Researchers Speak: The ABCD Study

In this video, Dr. Terry Jernigan, Professor at the University of California, San Diego and the Co-Director of the Coordinating Center for the ABCD Study, describes the purpose and goals of the Adolescent Brain and Cognitive Development (ABCD) Study.

Hello, I’m Terry Jernigan, Professor at the University of California, San Diego and the Co-Director of the Coordinating Center for the ABCD Study. I’m trained as a cognitive neuroscientist and clinical psychologist, and for the past decade my primary research interest has been the developing human brain and the emergence of individual differences in cognitive and emotional traits. 

ABCD is the Adolescent Brain and Cognitive Development Study, a large-scale, long-term study of children and adolescents, conducted by investigators throughout the United States. Over 10,000 children will be studied with comprehensive assessments of health and mental health, neurocognition, culture and environment, activities and habits, and a sophisticated neuroimaging protocol to assess the biological and functional development of the brain. The children will be enrolled at 9 or 10 years of age, and we hope to follow them for 10 years into young adulthood.  

Our goal is to ensure that in every way possible this large group of children will have diverse backgrounds that closely mirror those of the entire population of children of this age in the United States. To have a chance of reaching every child in every community surrounding our 19 sites, we will work primarily with schools to contact families with eligible children, though we will use other methods to contact families in some cases. 

Adolescence is a highly dynamic period of human development that begins in late childhood and proceeds through puberty and adolescence to early adulthood. Only recently have we come to appreciate that the rapid changes in behavior during this period are accompanied by equally dynamic neurobiological development. Adolescence an important, and often pivotal, time in the lives of young people. For many it’s a time of dramatically increasing knowledge and skill—a time when youth find their intellectual and creative voices, if you will, and form strong bonds with friends and family. In other words, many young people emerge from adolescence engaged, independent, and resilient to life’s challenges.  

Unfortunately, though, this is also a period during which the first signs and symptoms of some serious problems appear, such as depression, anxiety, and psychosis—and some youth become disengaged, academically and socially. And although it is typical, and healthy, for adolescents to begin to take more risks at this time in life, and to become more exploratory and curious, risky behavior can lead to problems for some youth – including serious injuries and growing dependence on self-destructive activities and substances, like drugs and alcohol. 

The ABCD study will be an unprecedented, scientific, “deep dive” into this period of development. ABCD will allow us to link the ongoing biological and functional development of the brains of our young volunteers to their strengthening cognitive, academic, social, and emotional functions. The study will also identify the roles of many of the factors that have an impact—for better or for worse—on the development of these functions. These include genetic, medical, and educational factors, but also the activities and experiences adolescents have, and the environments they grow up in, and their family, social, and cultural lives. 

There are many reasons why it’s important to begin this study now, but I’d like to highlight three of them that I think were particularly compelling.

First, several maturing technologies have made it possible to collect large-scale, highly informative datasets—unobtrusively—in observational studies like this with developing youth, and these include powerful brain imaging methods that allow us to measure many important characteristics of the biology and function of the brain in a short imaging session that is acceptable to children, and even fun at times; and other important technologies include new game-like methods for measuring children’s behavior, wearable devices for gathering activity and physiological data in real-time, and methods for assessing genetic variation precisely from a bit of saliva.

A second important reason is the maturing scientific workforce, and that is partly growth of expertise in the use of these research technologies, but also the formation of teams of behavioral, biomedical, and data science experts who have experience working together on multisite studies with high-dimensional data.

And finally, it is very clear that many rapid changes in our culture leave us with critical questions about their effects on the developing brain, particularly of adolescents. And these include trends like intensifying use of wireless and mobile devices and other screens in all aspects of our lives; increasingly competitive sporting activity that may in some cases place children at increased risk of injury; and of course we all know that there are widespread changes throughout our country in policies and practices regarding drugs, particularly marijuana—and many new forms and varieties of cannabis, nicotine products, and synthetic drugs with unknown effects on the developing brain and on the learning that young people need to do. So, these are a few of the most important reasons to embark upon this project now. 

We hope to learn more about the normal limits for individual developmental trajectories of brain development in youth. We also hope to learn about factors that have an impact (either by increasing resilience or increasing risk) on individual trajectories of brain, cognitive, and emotional development, and academic progress. We hope to learn about the relative roles of genetic versus environmental factors on development, as well as more about the interactions between these (for example, by analysis of data from 800 twin pairs).

We hope to learn about the effects of health, physical activity, sleep, as well as sports and other injuries on brain development and other outcomes. We hope to learn more about factors that influence the onset and progression of mental disorders and substance use disorders. And, specifically, how exposure to various levels and patterns of alcohol, nicotine, cannabis, caffeine, and other substances affect developmental outcomes and how other factors modify these effects.

This information is important—actually, critical—for more effectively preventing, mitigating, and treating behavioral disorders, by allowing us to target the truly causal factors and personalize these approaches in a way that reflects growing knowledge that risk and resilience will take different forms in different individuals.