Substance Use Begins to Take Spotlight in Major Brain Development Study

The young people who comprise the cohort for the nation's largest study ever of brain development and child health have reached the 12-to-14 age range, meaning that substance use will occupy a central place in the study's next phase.

In an interview with Addiction Professional, the director of the Adolescent Brain Cognitive Development (ABCD) Project at the National Institute on Drug Abuse (NIDA) explains that this research will allow the scientific community to better understand the interrelationship between substance use and brain development. A long-term study with the capacity to look at the same individuals before and after they use substances will offer insights that cannot be generated with studies that compare substance users with non-users, says Gayathri J. Dowling, PhD.

Given recent findings from national substance use prevalence research, leaders of ABCD will have particular interest in vaping trends (for both nicotine and other substances) and their impact, Dowling says.

ABCD was launched in 2015 and is following nearly 12,000 children starting at ages 9 and 10. The investigators working at the 21 study sites across the country have recently renewed their participation in a study that intends to track young people for 10 years. Dowling explains that other researchers not directly involved with ABCD can access the study data via the National Institute of Mental Health (NIMH) Data Archive.

“We want the data to be used,” Dowling says. “People with other interests in adolescent development can mine the data and publish on it.”

She adds by way of example, “We can ask some very general questions on things like the effect of young people's screen time, but we don't have the bandwidth to go very deep on those questions. Others could drill down on this, and this could spur on more in-depth investigations.”

Why age 9 and 10?

Dowling explains that the research team would be eager to start a long-term brain development study with newborns, and says there are efforts to launch a study that would examine the trajectory from birth to age 10. Starting a study at ages 9 and 10 carries value for understanding substance use because researchers can explore the period just before some members of the cohort are likely to begin experimenting with substances, she says.

By contrast, some mental health-related factors were observable in the earliest stage of the study. There already have been two published papers on suicidal ideation, with the research showing a significant association with high family conflict and low parental supervision, Dowling says. “This does exist very early” in a small percentage of very young children, she says.

ABCD in general will help researchers and practitioners understand whether there is one trajectory of brain development in young people or multiple trajectories. Dowling says NIDA Director Nora Volkow would like to see something akin to height and weight growth charts introduced for the brain, serving as a tool to generate action if a young person appears to be falling behind norms in developmental progress.

The ABCD project is examining all of the variables believed to influence brain development, from behavioral health issues to youth activities to sleep. One goal involves achieving a better understanding of the factors that contribute to young people's initiation to substance use and progression in some cases from use to a disorder.

Carrying on in crisis

ABCD, which is mainly funded out of the general appropriations to the participating National Institutes of Health (NIH) institutes, has received additional funding for asking specific questions of families about how the coronavirus crisis is affecting them. Dowling says it is critical to capture this information given the major impact that “such a life-changing moment” is having on children and families.

With ABCD study sites not currently in operation because of the public health emergency, neuroimaging has had to be put on hold, but neurocognitive testing and other assessments continue to take place virtually. For a longitudinal analysis such as ABCD, taking a complete hiatus at a critical time and thus missing out on an important period for data collection is simply not an option.