Adolescent Brain Cognitive Development Study (ABCD Study®)

Landmark study of adolescent brain development renews for additional seven years

ABCD logo - brains at various levels of development according to age
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ChildArt ABCD Study
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With nearly $290M of new funding for seven years to research institutions around the country, the National Institutes of Health renewed its commitment to the Adolescent Brain Cognitive Development (ABCD) Study, the largest long-term study of brain development and child health ever conducted in the United States.

“The next phase of the ABCD study will help us understand the effects of substance use, as well as environmental, social, genetic, and other biological factors on the developing adolescent brain,” said NIDA Director Nora D. Volkow, M.D. “Since the participants are now in their vulnerable middle school years or are beginning high school, this is a critical time to learn more about what enhances or disrupts a young person’s life trajectory.” Read the Press Release.

Illustration of adolescents

Podcast: With Neuroimaging, Large NIH Study Could Shine a Light on the Adolescent Brain

JAMA, August 14, 2019: Audio 25 min 18 sec

In this Medical News podcast, Jennifer Abbasi interviews the director of the ABCD study, Gaya Dowling, PhD, about this long-term study of brain development and child health in the United States.

Combining results from 628 children's brains, this MRI scan shows regions activated as faces are viewed (yellow and orange) and other areas (blue and cyan) activated during a demanding working memory task. 

Science Magazine, January 3, 2018 Huge study of teen brains could reveal roots of mental illness, impacts of drug abuse

CBS - 60 Minutes, December 9th, 2018

Image of researchers looking at a brain scan on a computer
60 Minutes goes inside a landmark government study of young minds to see if phones, tablets and other screens are impacting adolescent brain development.

Please note: The ABCD study is assessing brain development in children throughout adolescence, while tracking social, behavioral, physical and environmental factors that may affect brain development and other health outcomes. Screen time is only one of many measures evaluated as part of the study protocol.


Annual Curated Data Release

On April 2, 2019, The National Institutes of Health released to the scientific community the comprehensive baseline dataset from the Adolescent Brain Cognitive Development (ABCD) study. Enrollment is complete with a total of 11,878 youth and their families participating in the study, including about 2,100 young people who are twins or triplets.

Approximately 100 terabytes of data obtained from the full participant cohort are available to scientists worldwide to conduct research on the many factors that influence brain, cognitive, social, and emotional development. The ABCD study is the largest long-term study of brain development and child health in the United States. 

  • Data Release 2.0, available now on the NIMH Data Archive, includes baseline data on the full participant cohort, ages 9-10 years. Last year’s release (Data Release 1.1) contained baseline data on nearly half of the cohort.
  • This release includes much of the same type of data as contained in Data Release 1.1, but also includes genotypic data for the first time:
    • Genomics data (Smokescreen genotyping array) are available on almost 11,000 participants. These include common variations, as well as variations associated with addiction, smoking behavior and nicotine metabolism.
  • A Data Exploration and Analysis Portal (DEAP) is available on the NIMH Data Archive to facilitate analysis of ABCD Study data. The DEAP allows authorized users to analyze ABCD Study data online, while providing appropriate statistical models and tools that take advantage of the study design.
  • Participants will be followed for 10 years, during which data are collected on a semi-annual and annual basis through interviews and behavioral testing. Neuroimaging data, including high resolution MRI, are collected every two years to measure changes in brain structure and function.
  • Data will be released annually. The next data release will be in early summer 2020 and will include the first longitudinal data from the 6-month and 1-year follow-up assessments.
  • For more information about Data Release 2.0 and to request access to the data, visit the ABCD data collection on the NIMH Data Archive.

Study Enrollment Completed

ABCD Study Enrollment has completed as of 10/21/18 - the total enrollment stands at 11,875.

Enrollment completed as of 10/21/18.  Total 11,874 participants

What Is the Adolescent Brain Cognitive Development (ABCD) Study?

ABCD is a landmark study on brain development and child health supported by the National Institutes of Health (NIH). This project will increase our understanding of environmental, social, genetic, and other biological factors that affect brain and cognitive development and that can enhance or disrupt a young person’s life trajectory.

For an overview of how the ABCD study got started, see article co-authored by NIDA Director Dr. Nora Volkow, NIAAA Director Dr. George Koob, NINDS Director Dr. Walter Koroshetz, and other NIH scientists: The conception of the ABCD study: From substance use to a broad NIH collaboration, published in Developmental Cognitive Neuroscience. 

How Will the ABCD Study Be Implemented?

Unique in its scope and duration, the ABCD study will:

  • Recruit 11,900 healthy children, ages 9 to 10 across the United States, with the goal of retaining 10,000 into early adulthood.
  • Use advanced brain imaging to observe brain growth with unprecedented precision.
  • Examine how biology and environment interact and relate to developmental outcomes such as physical health, mental health, and life achievements including academic success.

Why Do We Need the ABCD Study?

Adolescence is a period of dramatic brain development in which children are exposed to all sorts of experiences. Yet, our understanding of precisely how these experiences interact with each other and a child’s biology to affect brain development and, ultimately, social, behavioral, health, and other outcomes, is still incomplete. As the only study of its kind, the ABCD study will yield critical insights into the foundational aspects of adolescence that shape a person’s future.

What Will We Learn from the ABCD Study?

The size and scope of the study will allow scientists to:

  • Identify individual developmental trajectories (e.g., brain, cognitive, emotional, academic) and the factors that can affect them.
  • Understand the role of genetic vs. environmental factors on development.
  • Examine the effects of physical activity, screen time, and sleep, as well as sports and other injuries, on brain development and other outcomes.
  • Study the onset and progression of mental disorders.
  • Determine how exposure to substances (e.g., alcohol, marijuana, nicotine, caffeine) and new ways of taking them (e.g., vaping, dabbing) affect developmental outcomes and vice versa.
  • Understand the impact of changing state and local policies and laws (e.g., marijuana, tobacco, alcohol) on youth drug use and related health and development.

Scientific publications authored by ABCD Study investigators, collaborators, and other researchers can be found at

Who Is Leading the ABCD Study?

The ABCD study is led by the Collaborative Research on Addiction at NIH (CRAN):

  • National Institute on Drug Abuse (NIDA)
  • National Institute on Alcohol Abuse and Alcoholism (NIAAA)
  • National Cancer Institute (NCI)

In partnership with:

  • Centers for Disease Control and Prevention (CDC)
  • Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
  • National Institute of Mental Health (NIMH)
  • National Institute of Minority Health and Health Disparities (NIMHD)
  • National Institute of Neurological Disorders and Stroke (NINDS)
  • NIH Office of Behavioral and Social Sciences Research (OBSSR)
  • NIH Office of Research on Women’s Health (ORWH)

For additional information on ABCD, please contact:
Dr. Gaya Dowling, Director, ABCD Project at 301-443-4877 or at or visit

For more information for researchers, visit:

Download: Flyer on the ABCD Study (PDF, 2.7MB)