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Humans are exposed to environmental and economic threats that can profoundly affect individual survival and group functioning. Although anecdotal evidence suggests that threat exposure can increase collective action, the effects of threat on decision-making have been mainly investigated at the individual level. Here we examine how threat exposure and concomitant physiological responses modulate cooperation in small groups. Individuals (N = 105, ages 18–34 years) in groups of three were exposed to threat of electric shocks while deciding how much to contribute to a public good. Threat of shock induced a state of physiological freezing and, compared with no-threat conditions, reduced free riding and enabled groups to maintain higher cooperation over time. Exploratory analyses revealed that more cooperative responses under threat were driven by stronger baseline prosociality, suggesting that habitual prosociality is reinforced under threat. The current results support the view that human groups respond to outside threat with increased cooperation.

Emotion affects the way we perceive visual information. For example, if you are afraid you will process coarse visual information better and fine grained information worse than when you are in a safe state (Lojowska et al., 2015). Such threat-related bias in visual perception has been proposed to help us quickly localize threat in the environment without taking too much time for processing of the details. For example, rapid spotting of a lion in the wild is more important than to analyze its specific characteristics. Threat-related changes in perception of coarse (low-spatial frequency information, LSF) and fine (high-spatial frequency information, HSF) has been been investigated in the lab using an orientation discrimination task with Gabor gratings. During an anticipatory threat state (when individuals may receive electric shocks to their fingers), discrimination of LSF gratings improves whereas performance for HSF gratings declines (Bocanegra & Zeelenberg, 2009; Lojowska et al., 2015). At the neural level, this behavior can be explained by the difference in processing of visual information via the magnocellular and parvocellular pathways. The magnocellular pathway is responsible for processing coarse, LSF visual information necessary for rapid localization of the stimuli, whereas the parvocellular pathway is responsible for processing fine-grained, HSF information need for object recognition (Goodale & Westwood, 2004; Maunsell, 1987). LSF information can be processed via the direct subcortical magnocellular visual pathway (from retina to superior colliculus and pulvinar, that show direct connections with the amygdala, and involved emotion processing, Öhman, 2005), or in the visual cortex (though magnocellular connections from retina to LGN, lateral geniculate nucleus, to the visual cortices showing rich connections with the amygdala). Thee subcortical pathway has been proposed to be involved in automatic detection of threatening information, irrespective of any ongoing goals or tasks (LeDoux, 2000). Indeed, previous studies provided evidence that this pathway is functionally involved in the processing of LSF threat information and in the absence of visual awareness (Vuilleumier et al., 2005). Also recent study in which LSF information was perceived better under threat (Lojowska et al., 2019), supports the view that LSF information can be processed automatically and possibly via the subcortical pathway . However, to what extent the subcortical pathway is automatic and operates independently of cortical processes is still under debate (Pessoa & Adolphs, 2010; de Gelder et al., 2011). The aim of the current study is to provide further evidence that coarse visual information under threat can be processed automatically, i.e., irrespective of any ongoing tasks or goals. To this end, we will use a visual discrimination task with LSF and HSF gratings, during which we will manipulate visual working memory load (as in Vogel et al., 2001). It is known that visual memory recruit similar cortical areas as visual perception (Slotnick, 2004). If enhanced processing of LSF under threat takes place irrespective of the ongoing task and cognitive load, this effect should be observed in the presence of high visual working memory load. If the enhanced processing of LSF under threat is not automatic, this effect should disappear in the conditions of high vs. low working memory load.

Many threatening situations such as climate change require cooperation, i.e., compromising individual interests for the sake of collective benefits (Hauser, Rand, Peysakhovich, & Nowak, 2014; M. Milinski, Semmann, Krambeck, & Marotzke, 2006). Yet, maintaining cooperation in groups is challenging, since free-riding allows to reap the benefits of cooperation without paying its cost. A recent study has shown that exposure to acute threat can mitigate the break-down of cooperation in groups (Lojowska, Gross, & De Dreu, 2022). Another common mechanism that can be used to maintain cooperation and reduce free-riding is peer-punishment (Fehr & Gachter, 2002). Although successful at promoting cooperative efforts, peer-punishment can undermine the welfare of groups and reduce the total gains from cooperation. The purpose of the current study was to examine to which degree anticipatory threat can act as a substitute for costly punishment and maintain cooperation without the need to costly enforce it.

Under threat, animals tend to stick together as demonstrated by their tendency to create groups during an exposure to predators (e.g. Ioannou 2017). In humans, this ‘safety in numbers’ principle has been demonstrated in terms of increased physical proximity with the others under collective threats (e.g., staying close to each other during emergency situations, choosing larger vs. smaller groups when exposed to danger). This grouping behavior is thought to represent an evolutionarily preserved mechanism where the social context can help to facilitate threat avoidance (e.g., the chance of being attacked by a predator in a group of N individuals is equal to 1/N). However, the ‘safety in numbers’ mechanism under threat could operate not only at the level of physical proximity, but also at the level of decision making. An exposure to threat can increase individual tendency to align their decisions to what (the majority of) the group is doing, or norms. Following the norms – similar to increase in physical proximity - may increase a perception of belonging to the group under threat, and increase a subjective feeling of safety and expected support from the alike individuals. This is relevant since many societal problems (such as climate change) require a change in normative behaviors (such as eating meat), and sticking more to normative behaviors under stress may hamper this transition. Furthermore, previous studies have found that stress facilitate prosocial behaviour in the lab (e.g., Lojowska et al., 2022). Some theories have proposed, however, that social normal are imported to the lab and reflected in decisions in economic games, such as public goods game. Measuring how stress influence adherence so the rules and social norms can therefore shed more light on whether threat-induced increase in social behaviour represent the enhancement in social norms (prosociality in western societies) or indeed a shift in individual prosocial tendencies.

Description: When we are under conditions of potential threat, cognitive processes important for its detection and avoidance, such as attention and perception, improve (Ohman, Flykt, & Esteves, 2001). For example, previous research has shown that visual spatial attention is enhanced when monetary loss (punishment) depends on task performance (Engelmann & Pessoa, 2009; 2014). In their study, perceptual sensitivity (measured with signal detection, d’) was increased in a spatial cueing task due to monetary incentive. Specifically, a peripheral cue captured attention after which a target stimulus was presented at the cued location (orienting) or the opposite location (re-orienting of attention). Both orienting and re-orienting, with a stronger effect for re-orienting of spatial attention, was improved when losing (or winning) the money was dependent on the participants’ performance (relative to no incentives). This study supports the view that improvement in attention is an evolutionarily mechanism that helps us to avoid aversive cues (Ohman et al., 2001; Öhman & Wiens, 2002). However, in many situations, our behavior may benefit not only ourselves, but also others. Previous studies have demonstrated, that people are in fact more sensitive and willing to sacrifice more when it comes to the avoidance of threat to the others compared to oneself. For example, participants were willing to pay more money to grant safety (no shocks) for the other participant (stranger) than for themselves (Crockett, Kurth-Nelson, Siegel, Dayan, & Dolan, 2015). This is especially the case when threats are immediate (Vieira, Schellhaas, Enstrom, & Olsson, 2020). In addition to this explicit bias in decision making, people show an implicit tendency to perform better when the safety of others depend on it. For example, in an implicit learning task, participants demonstrated a better discrimination of aversive and safe cues when the safety of others depended on it (Lengersdorff, Wagner, Lockwood, & Lamm, 2020). These results suggest that people are willing to help others avoid threat, even at their own cost, and that this process is associated with enhanced cognitive performance. In the current study, we will investigate whether attention improves when the safety of others depends on it. We will use an exogenous spatial cueing task that measures automatic shifts of attention independent of top-down control (Posner & Cohen, 1984) . References: Crockett, M. J., Kurth-Nelson, Z., Siegel, J. Z., Dayan, P., & Dolan, R. J. (2015). Harm to others outweighs harm to self in moral decision making. Proc Natl Acad Sci U S A, 112(4), E381. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/25572965. doi:10.1073/pnas.1424572112 Lengersdorff, L. L., Wagner, I. C., Lockwood, P. L., & Lamm, C. (2020). When Implicit Prosociality Trumps Selfishness: The Neural Valuation System Underpins More Optimal Choices When Learning to Avoid Harm to Others Than to Oneself. J Neurosci, 40(38), 7286-7299. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/32839234. doi:10.1523/JNEUROSCI.0842-20.2020 Ohman, A., Flykt, A., & Esteves, F. (2001). Emotion drives attention: detecting the snake in the grass. J Exp Psychol Gen, 130(3), 466-478. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/11561921. doi:10.1037//0096-3445.130.3.466 Öhman, A., & Wiens, S. (2002). On the automaticity of autonomic responses in emotion: an evolutionary perspective. In: Davidson, R.J., Scherer, K., Hill, H.H. (Eds.). Handbook of affective sciences. Oxford University Press, New York., 256–275. Vieira, J. B., Schellhaas, S., Enstrom, E., & Olsson, A. (2020). Help or flight? Increased threat imminence promotes defensive helping in humans. Proc Biol Sci, 287(1933), 20201473. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/32842931. doi:10.1098/rspb.2020.1473

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Supplemental material, sj-docx-1-pss-10.1177_09567976221104037 for Anticipatory Threat Mitigates the Breakdown of Group Cooperation by Maria Lojowska, Jörg Gross and Carsten K. W. De Dreu in Psychological Science