Poster #13 - Adaptive Calibration of Mexican-Origin Adolescents’ Brain-Autonomic Coupling by Prior Threat Exposure

• In Event: 2-163 - Poster Session 08
  In Poster Session: PS 08 Section - Biological Processes: Neuroscience and Genetics

Integrative Statement

Past exposure to threat increases the risk for internalizing problems in adolescents. However, individual adaptations in the coordination of components of the stress response system to threat may differentiate adolescents who do and do not develop significant problems. This study investigated the role of medial prefrontal cortex (mPFC) regulation of autonomic nervous system (ANS) activity in calibrating adolescents’ emotional and physiological reactivity, leading to risk for or resilience to internalizing problems as a function of past threat exposure. 179 Mexican-origin adolescents (88 female) reported on neighborhood and school crime, peer victimization, and discrimination when they were 10, 12, 14, and 16 years old. At age 17, to quantify mPFC regulation of ANS activity during emotion processing, participants underwent a functional neuroimaging scan during which they viewed and rated pictures of emotional faces while measures of respiratory sinus arrhythmia (RSA) and skin conductance responses (SCRs) were collected simultaneously. Post scan, adolescents reported on their symptoms of internalizing problems. RSA across the faces task was found to be inversely related to activity in a 50 voxel cluster located in the ventral medial frontal gyrus (i.e. vmPFC; Center of Mass = 1, 51, -14). The number of SCRs across the faces task were found to be inversely related to activity in a 95 voxel cluster in the dorsal medial frontal gyrus (i.e. dmPFC; Center of Mass = -4, 49, 38). In order to investigate whether brain-ANS coupling mediates the link between threat and internalizing problems, regression coefficients were extracted from the vmPFC and dmPFC. Multilevel structural equation modelling in MPlus (Muthén & Muthén, 2017) was then used to identify the random slope of the within-person relations (a) between mean-centered activity in vmPFC and RSA (S1) and (b) between mean-centered activity in dmPFC and the number of SCRs (S2; Figure 1A). These random slopes were then used as between-subject variables in a structural equation model (Figure 1B). Greater exposure to threats earlier in adolescence was associated with more internalizing problems at age 17. Threat exposure was also associated with stronger negative coupling between the vmPFC and RSA. Stronger negative vmPFC-RSA coupling was associated with fewer internalizing problems (Figure 2). Our findings suggest that exposure to threats in the peer and neighborhood context puts Mexican-origin adolescents at risk for increased internalizing problems. However, in adolescence, the nervous system may adapt to threat exposure through stronger negative coupling of the vmPFC with the PNS, which is associated with decreased internalizing problems. These results indicate that neurophysiological adaptation to threat exposure through prefrontal cortex inhibition of physiological activity during emotion processing may contribute to risk for and resilience to internalizing problems. As these mechanisms are better understood, prefrontal regulation of PNS activity may prove to be a high leverage target for interventions to improve resiliency among adolescents in high threat environments. At a broader level, these findings supports the idea that adolescence is a developmental period in which neurophysiological functioning is still being calibrated by experience, making it a period not only of risk, but also of opportunity.

Authors

• David Gerrick Weissman, Harvard University
  Presenting Author

• Amanda Guyer, University of California, Davis
  Non-Presenting Author

• Richard W. Robins, University of California, Davis
  Non-Presenting Author

• Paul Hastings, University of California, Davis
  Non-Presenting Author