Being the Gatekeeper: How Thinking about Sharing Affects Neural Encoding of Information

Information transmission in a society depends on individuals' intention to share or not. Yet, little is known about whether being the gatekeeper shapes the brain's processing of incoming information. Here, we examine how thinking about sharing affects neural encoding of information, and whether this effect is moderated by the person's real-life social network position. In an functional magnetic resonance imaging study, participants rated abstracts of news articles on how much they wanted to read for themselves (read) or-as information gatekeepers-to share with a specific other (narrowcast) or to post on their social media feed (broadcast). In all conditions, consistent spatial blood oxygen level-dependent patterns associated with news articles were observed across participants in brain regions involved in perceptual and language processing as well as higher-order processes. However, when thinking about sharing, encoding consistency decreased in higher-order processing areas (e.g., default mode network), suggesting that the gatekeeper role involves more individualized processing in the brain, that is, person- and context-specific. Moreover, participants whose social networks had high ego-betweenness centrality (i.e., more likely to be information gatekeeper in real life) showed more individualized encoding when thinking about broadcasting. This study reveals how gatekeeping shapes our brain's processing of incoming information.

Social networks and neural receptivity to persuasive health messages

OBJECTIVE

Health-related norms in social networks can influence whether people are open to health behavior change. Yet, little is known about how social networks relate to the ways individual brains respond to persuasive health messaging. The current study focuses on ventromedial prefrontal cortex (VMPFC) activity as an index of neural receptivity to health messages that may be related to behavior change. The study tested whether health-related norms and perceived physical activity levels within participants' social networks are associated with neural receptivity to health messages.

METHOD

Adults who initially reported under 200 minutes/week of physical activity (N = 146) rated the perceived physical activity levels of, and closeness to, each person in their core social network. VMPFC activity was monitored using fMRI while participants viewed persuasive health messages promoting physical activity. Longitudinal changes in sedentary behavior were objectively logged using wrist-worn accelerometers throughout a 2-week baseline and the month following the fMRI scan.

RESULTS

Higher levels of perceived physical activity in participants' social networks were associated with greater VMPFC activity during message exposure, which in turn were associated with greater decreases in sedentary minutes. By contrast, greater closeness to physically inactive social ties was associated with lower VMPFC activity.

CONCLUSIONS

Perceived norms in social networks relate to neural receptivity to health messaging. In particular, closeness to physically inactive ties is associated with lower neural receptivity to health messages encouraging physical activity, which may undermine the effectiveness of health messages. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Brain Activity Tracks Population Information Sharing by Capturing Consensus Judgments of Value

Information that is shared widely can profoundly shape society. Evidence from neuroimaging suggests that activity in the ventromedial prefrontal cortex (vmPFC), a core region of the brain's valuation system tracks with this sharing. However, the mechanisms linking vmPFC responses in individuals to population behavior are still unclear. We used a multilevel brain-as-predictor approach to address this gap, finding that individual differences in how closely vmPFC activity corresponded with population news article sharing related to how closely its activity tracked with social consensus about article value. Moreover, how closely vmPFC activity corresponded with population behavior was linked to daily life news experience: frequent news readers tended to show high vmPFC across all articles, whereas infrequent readers showed high vmPFC only to articles that were more broadly valued and heavily shared. Using functional connectivity analyses, we found that superior tracking of consensus value was related to decreased connectivity of vmPFC with a dorsolateral PFC region associated with controlled processing. Taken together, our results demonstrate variability in the brain's capacity to track crowd wisdom about information value, and suggest (lower levels of) stimulus experience and vmPFC-dlPFC connectivity as psychological and neural sources of this variability.

Neural processes during adolescent risky decision making are associated with conformity to peer influence

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Adolescents’ neural responses to risky decisions may modulate their conformity to different types of peer influence.

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Neural activity in the anterior cingulate cortex (ACC) predicted conformity to risky peers while driving.

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Connectivity between VS and risk processing regions (including insula and ACC) predicted safer driving under risky influence.

Adolescents demonstrate both heightened sensitivity to peer influence and increased risk-taking. The current study provides a novel test of how these two phenomena are related at behavioral and neural levels. Adolescent males (N = 83, 16–17 years) completed the Balloon Analogue Risk Task (BART) in an fMRI scanner. One week later, participants completed a driving task in which they drove alone and with a safety- or risk-promoting peer passenger. Results showed that neural responses during BART were associated with participants’ behavioral conformity to safe vs. risky peer influence while later driving. First, the extent that neural activation in the anterior cingulate cortex (ACC) scaled with decision stakes in BART was associated with conformity to risky peer influence. Additionally, stake-modulated functional connectivity between ventral striatum (VS) and risk processing regions (including ACC and insula) was associated with safer driving under risky peer influence (i.e. resistance to risky peer influence), suggesting that connectivity between VS and ACC as well as insula may serve a protective role under risky peer influence. Together, these results suggest that adolescents’ neural responses to risky decision making may modulate their behavioral conformity to different types of peer influence on risk taking.

Combining Crowd-Sourcing and Automated Content Methods to Improve Estimates of Overall Media Coverage: Theme Mentions in E-cigarette and Other Tobacco Coverage

Exposure to media content can shape public opinions about tobacco. Accurately describing content is a first step to showing such effects. Historically, content analyses have hand-coded tobacco-focused texts from a few media sources which ignored passing mention coverage and social media sources, and could not reliably capture over-time variation. By using a combination of crowd-sourced and automated coding, we labeled the population of all e-cigarette and other tobacco-related (including cigarettes, hookah, cigars, etc.) 'long-form texts' (focused and passing coverage, in mass media and website articles) and social media items (tweets and YouTube videos) collected May 2014-June 2017 for four tobacco control themes. Automated coding of theme coverage met thresholds for item-level precision and recall, event validation, and weekly-level reliability for most sources, except YouTube. Health, Policy, Addiction and Youth themes were frequent in e-cigarette long-form focused coverage (44%-68%), but not in long-form passing coverage (5%-22%). These themes were less frequent in other tobacco coverage (long-form focused (13-32%) and passing coverage (4-11%)). Themes were infrequent in both e-cigarette (1-3%) and other tobacco tweets (2-4%). Findings demonstrate that passing e-cigarette and other tobacco long-form coverage and social media sources paint different pictures of theme coverage than focused long-form coverage. Automated coding also allowed us to code the amount of data required to estimate reliable weekly theme coverage over three years. E-cigarette theme coverage showed much more week-to-week variation than did other tobacco coverage. Automated coding allows accurate descriptions of theme coverage in passing mentions, social media, and trends in weekly theme coverage.

Cognitive regulation of ventromedial prefrontal activity evokes lasting change in the perceived self-relevance of persuasive messaging

Persuasive messages can change people's thoughts, feelings, and actions, but these effects depend on how people think about and appraise the meaning of these messages. Drawing from research on the cognitive control of emotion, we used neuroimaging to investigate neural mechanisms underlying cognitive regulation of the affective and persuasive impact of advertisements communicating the risks of binge drinking, a significant public health problem. Using cognitive control to up-regulate (vs. down-regulate) responses to the ads increased: negative affect related to consequences of excessive drinking, perceived ad effectiveness, and ratings of ad self-relevance made after a one-hour delay. Neurally, these effects of cognitive control were mediated by goal-congruent modulation of ventromedial prefrontal cortex and distributed brain patterns associated with negative emotion and subjective valuation. These findings suggest that people can leverage cognitive control resources to deliberately shape responses to persuasive appeals, and identify mechanisms of emotional reactivity and integrative valuation that underlie this ability. Specifically, brain valuation pattern expression mediated the effect of cognitive goals on perceived message self-relevance, suggesting a role for the brain's valuation system in shaping responses to persuasive appeals in a manner that persists over time.

Neural Mechanisms of Emotion Regulation Moderate the Predictive Value of Affective and Value-Related Brain Responses to Persuasive Messages

Emotionally evocative messages can be an effective way to change behavior, but the neural pathways that translate messages into effects on individuals and populations are not fully understood. We used a human functional neuroimaging approach to ask how affect-, value-, and regulation-related brain systems interact to predict effects of graphic anti-smoking messages for individual smokers (both males and females) and within a population-level messaging campaign. Results indicated that increased activity in the amygdala, a region involved in affective reactivity, predicted both personal quit intentions and population-level information-seeking and this was mediated by activity in ventromedial prefrontal cortex (vmPFC), a region involved in computing an integrative value signal. Further, the predictive value of these regions was moderated by expression of a meta-analytically defined brain pattern indexing emotion regulation. That is, amygdala and vmPFC activity strongly tracked with population behavior only when participants showed low recruitment of this brain pattern, which consists of regions involved in goal-driven regulation of affective responses. Overall, these findings suggest that affective and value-related brain responses can predict the success of persuasive messages and that neural mechanisms of emotion regulation can shape these responses, moderating the extent to which they track with population-level message impact.SIGNIFICANCE STATEMENT People and organizations often appeal to our emotions to persuade us, but how these appeals engage the brain to drive behavior is not fully understood. We present an fMRI-based model that integrates affect-, control-, and value-related brain responses to predict the impact of graphic anti-smoking stimuli within a small group of smokers and a larger-scale public messaging campaign. This model indicated that amygdala activity predicted the impact of the anti-smoking messages, but that this relationship was mediated by ventromedial prefrontal cortex and moderated by expression of a distributed brain pattern associated with regulating emotion. These results suggest that neural mechanisms of emotion regulation can shape the extent to which affect and value-related brain responses track with population behavioral effects.

Adolescents' Neural Response to Tobacco Prevention Messages and Sharing Engagement

INTRODUCTION

Interpersonal communication can reinforce media effects on health behavior. Recent studies have shown that brain activity in the medial prefrontal cortex during message exposure can predict message-consistent behavior change. Key next steps include examining the relationship between neural responses to ads and measures of interpersonal message retransmission that can be collected at scale.

METHODS

Neuroimaging, self-report, and automated linguistic measures were utilized to investigate the relationships between neural responses to tobacco prevention messages, sharing engagement, and smoking-relevant belief changes. Thirty-seven adolescent nonsmokers viewed 12 ads from the U.S. Food and Drug Administration's "The Real Cost" campaign during a functional magnetic resonance imaging scan session (2015-2016). Data were analyzed between 2016 and 2017. The extent that participants talked in detail about the main message of the ads, or sharing engagement, was measured through transcripts of participants' subsequent verbal descriptions using automated linguistic coding. Beliefs about the consequences of smoking were measured before and after the main experiment using surveys.

RESULTS

Increased brain activation in self- and value-related subregions of the medial prefrontal cortex during message exposure was associated with subsequent sharing engagement when participants verbally talked about the ads. In addition, sharing engagement was significantly associated with changes in participants' beliefs about the social consequences of smoking.

CONCLUSIONS

Neural activity in self- and value-related subregions of the medial prefrontal cortex during exposure to "The Real Cost" campaign was associated with subsequent sharing engagement, which in turn was related to social belief change. These results provide new insights into the link between neurocognitive responses to ads, the content of interpersonal sharing, and downstream health-relevant outcomes.

SUPPLEMENT INFORMATION

This article is part of a supplement entitled Fifth Anniversary Retrospective of "The Real Cost," the Food and Drug Administration's Historic Youth Smoking Prevention Media Campaign, which is sponsored by the U.S. Food and Drug Administration.

Continuous small-dose aprotinin controls fibrinolysis during orthotopic liver transplantation

Large doses of aprotinin (1,000,000-2,000,000 kallikrein inhibitor units [KIU] initial dose and a 500,000 KIU/h infusion) have been used during orthotopic liver transplantation (OLT) to reduce the incidence and severity of fibrinolysis. This double-blinded study was designed to investigate whether a small-dose infusion of aprotinin (200,000 KIU/h) would control fibrinolysis. A controlled study was undertaken to compare small-dose aprotinin with a placebo in patients undergoing OLT with veno-venous bypass. Forty-four patients were randomized either to the aprotinin group (n = 21), which received an intravenous infusion of 200,000 KIU/h without an initial dose, or to a control group (n = 23), which received normal saline. Coagulation variables, thrombelastograms, and postoperative blood drainage were measured. Blood levels of fibrin degradation products (FDP) were significantly higher in the control group (95% > 20 micrograms/mL) at the end of surgery compared to the aprotinin group (53% > 20 micrograms/mL, P < 0.01). The transfusion of cryoprecipitate units was more in the control group versus the aprotinin (12.6 +/- 12.8 vs 5.7 +/- 7.5; P < 0.04), as was the number of fresh frozen plasma units (6.6 +/- 3.5 vs 3.6 +/- 6.1; P < 0.05). We conclude that an infusion of a small dose of aprotinin can safely control fibrinolysis during liver transplantation with a concomitant reduction in transfusion of blood products.