Neural response to rewards moderates the within-person association between daily positive events and positive affect during a period of stress exposure.

Stress and neural responses to reward can interact to predict psychopathology, but the mechanisms of this interaction are unclear. One possibility is that the strength of neural responses to reward can affect the ability to maintain positive affect during stress. In this study, 105 participants completed a monetary reward task to elicit the reward positivity (RewP), an event-related potential sensitive to rewards. Subsequently, during a stressful period, participants reported on their affect nine times a day and on daily positive and negative events for 10 days. Even during heightened stress, experiencing more positive events was associated with increased positive affect. The RewP significantly moderated this association: Individuals with a larger RewP reported greater increases in positive affect when they experienced more positive events, relative to individuals with a smaller RewP. A blunted RewP might contribute to stress susceptibility by affecting how much individuals engage in positive emotion regulation during stress.

Risk factors for the intergenerational transmission of depression in women and girls: Understanding neural correlates of major depressive disorder and the role of early-onset maternal depression.

Deficits in neural reward processing have been implicated in the etiology of depression and have been observed in high-risk individuals. However, depression is a heterogeneous disorder, and not all depressed individuals exhibit blunted neural reward response, suggesting the need to examine more specific depression phenotypes. Early-onset depression, a well-defined phenotype, has been associated with greater intergenerational transmission of depression and appears more closely linked to neural reward processing deficits. The present study examined whether a maternal history of early-onset depression was associated with neural reward response among mothers and their daughters. Mothers with and without a history of depression, as well as their biological, adolescent daughters (N = 109 dyads), completed a monetary reward guessing task while electroencephalogram was collected. Analyses focused on the Reward Positivity (RewP), an event-related potential following reward receipt. Adjusting for current depressive symptoms, maternal early-onset depression was associated with a blunted RewP in the mothers and a numerically smaller RewP in their never-depressed, adolescent daughters. Maternal adult-onset depression was not statistically associated with a blunted RewP in mothers or daughters. Thus, a blunted RewP appears to be a trait-like vulnerability marker for depression that emerges before depression onset and relates to more specific depression phenotypes (e.g., early-onset depression). These findings have implications for early identification of individuals at risk of depression and for developing more targeted interventions.

Maternal symptoms of depression and anxiety during the postpartum period moderate infants' neural response to emotional faces of their mother and of female strangers.

Affective exchanges between mothers and infants are key to the intergenerational transmission of depression and anxiety, possibly via adaptations in neural systems that support infants' attention to facial affect. The current study examined associations between postnatal maternal symptoms of depression, panic and social anxiety, maternal parenting behaviours, and infants' neural responses to emotional facial expressions portrayed by their mother and by female strangers. The Negative Central (Nc), an event-related potential component that indexes attention to salient stimuli and is sensitive to emotional expression, was recorded from 30 infants. Maternal sensitivity, intrusiveness, and warmth, as well as infant's positive engagement with their mothers, were coded from unstructured interactions. Mothers reporting higher levels of postnatal depression symptoms were rated by coders as less sensitive and warm, and their infants exhibited decreased positive engagement with the mothers. In contrast, postnatal maternal symptoms of panic and social anxiety were not significantly associated with experimenter-rated parenting behaviours. Additionally, infants of mothers reporting greater postnatal depression symptoms showed a smaller Nc to their own mother's facial expressions, whereas infants of mothers endorsing greater postnatal symptoms of panic demonstrated a larger Nc to fearful facial expressions posed by both their mother and female strangers. Together, these results suggest that maternal symptoms of depression and anxiety during the postpartum period have distinct effects on infants' neural responses to parent and stranger displays of emotion.

Cognitive effort exertion enhances electrophysiological responses to rewarding outcomes.

Recent work has highlighted neural mechanisms underlying cognitive effort-related discounting of anticipated rewards. However, findings on whether effort exertion alters the subjective value of obtained rewards are inconsistent. Here, we provide a more nuanced account of how cognitive effort affects subsequent reward processing in a novel task designed to assess effort-induced modulations of the Reward Positivity, an event-related potential indexing reward-related neural activity. We found that neural responses to both gains and losses were significantly elevated in trials requiring more versus less cognitive effort. Moreover, time-frequency analysis revealed that these effects were mirrored in gain-related delta, but not in loss-related theta band activity, suggesting that people ascribed more value to high-effort outcomes. In addition, we also explored whether individual differences in behavioral effort discounting rates and reward sensitivity in the absence of effort may affect the relationship between effort exertion and subsequent reward processing. Together, our findings provide evidence that cognitive effort exertion can increase the subjective value of subsequent outcomes and that this effect may primarily rely on modulations of delta band activity.