The Role of Social Reward and Corticostriatal Connectivity in Substance Use

Abstract

This report describes an ongoing R03 grant that explores the links between trait reward sensitivity, substance use, and neural responses to social and nonsocial reward. Although previous research has shown that trait reward sensitivity and neural responses to reward are linked to substance use, whether this relationship is impacted by how people process social stimuli remains unclear. We are investigating these questions via a neuroimaging study with college-aged participants, using individual difference measures that examine the relation between substance use, social context, and trait reward sensitivity with tasks that measure reward anticipation, strategic behavior, social reward consumption, and the influence of social context on reward processing. We predict that substance use will be tied to distinct patterns of striatal dysfunction. Specifically, reward hyposensitive individuals will exhibit blunted striatal responses to social and non-social reward and enhanced connectivity with the orbitofrontal cortex; in contrast, reward hypersensitive individuals will exhibit enhanced striatal responses to social and non-social reward and blunted connectivity with the orbitofrontal cortex. We also will examine the relation between self-reported reward sensitivity, substance use, and striatal responses to social reward and social context. We predict that individuals reporting the highest levels of substance use will show exaggerated striatal responses to social reward and social context, independent of self-reported reward sensitivity. Examining corticostriatal responses to reward processing will help characterize the relation between reward sensitivity, social context and substance use while providing a foundation for understanding risk factors and isolating neurocognitive mechanisms that may be targeted to increase the efficacy of interventions.

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

“…Although we originally planned to study Machiavellianism, due to an error in data collection, this survey was not completed by our participants. Next, whereas substance use analyses were not mentioned in the pre-registration, we intended to complete them in accordance with the broader aims and hypotheses of the grant, which are also described in the grant report (Sazhin et al, 2020). Third, we used the (Clithero & Rangel, 2014) (-2, 28, -18) meta-analysis vmPFC coordinates for our mask rather than the mask specified in the pre-registration (Delgado et al, 2016) for greater spatial specificity in our analyses.…”

“…Reward sensitivity has been studied as a clinical measure (Alloy et al, 2016; Carver & White, 1994; Nusslock & Alloy, 2017), revealing that people who are hyper and hyposensitive to rewards are at risk for substance use and bipolar or depressive disorders (Bart et al, 2021). However, little is known about how corticostriatal connectivity is modulated by reward sensitivity (Sazhin et al, 2020). For instance, people who are more sensitive to rewards may overvalue their initial endowment in UG and DG contexts and may be loath to share it with a stranger.…”

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

“…A rich body of literature has demonstrated evidence of corticostriatal response during reward-related tasks (J. P. Bhanji & Delgado, 2014; Dobryakova & Smith, 2022; Knutson et al, 2000; O’Doherty et al, 2017; Sazhin et al, 2020), noting links between the areas described as the “social brain” and the striatum when introducing social context (Fareri et al, 2022; Fareri & Delgado, 2014; Kwon et al, 2022; Lockwood et al, 2020). Likewise, trait reward sensitivity has been noted as a significant factor in neural reward response (Chat et al, 2022).…”

“…A key metric in understanding individual variation in the neural reward response is trait reward sensitivity, or the degree to which rewarding stimuli motivate approach behavior (Carver & White, 1994; Haber & Knutson, 2010; Kim et al, 2015; Nusslock et al, 2007). However, the relationship between reward sensitivity and social context in influencing the function of neural reward circuitry remains severely understudied (Sazhin et al, 2020). Aberrant approach motivation is linked to dysfunctional reward processing (Chat et al, 2022), mood disorders, and increased vulnerability to addiction and substance use (Nusslock & Alloy, 2017; Volkow et al, 2010), which are in turn linked to altered striatal connectivity (Kober et al, 2010).…”

Meta-Analysis Reveals That Explore-Exploit Decisions are Dissociable by Activation in the Dorsal Lateral Prefrontal Cortex, Anterior Insula, and the Anterior Cingulate Cortex

“…People with greater alcohol use tend to avoid uncertainty (L. S. Morris et al 2016) and explore less. Brain responses may be modulated by substance use and mediated by social context (Sazhin et al 2020). Sharing rewards with friends decreased connectivity between VS and dorsomedial prefrontal cortex (Wyngaarden et al 2023), suggesting that social contexts are an important feature of understanding substance use decisions.…”