Research investigating collective decision making has focused primarily on the improvement of accuracy in collective decisions and less on the motives that drive individuals to make these decisions. We argue that a strong but neglected motive for making collective decisions is minimizing the material and psychological burden of an individual’s responsibility. Making difficult decisions with others shields individuals from the consequences of negative outcomes by reducing regret, punishment, and stress. Considering shared responsibility as a another key motivation to join groups helps understand behaviors with societal implications such as political voting, committing norm violations, predicting natural disasters, and making health-related decisions.

Efficient detection and reaction to negative signals in the environment is essential for survival. In social situations, these signals are often ambiguous and can imply different levels of threat for the observer, thereby making their recognition susceptible to contextual cues – such as gaze direction when judging facial displays of emotion. However, the mechanisms underlying such contextual effects remain poorly understood. By computational modeling of human behavior and electrical brain activity, we demonstrate that gaze direction enhances the perceptual sensitivity to threat-signaling emotions – anger paired with direct gaze, and fear paired with averted gaze. This effect arises simultaneously in ventral face-selective and dorsal motor cortices at 200 ms following face presentation, dissociates across individuals as a function of anxiety, and does not reflect increased attention to threat-signaling emotions. These findings reveal that threat tunes neural processing in fast, selective, yet attention-independent fashion in sensory and motor systems, for different adaptive purposes.DOI: http://dx.doi.org/10.7554/eLife.10274.001

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With restricted face-to-face interactions, COVID-19 lockdowns and distancing measures tested the capability of computer-mediated communication to foster social contact and wellbeing. In a multinational sample ( n = 6436), we investigated how different modes of contact related to wellbeing during the pandemic. Computer-mediated communication was more common than face-to-face, and its use was influenced by COVID-19 death rates, more so than state stringency measures. Despite its legal and health threats, face-to-face contact was still positively associated with wellbeing, and messaging apps had a negative association. Perceived household vulnerability to COVID-19 reduced the positive effect of face-to-face communication on wellbeing, but surprisingly, people’s own vulnerability did not. Computer-mediated communication was particularly negatively associated with the wellbeing of young and empathetic people. Findings show people endeavored to remain socially connected, yet however, maintain a physical distance, despite the tangible costs to their wellbeing.

Chronometric properties of theory of mind and intentions understanding more specifically are well documented. Notably, it was demonstrated using magnetoencephalography that the brain regions involved were recruited as soon as 200 ms post-stimulus. We used event-related potentials (ERPs) to characterize an electrophysiological marker of attribution of intentions. We also explored the robustness of this ERP signature under two conditions corresponding to either explicit instructions to focus on others' intentions or implicit instructions with no reference to mental states. Two matched groups of 16 healthy volunteers each received either explicit or no instructions about intentions and performed a nonverbal attribution of intentions task based on sequential four-image comic strips depicting either intentional or physical causality. A bilateral posterior positive component, ranging from 250 to 650 ms post-stimulus, showed greater amplitude in intentional than in physical condition (the intention ERP effect). This effect occurs during the third image only, suggesting that it reflects the integration of information depicted in the third image to the contextual cues given by the first two. The intention effect was similar in the two groups of subjects. Overall, our results identify a clear ERP marker of the first hundreds of milliseconds of intentions processing probably related to a contextual integrative mechanism and suggest its robustness by showing its blindness to task demands manipulation.

It has recently been proposed that a key motivation for joining groups is the protection from the negative consequences of undesirable outcomes. To test this claim, we investigated how experienced outcomes triggering loss and regret impacted people's tendency to decide alone or join a group, and how decisions differed when voluntarily made alone versus in group. Replicated across two experiments, participants ( n = 125 and n = 496) selected whether to play alone or contribute their vote to a group decision. Next, they chose between two lotteries with different probabilities of winning and losing. The higher the negative outcome, the more participants switched from deciding alone to with others. When joining a group to choose the lottery, choices were less driven by outcome and regret anticipation. Moreover, negative outcomes experienced alone, not part of a group vote, led to worse subsequent choices than positive outcomes. These results suggest that the protective shield of the collective reduces the influence of negative emotions that may help individuals re-evaluate past choices.

Humans combine co-emitted social signals to predict other's immediate intentions and prepare an adapted response. However, little is known about whether attending to only one of co-emitted social signals impacts on its combination with other signals. Here, using electroencephalography, we address selective attention effects on early combination of social signals. We manipulated three visual cues: gaze direction, emotional expression, and pointing gesture, while participants performed either emotion or gaze direction judgments. Results showed that a temporal marker of social cues integration emerges 170 ms after the stimulus onset, even if the integration of the three visual cues was not required to perform the task, as only one feature at a time was task-relevant. Yet, in addition to common temporal regions, the relative contribution of specific neural sources of this integration changed as a function of the attended feature: integration during emotion judgments was mainly implemented in classical limbic areas but in the dorsal pathway during gaze direction judgments.Together, these findings demonstrate that co-emitted social cues are integrated as long as they are relevant to the observer, even when they are irrelevant to the ongoing task.

Background: It has recently been proposed that a key motivation for joining groups is the protection from consequences of negative behaviours, such as norm violations. Here we empirically test this claim by investigating whether cooperative decisions and the punishment of associated fairness-based norm violations are different in individuals vs. collectives in economic games. Methods: In the ultimatum game, participants made or received offers that they could reject at a cost to their outcome, a form of social punishment. In the dictator game with third-party punishment, participants made offers to a receiver while being observed by a punisher, or could themselves punish unfair offers. Results: Participants made lower offers when making their decision as part of a group as compared to alone. This difference correlated with participants’ overall mean offers: those who were generally less generous were even less so in a group, suggesting that the collective structure was compatible with their intention. Participants were slower when punishing vs not punishing an unfair offer. Importantly here, they were slower when deciding whether to punish or not to punish groups as compared to individuals, only when the offer concerned them directly in second party punishment. Participants thus take more time to punish others, and to make their mind on whether to punish or not when facing a group of proposers. Conclusions: Together, these results show that people behave differently in a group, both in their willingness to share with others and in their punishment of norm violations. This could be explained by the fact that being in a collective structure allows to share responsibility with others, thereby protecting from negative consequences of norm violations.