Electrocortical measures of win and loss processing are associated with mesocorticolimbic functional connectivity: A combined ERP and rs-fMRI study

Depth recordings of the mouse homologue of the Reward Positivity

We recently advanced a rodent homologue for the reward-specific, event-related potential component observed in humans known as the Reward Positivity. We sought to determine the cortical source of this signal in mice to further test the nature of this homology. While similar reward-related cortical signals have been identified in rats, these recordings were all performed in cingulate gyrus. Given the value-dependent nature of this event, we hypothesized that more ventral prelimbic and infralimbic areas also contribute important variance to this signal. Depth probes assessed local field activity in 29 mice (15 males) while they completed multiple sessions of a probabilistic reinforcement learning task. Using a priori regions of interest, we demonstrated that the depth of recording in the cortical midline significantly correlated with the size of reward-evoked delta band spectral activity as well as the single trial correlation between delta power and reward prediction error. These findings provide important verification of the validity of this translational biomarker of reward responsiveness, learning, and valuation.

Neural reward responsiveness and daily positive affect functioning in adolescent girls

Deficits in reward processing have been implicated in the development of many forms of psychopathology, especially major depressive disorder (MDD). One facet of reward processing, known as reward responsivity, has been associated with the development and maintenance of depression across development. The reward positivity (RewP) is an event-related potential derived from electroencephalogram (EEG), which is thought to reflect reward responsivity. An attenuated RewP has been observed in both currently depressed individuals and youth at risk for depression, suggesting it may represent a biomarker of depression. Despite this, little is known about how the RewP translates to behavior and affect in the real world. In the current study, we examined how the RewP relates to real world emotional functioning, measured using ecological momentary assessment (EMA). Thirty-eight female adolescents (ages 11-16, Mage = 13.9 years) participated in the study; approximately half of the sample were considered high risk due to maternal lifetime history of MDD. Adolescents completed a monetary reward task while EEG was recorded, followed by a 10-day period of EMA assessing daily affect and emotion regulation strategy use following positive events. Results revealed that the RewP was positively associated with subjective reports of positive, but not negative, daily affect. Results also revealed that the RewP was positively associated with focusing on positive feelings following a positive event (e.g., savoring). Findings from this preliminary study highlight how neural responses to reward in the lab relate to daily life emotional functioning, supporting the RewP as an ecologically valid marker of positive affect functioning among youth.