Brain Imaging Unearths Neurobiological Roots of Resilience
CEN functional connectivity may contribute to the neurobiology of resilience.
Posted Nov 29, 2018
A new state-of-the-art brain imaging study from Northwestern University offers fresh clues about the neurobiology of resilience and helps to explain why some of us are better able to cope with significant stressors.
The brain networks involved with making someone more or less resilient has puzzled neuroscientists. So in pioneering research, Northwestern University psychologist Gregory E. Miller and his team set out to unearth the neurobiological roots of resilience using functional magnetic resonance (fMRI) brain imaging and asking the questions: Why is being exposed to neighborhood violence much more detrimental to the overall well-being of some young people than others? What brain networks are involved in how we respond to major life stressors?
Countless studies have identified a correlation between living in a high-crime neighborhood with an uptick in poor health marked by metabolic syndrome, asthma, and sleep loss. However, even children growing up in the same home can have very different psychophysiological responses to stress. Some kids are so-called “dandelion” children, who show incredible resilience even in the harshest conditions; whereas others are more like “orchid” children, who are more vulnerable to harsh environments.
For this study, the Northwestern researchers recruited 218 eighth-grade students from different neighborhoods around Chicago. Each neighborhood was scored based on violent crime and murder rates. Study participants were each given a cardiometabolic assessment that includes testing for insulin resistance, obesity, and overall metabolic syndrome. Then, participants had an fMRI neuroimaging scan to quantify the brain's functional connectivity.
Although students living in violent neighborhoods tend to have poorer metabolic health, those who lived in high-crime neighborhoods and maintained healthy biomarkers for stress also displayed higher connectivity within the brain's frontoparietal central executive network (CEN).
According to the researchers, the CEN is a brain hub that facilitates how we interpret threatening events, exercise self-control, and suppress unwanted emotional imagery. Based on these findings, it appears that resting-state connectivity within the central executive network may be an adaptive moderator that boosts resilience on a neurobiological level.
As the authors explain, “Across six distinct outcomes, a higher neighborhood murder rate was associated with greater cardiometabolic risk, but this relationship was apparent only among youth who displayed lower CEN resting-state connectivity. By contrast, there was little evidence of moderation by the anterior salience and default mode networks. These findings advance basic and applied knowledge about adaptation by highlighting intrinsic CEN connectivity as a potential neurobiological contributor to resilience.”
The researchers are quick to point out that this study has some limitations, such as its observational design. These findings are correlative and do not imply a causal link. Therefore, the authors strongly encourage a much larger longitudinal and multi-wave study to establish causality between CEN functional connectivity, neighborhood violence, cardiometabolic health, and the neurobiology of resilience.
That said, the researchers are hopeful that sometime in the near future these findings could lead to "network training" programs designed to enhance the functional connectivity of the brain's CEN network. Miller and colleagues speculate that these types of interventions have the potential to enhance "self-control, threat reappraisal, and thought suppression" in ways that could make at-risk teenagers more resilient.
Gregory E. Miller, Edith Chen, Casey C. Armstrong, Ann L. Carroll, Sekine Ozturk, Kelsey J. Rydland, Gene H. Brody, Todd B. Parrish, and Robin Nusslock. "Functional Connectivity in Central Executive Network Protects Youth Against Cardiometabolic Risks Linked with Neighborhood Violence." Proceedings of the National Academy of Sciences (First published online ahead of print: November 5, 2018) DOI: 10.1073/pnas.1810067115