In 2015, she founded SHD Prevention, providing training and consulting to companies, public agencies, unions, nonprofits and other entities to address the workplace impacts of employee secondhand drinking and alcohol misuse.

12 Responses to Teen Brain Development and Alcohol

  1. Adi Jaffe says:

    Great post Lisa,
    It’s not often that people outside of those studying neuroscience think this deeply about the crucial periods of brain development.

    It’s great to see this information passed along somewhere outside of our site. I hope that your readers take careful note of the details in your post.

    Good work!

  2. […] understand how the brain develops from ages 12 – 25 – addiction is a young person’s disease, but it often takes until they are much older before it’s diagnosed and hopefully treated – click here for an earlier post, “Teen Brain Development and Alcohol” […]

  3. […] 14-20 is ADHD Awareness Week. Mental illness and age of 1st use of alcohol (or other drugs) are two of the key risk factors contributing to a person’s development of alcohol abuse […]

  4. Trevor_Memory says:

    Great post! It is definitely true that alcoholic drinkers don’t develop the right brain process. One of the reasons is that they can’t focus and concentrate on what they were doing or on what they should be doing.

  5. LisaF says:

    Thanks so much for your comment!

  6. Deb Harig says:

    I work in substance abuse prevention and often do presentations to parents. This information and the brain images are very powerful, but I am not clear on what you mean by the statement “…if a teen abuses alcohol, the neural connections associated with memories and experiences related to alcohol abuse are the ones that are strengthened and thus embedded.”. Does this mean that the young person is more likely then to repeat this behavior? I would like to be able to explain this image and this information more clearly.
    Thank you!

  7. Hi Deb,
    Yes, you are correct.
    This post, The Brain and the First Years of Life, http://www.breakingthecycles.com/blog/2010/03/09/the-brain-and-the-first-years-of-life/
    explains how neural networks develop in early childhood — a process that continues until one’s early to mid-twenties and continues for the rest of our lives.
    Thanks for reading.

  8. Faculty of sciences » Blog Archive » Teens and Alcohol says:

    […] 3.       Look at an illustration about alcohol’s effect to brain […]

  9. […] by excessive amounts of alcohol, which would be considered more than 3 drinks in a sitting: Teen Brain Development and Alcohol | BreakingTheCycles.comBreakingTheCycles.com In the link above, please check out the images of a drinking vs. non-drinking teen showing memory […]

  10. […] Teen Brain Development and Alcohol from breakingthecycles.com […]

  11. Jackie Bell says:

    I found this article researching on how alcohol can affect the brain in general, and let me tell you, this was a huge help and actually kind of a wake up call. I’ve never been strictly against younger people drinking (of course, not too young), but possibly older teenagers and early 20 somethings… but this has completely changed my mind. I’m so glad I found this! Thank you so much for the research and spreading knowledge that will help motivate others to keep their brains healthy.

    I’m writing this down to remind me:

    “… alcohol affects the teen brain differently because of the critical brain development occurring from ages 12 through 20.”

    Thanks again!


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