Give me feedback. Outcome phases of punishment and reward processes during a Monetary Incentive Delay task (MID).

Introduction: Brain processes in reward consummation and punishment are linked to the subjective feeling of (dis-)satisfaction. An appropriate emotional reaction to external feedback is an important evolutionary function and is often impaired in psychopathology. One’s reaction towards rewarding feedback can be dependent on the entity: directly receiving reward versus avoidance of loss. To date, most studies did not differentiate between the entity of the reward/punishment: it is unclear if positive and negative reward and punishment outcomes share the same neural correlates. Methods: Sixty healthy subjects (age = 16-25 yrs, M/F = 14/46) underwent an fMRI scan with the monetary incentive delay task. Image pre-processing and statistical analyses were done in SPM8. Results: There was a significant main effect of feedback value in bilateral caudate nucleus, frontopolar prefrontal cortex, and right insula (pcorr < 0.01). Post hoc T-test showed higher activation to reward outcome in caudate bilaterally, left dorsal anterior cingulate cortex (ACC) and frontopolar prefrontal cortex activity (pcorr < 0.01); the insula bilaterally was significantly more activated during punishment (pcorr < 0.01). There was no interaction effect between feedback and entity. Conclusions: insula’s role in negative feeling perception is extended to the punishment outcome. The caudate, dorsal ACC, and prefrontal cortex seem to be designed for coding and response to positive feedback. Since, the caudate nucleus seems involved in the consummatory phase of reward in relation to anhedonia, in future analyses we will assess the stability of the interaction between feedback and entity taking into account the effect of anhedonia.