Objective: Youths with disruptive behavior disorders (DBDs) and a history of trauma exposure often exhibit deficits in neural mechanisms related to reward anticipation and assessment. This preliminary investigation examines the potential of a serotonergic agent (fluoxetine) to modulate neural activity in reward-related pathways for this population. Methods: Three participant groups were: (i) youth with DBDs and trauma exposure who received fluoxetine treatment for 8 weeks (n = 12); (ii) a matched group of youth with DBDs and trauma exposure who received routine regular followup in an outpatient clinic (n = 9); and (iii) typically developing youth (n = 19). All participants completed a passive avoidance fMRI task twice, 8 weeks apart (pre-treatment and post treatment for youth with DBDs). Results: Youth with DBDs and trauma exposure who received fluoxetine treatment compared to the other two groups showed: (i) significant improvement in externalizing, oppositional defiant disorder, irritability, anxiety-depression, and trauma-related symptoms; (ii) significantly increased recruitment of regions implicated in reward expectation (e.g., ventral tegmental area, nucleus accumbens), monitoring prediction error (e.g., dorsolateral prefrontal cortex, posterior parietal cortex), and inhibitory control (e.g., anterior insula, pre-supplementary motor area, anterior prefrontal cortex. Conclusion We provide preliminary data suggesting that a serotonergic medication can correct reward processing and provide symptom improvement in youth with DBDs and a history of trauma exposure. Given the small sample size, more rigorous studies with larger sample size are needed to confirm these results. The findings of this study could aid future clinical research and treatment for this challenging population.

OBJECTIVE: In the current study we investigated neurodevelopmental changes in response to social and non-social reinforcement. METHODS: Fifty-three healthy participants including 16 early adolescents (age, 10–15 years), 16 late adolescents (age, 15–18 years), and 21 young adults (age, 21–25 years) completed a social/non-social reward learning task while undergoing functional magnetic resonance imaging. Participants responded to fractal image stimuli and received social or non-social reward/non-rewards according to their accuracy. ANOVAs were conducted on both the blood oxygen level dependent response data and the product of a context-dependent psychophysiological interaction (gPPI) analysis involving ventromedial prefrontal cortex (vmPFC) and bilateral insula cortices as seed regions. RESULTS: Early adolescents showed significantly increased activation in the amygdala and anterior insula cortex in response to non-social monetary rewards relative to both social reward/non-reward and monetary non-rewards compared to late adolescents and young adults. In addition, early adolescents showed significantly more positive connectivity between the vmPFC/bilateral insula cortices seeds and other regions implicated in reinforcement processing (the amygdala, posterior cingulate cortex, insula cortex, and lentiform nucleus) in response to non-reward and especially social non-reward, compared to late adolescents and young adults. CONCLUSION: It appears that early adolescence may be marked by: (i) a selective increase in responsiveness to non-social, relative to social, rewards; and (ii) enhanced, integrated functioning of reinforcement circuitry for non-reward, and in particular, with respect to posterior cingulate and insula cortices, for social non-reward.
Adolescent ; Amygdala ; Fractals ; Gyrus Cinguli ; Healthy Volunteers ; Humans ; Learning ; Magnetic Resonance Imaging* ; Oxygen ; Prefrontal Cortex ; Reinforcement, Social* ; Reward ; Young Adult