The effect of stress on reward-related activity in adolescents


September 13, 2017 - 1:00pm
Northwest Building, Room 243
About the Speaker
Sarah Hope Lincoln
Speaker Title: 
Post-doctoral Fellow
Speaker Affiliation: 

Adolescence is a period characterized by heightened reward sensitivity, increased stress exposure, and high rates of mental disorders. Both aberrant reward processing and stress have been implicated in a wide range of mental disorders including major depressive disorder, post-traumatic stress disorder, substance use disorders, and schizophrenia. Animal and human studies show that stress is associated with a blunted behavioral and neural response to rewards. At the same time, these methods fail to capture the degree of change in reward processing from pre- to post-stress conditions. This study tested whether acute social stress negatively impacted reward-related neural functioning in healthy adolescents. Forty adolescents (75% female) aged 12-14 years (M = 13.20, SD = 0.72) participants completed a monetary reward task (Carlson et al., 2011) under no-stress and stress conditions. We hypothesized that following an acute stressor, adolescents would exhibit: (a) reduced activation in the dorsal and ventral striatum following reward and (b) increased activation in the dorsal anterior cingulate cortex and the insula in response to loss. Participants also completed 3-month follow-up assessments probing psychiatric symptoms and stress, and we hypothesized that reduced activity in striatal regions following reward and increased activity in the dACC and insula in response to loss would predict depressive symptoms, anhedonia, and stress severity. Three principles findings emerged. First, relative to the no-stress condition, the stress condition elicited blunted neural response to reward in the right and left putamen and the right caudate. Second, changes in activation following stress within the left putamen predicted symptoms of perceived stress at the 3-month follow-up assessment. Finally, changes in activation following stress within the left and right insula predicted symptoms of perceived stress and anhedonia at the 3-month follow-up. In line with a diathesis-stress model, these findings indicate that the interaction between premorbid reward dysfunction and stress exposure may increase the risk for stress-related disorders in adolescence.