Yale was recently selected to be a part of a 10-year study focused on the brain growth and development of 10,000 adolescents across the country.

The Adolescent Brain Cognitive Development Study, or ABCD, is the largest long-term brain imaging and child development study to be done in the United States. Looking at factors including mental health, extracurriculars, alcohol and drug use, the study will assess how these affect brain development and behavior. Yale is one of 19 research locations across the country selected to conduct the study, with a research team led by psychology professor BJ Casey. The study will include qualitative meetings with the adolescents, biospecimen collection and biannual brain scans of the 10,000 children.

According to the study investigators, the ABCD study is the first of its kind in the U.S. and will offer a wealth of data for research purposes.

“I cannot emphasize enough how unprecedented ABCD is,” said Chandra Sripada, a co-investigator for the study at University of Michigan.

Terry Jernigan, co-director of the ABCD study and cognitive science professor at the University of San Diego, described this study as “a deep dive into the life of an adolescent.” It will start with children who are only 9 or 10 years old and will follow them through adolescence. Due to its size and scope, this data will give researchers the ability to track individual developmental trajectories, including brain, cognitive, emotional and academic, and the factors that influence them.

“This is a time in life when some of the first signs of very significant problems occur that may afflict people for quite a long time,” Jernigan said.

Researchers will track the onset and progression of mental disorders as well as experimentation with alcohol, tobacco and other drugs. Jernigan also plans to analyze the impact of changing state laws, especially with cannabis use, and the effects on usage among teens.

The researchers will examine the effects of physical activity, screen time and sport-related brain injuries. Starting before these children hit adolescence, this study will track brain development from start to finish through this “tumultuous time,” Jernigan added.

Casey believes that “this is a once in a lifetime study” in the United States. She hopes it will provide a wealth of knowledge about factors that impact the developing brain and the well-being and success of youth.

“The more information we can get about circumstances and development that [are] associated with positive outcomes, the more we can help provide those opportunities for as many youth in the United States as possible,” she said.

There will be phone call appointments every three to six months, yearly meetings and a brain scan every two years. With 10,000 kids for 10 years, this means there will be on the order of 50,000 brain scans.

Sripada has worked on studies where 30 brain scans is considered a large amount of data. Five hundred brain scans will give Sripada and other researchers an unprecedented amount of both cross-sectional and longitudinal data for analysis.

“This is a Manhattan Project for brain imaging,” Sripada said. “It’s a game changer.”

Researchers hope to include all subsets of the U.S. population, including all races and ethnicities, coverage of the whole socioeconomic strata and those in both urban and rural communities. To mirror the diversity statistics present in the U.S., researchers will recruit through schools picked by an epidemiological team, who will then send information packets to families. Once the first round of families commits to the study, researchers will contact another set of schools in order to target groups not adequately represented. The study will consist primarily of parent and self-reports.

“It’s amazing what kids will tell you if they’re confident you will keep this information confidential,” Jernigan said.

To verify this information, especially about drug and alcohol use, researchers plan to take biospecimen including urine, saliva and hair samples, which show environmental exposures to a high degree of accuracy. Researchers are also considering tracking social media accounts, but only with permission of the adolescents.

Once relationships are formed with researchers, children may reveal facts about themselves that could lead the researchers to feel concern for their safety.

“The safety of the child is always foremost in our minds, [and] by law, there are certain things that would force us to break confidentiality,” Jernigan said, but only if the researchers learn either of neglect of a child or elder, or feel the child has the intention to hurt themselves or another. “We have to gather this information to protect children in general,” Jernigan added, so intervention will only occur in extreme cases. Casey said these instances will help people learn how to connect individuals to the services that they need.

Along with the 10,000 adolescents from schools, researchers will also study 800 twin pairs. Gaya Dowling, the director of the ABCD study for the National Institutes of Health, hopes the information gathered from these twin pairs will help “disentangle the roles of genetics and environment.”

The study is funded by the NIH, which has so far committed $150 million but may end up spending as much as $300 million. They have committed to funding for the next 10 years.