FIU researchers assessed brain scans of nearly 12,000 9- to 11-year-olds searching for clues that could predict antisocial behavior, violence and aggression later in adolescence. After analyzing reward behavior in children, they found that not all conduct problems look the same at the neural level.
Of the nearly 12,000 scans, 995 had disruptive behavior disorders of which 198 also had high-levels of callous unemotional (CU) traits including a lack of empathy, reduced sensitivity to others’ emotions and a lack of guilt around breaking rules.
For this study, Samuel Hawes, research assistant professor in the Department of Psychology and faculty member at FIU’s Center for Children and Families, was specifically looking at the scans of children with CU traits and how they responded to rewards.
“We wanted to see what happens in the brain when these children anticipate and receive a reward in hopes that we could identify neural risk markers that can be used to inform personalized intervention and treatment efforts,” said Hawes. “There’s a long history in behavioral research suggesting that youth with severe behavioral problems have increased reward drive and continue to engage in reward-driven behaviors even when faced with serious punishment and other severe consequences, but previous fMRI results in this area are mixed.”
The study, published in the American Journal of Psychiatry, found that relative to typically developing youth, those with behavioral disorders, including those with CU traits, had decreased activity in the brain’s reward network while awaiting their prize but increased brain activity once they obtained it.
“Anticipation and receipt of a reward are associated with different aspects of reward-related decision-making,” Hawes says. “We were interested in looking at how brain activity in youth with behavior problems differed from that of typically developing youth.”
While lying in an MRI machine, participants were shown one of three colored shapes — a pink circle, yellow square, or blue triangle — signaling that they might win or lose money. After a brief delay, they then saw a target, again one of the colored shapes. To win money or avoid losing it, they had to respond by pressing a button within a certain timeframe.
“At the beginning of each trial, the participant sees how much money they could win. Once the target is presented and they press the button, there’s a moment when they anticipate that they’re going to be told they’ve won,” said Rebecca Waller , assistant professor at the University of Pennsylvania and co-author of the study. “Then they get feedback on the screen saying, ‘You’ve won $5’ or ‘You’ve won nothing’ or ‘You’ve lost.’ That’s the moment of receipt, so there’s separation in time between the feeling that they’re going to win and when they’re told they’ve actually won.”
Hawes says associations between environmental cues and rewards represent a key aspect of learning.
“Insight into how this process unfolds is essential, not only for understanding healthy development versus challenges to normal socialization and development, but also for shaping behaviors in more positive ways,” Hawes said.
In a prior study, Hawes and Waller measured gray matter volume in the brain using this same data. They found that compared to typically developing children, those with disruptive behavior disorders had less gray matter in the amygdala and hippocampus, areas associated with processing emotion and forming memories. Published in Biological Psychiatry: Cognitive Neuroscience and Neuroimaging, results suggests that early behavior problems do show up in the brain, often regardless of the presence or absence of CU traits.
Data for both studies came from the National Institutes of Health’s Adolescent Brain Cognitive Development (ABCD) Study, the largest long-term study of brain development and child health ever conducted in the United States. Launched in 2015, ABCD researchers are following nearly 12,000 9- to 11-year-olds for a decade, to understand how environmental, social, genetic and other biological factors affect brain and cognitive development.
The ABCD site at FIU, which is one of 21 sites nationwide, is led by Raul Gonzalez, professor of psychology, psychiatry and immunology, and a faculty member at FIU’s Center for Children and Families. Together with co-principal investigator Angela Laird, he leads the 14-member research team from FIU’s College of Arts, Sciences & Education and Robert Stempel College of Public Health & Social Work.