Poster #25 - Blunted striatal reward prediction error signals in adolescent depression

• In Event: 3-053 - Poster Session 10
  In Poster Session: PS 10 Section - Cognitive Processes

Integrative Statement

Depression is a devastating mental health disorder that often emerges in adolescence. Despite its prevalence during this critical developmental period, little is known about the neural mechanisms that underlie depressive symptoms in adolescence, nor the extent to which they mirror the pathophysiology of adult depression. One such patho-mechanism is altered striatal signaling during reinforcement learning. Prior studies in adults have found that depressed patients reliably exhibit blunted BOLD signal in response to positive prediction errors. Neural processing of reward has been widely studied both developmentally and in various patient populations, however the findings have been inconsistent at the intersection of adolescence and depression (Dahl & Forbes, 2012). In this study, we examined the neural mechanisms underlying reward processing in a sample of adolescents (Mean Age = 15.79, 72% female) with major depressive disorder (n=18) and healthy controls without psychological diagnoses (n=21). Using fMRI during a probabilistic reinforcement learning task (Pessiglione, et al., 2006), we found that adolescents with depression were less likely to select the optimal (i.e. most rewarding) option and showed less ventral striatal activation to positive prediction errors relative to controls. This effect was strongest during trials in which a positive prediction error signaled avoiding a potential loss (Small Volume Corrected – Left NAcc pFWE-corr=0.005; Right NAcc pFWE-corr=0.020). All analyses controlled for age. To the best of our knowledge, these data are the first demonstration that depressed adolescents exhibit attenuated striatal reward prediction error signaling during reinforcement learning.

Authors

• Brittany A DeVries, Emory University
  Presenting Author

• Allison M LoPilato, Emory University
  Non-Presenting Author

• Jessica A Cooper, Emory University
  Non-Presenting Author

• Ellen M Andrews, Emory University
  Non-Presenting Author

• W. Edward Craighead, Emory University
  Non-Presenting Author

• Michael T Treadway, Emory University
  Non-Presenting Author