Participant Recruitment Now Underway for Landmark Study on Adolescents

Adolescence is a time of many physical, behavioral, and social transitions, not to mention changes in the brain. As part of their normal maturation, people in their second decade of life are beginning to become independent in the world, which means seeking new experiences and taking risks to determine what they are capable of. The state of the adolescent brain reflects this: The structure and circuits governing reward and emotion are more fully developed and tend to win out in the tug-of-war with the still-maturing prefrontal circuits governing judgment and impulse control. The behaviors that arise as a result of this imbalance can be wide-ranging, both positive and negative, including potentially harmful behaviors like substance use. Such behaviors can in turn affect how the brain develops, often in ways that remain poorly understood.

ABCD logo

The phrase “more longitudinal research needed” is the bottom-line message in many studies of substance use and other behaviors during this period of life and their long-term impacts—such as whether using drugs increases risk of mental illness (or vice versa), whether smoking marijuana causes lower IQ (or vice versa), or whether vaping leads to increased or decreased cigarette use. This is why we at NIDA are excited to announce that recruitment is now underway for the largest longitudinal study ever conducted on adolescent behavior, brain development, and related health outcomes.

The Adolescent Brain Cognitive Development (ABCD) study, which has been in the planning phase for just under a year, is now recruiting more than 10,000 9- and 10-year-olds at 19 research sites across the United States, and will follow these young people for a decade, through their early adulthood. Recruitment will be conducted over a two-year period through partnerships with public and private schools near the research sites, as well as through twin registries.

The study will collect an enormous amount of behavioral, genetic, and health data on the participants, including MRI scans every other year, so that brain development can be tracked and correlated with a vast range of factors including participation in extracurricular activities like music and athletics; video games and screen time; sleep habits; head injuries from sports; and experimentation with or regular use of alcohol, tobacco, marijuana or other substances, as well as socioeconomic and other environmental variables.

By collecting genetic information from all participants, we will gain insight into individual differences in brain development and the interaction of genes and environment in vulnerability to behavioral disorders and mental illnesses. Inclusion of a large twin cohort (800 twin pairs) will also give valuable insight into the role of genetics in determining behavioral and health outcomes.

Besides enabling researchers to draw stronger conclusions about the developmental impacts of adolescent behaviors and environments, it will also create, for the first time, a baseline standard of normative brain development. Today, when parents take their child to the doctor, their physical development can be plotted and compared to established norms for measures like height and weight, but nothing of this kind has ever existed for brain maturation. The ABCD study data will clarify the normal trajectory of brain development and its developmental benchmarks. At the end of this study, pediatricians will potentially have new brain-imaging biomarkers to determine if a patient’s development is off course, so that they can possibly intervene.

This study is only possible now, thanks not only to advances in neuroimaging and genetic analysis but also to the ability to manage and analyze the vast quantities of data that will be generated. The data gathered will be open access, available to other researchers to perform analyses that we cannot even at this point envision. Parents of 9- and 10-year-olds living near the 19 research sites the have a great opportunity to contribute to this major scientific undertaking, which will contribute greatly to our understanding of development during the second decade of life. ABCD has the potential to inform future educational strategies, prevention and other public health interventions, and science-based policy decisions, and thus NIDA and our partners across the NIH and in other government agencies are proud to be launching this study.  

For more information about ABCD, please visit its website at And for more information about how ABCD will contribute to the missions of our partnering NIH Institutes and other agencies, please visit the websites of: National Institute on Alcohol Abuse and Alcoholism, the National Cancer Institute, the Eunice Kennedy Shriver National Institute of Child Health and Human Development, the National Institute of Mental Health, the National Institute on Minority Health and Health Disparities, the National Institute of Neurological Disorders and Stroke, the NIH Office of Behavioral and Social Sciences Research, and the Division of Adolescent and School Health at the Centers for Disease Control and Prevention

Dr. Nora Volkow, Director

Here I highlight important work being done at NIDA and other news related to the science of drug use and addiction.

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 Adolescent Study

Cognition is also based on nutrition and you left that very important variable out of your study. Key macronutrients and micronutrients impact cognitive development eg Vitamin B12, DHA etc. I also believe cognition can be influenced by environment and the labeling on foods as a child can impact future behavior of a teen. I have spoken to you before about milk in California labeled White Gold and the potential to equate this comfort food named after marijuana with the comfort of marijuana. No food should be named after a drug. Of course branding could be a study itself but it could also be tied into your study.

Linda Griffith, PhD, RD

 Nutrition is indeed an

Nutrition is indeed an important factor in cognition and all aspects of adolescent development. Unfortunately, there are currently no well-validated measures available to study this that would not be burdensome to participants, so the difficult decision was made to not include nutrition yet. However, if and when well validated and easy-to-administer measures become available, nutrition may be added to the study protocol.

 Wonderful, but where is everybody? This is huge for science!

With the ABCD study we will have a lot more answers, and that is great!

I await anxiously to know whether or not mind-altering recreational drugs, specifically marijuana, can actually alter minds. Can cannabis and other drugs induce psychosis, or are society’s sociopaths merely attracted to drugs for whatever reason? Such a simple, yet ever so elusive proposition.

I am not sure who is noticing, or whatever interest there is from NIDA, academia or whomever, but it appears that a remarkably high percentage of today’s sociopaths are using drugs. Can it be that the modern rise in rampage killings is simply a normal aspect of a highly complex and stressful society regardless of drug abuse- i.e. correlation, but no causation? Or is the increase in these senseless outbreaks of violence a relatively new phenomenon because some otherwise healthy individuals induce or exacerbate their own mental derangement from drug abuse?

These are big questions because currently there is a concerted, national effort to push marijuana legalization and acceptance. Over the next ten years, marijuana usage will certainly expand among all age groups, plus the drug will continue to gain in potency. If the causal link between marijuana and psychosis can be positively validated by the ABCD project, we may unfortunately see many more cases of schizophrenia associated with violence that could have been avoided.