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Fareri, D.

Publications and source records attributed to Fareri, D..

5 recordsLinked to original sources

Social Context and Reward Sensitivity Enhance Corticostriatal Function during Experiences of Shared Rewards

Although prior research has demonstrated enhanced striatal response when sharing rewards with close social connections, less is known about how individual differences affect ventral striatal (VS) activation and connectivity when experiencing rewards within social contexts. Given that self-reported reward sensitivity and level of substance use have been associated with differences in VS activation, we set out to investigate whether these factors would be independently associated with enhancements to neural reward responses within social contexts. In this pre-registered study, participants (N=45) underwent fMRI while playing a card guessing game in which correct or incorrect guesses resulted in monetary gains and losses that were shared evenly with either a close friend, stranger (confederate), or non-human partner. Consistent with our prior work, we found increased VS activation when sharing rewards with a socially close peer as opposed to an out-of-network stranger. As self-reported reward sensitivity increased, the difference in VS response to rewards shared with friends and strangers decreased. We also found enhanced connectivity between the VS and temporoparietal junction when sharing rewards with close friends as opposed to strangers. Finally, exploratory analyses revealed that as reward sensitivity and sub-clinical substance use increase, the difference in VS connectivity with the right fusiform face area increases as a function of social context. These findings demonstrate that responsivity to the context of close friends may be tied to individual reward sensitivity or sub-clinical substance use habits; together these factors may inform predictions of risk for future mental health disorders.

neuroscience↗

Trait Reward Sensitivity Modulates Connectivity with the Temporoparietal Junction and Anterior Insula during Strategic Decision Making

Many decisions happen in social contexts such as negotiations, yet little is understood about how people balance fairness versus selfishness. Past investigations found that activation in brain areas involved in executive function and reward processing was associated with people offering less with no threat of rejection from their partner, compared to offering more when there was a threat of rejection. However, it remains unclear how trait reward sensitivity may modulate activation and connectivity patterns in these situations. To address this gap, we used task-based fMRI to examine the relation between reward sensitivity and the neural correlates of bargaining choices. Participants (N = 54) completed the Sensitivity to Punishment (SP)/Sensitivity to Reward (SR) Questionnaire and the Behavioral Inhibition System/Behavioral Activation System scales. Participants performed the Ultimatum and Dictator Games as proposers and exhibited strategic decisions by being fair when there was a threat of rejection, but being selfish when there was not a threat of rejection. We found that strategic decisions evoked activation in the Inferior Frontal Gyrus (IFG) and the Anterior Insula (AI). Next, we found elevated IFG connectivity with the Temporoparietal junction (TPJ) during strategic decisions. Finally, we explored whether trait reward sensitivity modulated brain responses while making strategic decisions. We found that people who scored lower in reward sensitivity made less strategic choices when they exhibited higher AI-Angular Gyrus connectivity. Taken together, our results demonstrate how trait reward sensitivity modulates neural responses to strategic decisions, potentially underscoring the importance of this factor within social and decision neuroscience.

neuroscience↗

Substance use is related to differential activation and connectivity for social relative to monetary rewards

Aberrant levels of reward sensitivity have been linked to substance use disorder and are characterized by alterations in reward processing in the ventral striatum (VS). Less is known about how reward sensitivity and subclinical substance use relate to striatal function during social rewards (e.g., positive peer feedback). Testing this relation is critical for predicting risk for development of substance use disorder. In this pre-registered study, participants (N=44) underwent fMRI while completing well-matched tasks that assess neural response to reward in social and monetary domains. Contrary to our hypotheses, aberrant reward sensitivity blunted the relationship between substance use and striatal activation during receipt of rewards, regardless of domain. Moreover, exploratory whole-brain analyses showed unique relations between substance use and social rewards in temporoparietal junction. Psychophysiological interactions demonstrated that aberrant reward sensitivity is associated with increased connectivity between the VS and ventromedial prefrontal cortex during social rewards. Finally, we found that substance use was associated with decreased connectivity between the VS and dorsomedial prefrontal cortex for social rewards, independent of reward sensitivity. These findings demonstrate nuanced relations between reward sensitivity and substance use, even among those without substance use disorder, and suggest altered reward-related engagement of cortico-VS responses as potential predictors of developing disordered behavior.

neuroscience↗

A neural signature of reward

Using a neurometric approach, we identify and validate a neural signature of reward encoded in a distributed pattern of brain activity using data collected from 21 different studies (N = 2,691). Our model can discriminate between receiving rewards from punishments in completely independent data with 99% accuracy and includes weights located in regions containing a high density of D2/D3 receptors. The model exhibits strong generalizability across a range of tasks probing reward, and a high degree of specificity for reward compared to non-reward constructs. We demonstrate several applications of how this model can infer psychological states of positive affect in the absence of self report. The model is sensitive to changes in brain activity following causal manipulations of homeostatic states, can uncover individual preferences for loss-aversion, and can be used to identify positive affective experiences when watching a television show. Our results suggest that there is a shared neural signature of reward elicited across these different task contexts.

neuroscience↗

Towards a Neurometric-based Construct Validity of Trust

Trust is a nebulous construct central to successful cooperative exchanges and interpersonal relationships. In this study, we introduce a new approach to establishing construct validity of trust using "neurometrics". We develop a whole-brain multivariate pattern capable of classifying whether new participants will trust a relationship partner in the context of a cooperative interpersonal investment game (n=40) with 90% accuracy and find that it also generalizes to a variant of the same task collected in a different country with 82% accuracy (n=17). Moreover, we establish the convergent and discriminant validity by testing the pattern on thirteen separate datasets (n=1,427) and find that trust is reliably related to beliefs of safety, inversely related to negative affect, but unrelated to reward, cognitive control, social perception, theory of mind, and self-referential processing. Together these results provide support for the notion that the psychological experience of trust contains elements of beliefs of reciprocation and fear of betrayal aversion. Contrary to our predictions, we found no evidence that trust is related to anticipated reward. This work demonstrates how "neurometrics" can be used to characterize the psychological processes associated with brain-based multivariate representations.

neuroscience↗