Getting along
Michael Poulin, Alison Holman & Anneke Buffone
Psychological Science, forthcoming
Abstract:
Oxytocin, vasopressin, and their receptor genes influence prosocial behavior in the laboratory and in the context of close relationships. These peptides may also promote social engagement following threat. However, the scope of their prosocial effects is unknown. We examined oxytocin receptor (OXTR) polymorphism rs53576, as well as vasopressin receptor 1a (AVPR1a) polymorphisms rs1 and rs3 in a national sample of U.S. residents (n = 348). These polymorphisms interacted with perceived threat to predict engagement in volunteer work or charitable activities and commitment to civic duty. Specifically, greater perceived threat predicted engagement in fewer charitable activities for individuals with A/A and A/G genotypes of OXTR rs53576, but not for G/G individuals. Similarly, greater perceived threat predicted lower commitment to civic duty for individuals with one or two short alleles for AVPR1a rs1, but not for individuals with only long alleles. Oxytocin, vasopressin, and their receptor genes may significantly influence prosocial behavior and may lie at the core of the caregiving behavioral system.
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Joanne Powell et al.
Proceedings of the Royal Society: Biological Sciences, forthcoming
Abstract:
The social brain hypothesis, an explanation for the unusually large brains of primates, posits that the size of social group typical of a species is directly related to the volume of its neocortex. To test whether this hypothesis also applies at the within-species level, we applied the Cavalieri method of stereology in conjunction with point counting on magnetic resonance images to determine the volume of prefrontal cortex (PFC) subfields, including dorsal and orbital regions. Path analysis in a sample of 40 healthy adult humans revealed a significant linear relationship between orbital (but not dorsal) PFC volume and the size of subjects' social networks that was mediated by individual intentionality (mentalizing) competences. The results support the social brain hypothesis by indicating a relationship between PFC volume and social network size that applies within species, and, more importantly, indicates that the relationship is mediated by social cognitive skills.
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Too Fatigued to Care: Ego Depletion, Guilt, and Prosocial Behavior
Hanyi Xu, Laurent Bègue & Brad Bushman
Journal of Experimental Social Psychology, forthcoming
Abstract:
Although guilt feels bad to the individual, it is good for society because guilty feelings can prompt people to perform good deeds. This study tests whether fatigue decreases guilty feelings and subsequent prosocial behavior. Participants were randomly assigned to a depletion condition in which they watched a movie about butchering animals for their meat or skin and were told to express no emotions, or to a no-depletion condition in which they watched the same movie, but could express their emotions. Having participants play a game in which another person was punished for their errors induced guilt. Finally, participants played a dictator game in which they could leave money for the next participant. After the experiment, participants could also anonymously donate money to an anti-AIDS charity. The results showed that depleted participants felt less guilty than did non-depleted participants, and the less guilty participants felt the less helpful they were.
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Does Online Community Participation Foster Risky Financial Behavior?
Rui (Juliet) Zhu et al.
Journal of Marketing Research, forthcoming
Abstract:
Although consumers increasingly use online communities for various activities, little is known about how participation in them affects people's decision-making strategies. Through a series of field and laboratory studies, the authors demonstrate that participation in an online community increases people's risk-seeking tendencies in their financial decisions and behaviors. The results reveal that participation in an online community leads consumers to believe that they will receive help or support from other members should difficulties arise. Such a perception leads online community participants to make riskier financial decisions than nonparticipants. The authors also discover a boundary condition to the effect: Online community members are more risk seeking only when they have relatively strong ties with other members; when ties are weak, they exhibit similar risk preferences as nonmembers.
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The ontogeny of human prosociality: Behavioral experiments with children aged 3 to 8
Bailey House et al.
Evolution and Human Behavior, forthcoming
Abstract:
Humans regularly engage in prosocial behavior that differs strikingly from that of even our closest living relatives, the chimpanzees (Pan troglodytes). In laboratory settings, chimpanzees are indifferent when given the opportunity to deliver valued rewards to conspecifics, while even very young human children have repeatedly been shown to behave prosocially. Although this broadly suggests that prosocial behavior in chimpanzees differs from that of young human children, the methods used in prior work with children have also differed from the methods used in studies of chimpanzees in potentially crucial ways. Here we test 92 pairs of 3-8-year-old children from urban American (Los Angeles, CA, USA) schools in a face-to-face task that closely parallels tasks used previously with chimpanzees. We found that children were more prosocial than chimpanzees have previously been in similar tasks, and our results suggest that this was driven more by a desire to provide benefits to others than a preference for egalitarian outcomes. We did not find consistent evidence that older children were more prosocial than younger children, implying that younger children behaved more prosocially in the current study than in previous studies in which participants were fully anonymous. These findings strongly suggest that humans are more prosocial than chimpanzees from an early age and that anonymity influences children's prosocial behavior, particularly at the youngest ages.
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Sex differences in in-group cooperation vary dynamically with competitive conditions and outcomes
Drew Bailey et al.
Evolutionary Psychology, Winter 2012, Pages 102-119
Abstract:
Men's but not women's investment in a public goods game varied dynamically with the presence or absence of a perceived out-group. Three hundred fifty-four (167 male) young adults participated in multiple iterations of a public goods game under intergroup and individual competition conditions. Participants received feedback about whether their investments in the group were sufficient to earn a bonus to be shared among all in-group members. Results for the first trial confirm previous research in which men's but not women's investments were higher when there was a competing out-group. We extended these findings by showing that men's investment in the in-group varied dynamically by condition depending on the outcome of the previous trial: In the group condition, men, but not women, decreased spending following a win (i.e., earning an in-group bonus). In the individual condition, men, but not women, increased spending following a win. We hypothesize that these patterns reflect a male bias to calibrate their level of in-group investment such that they sacrifice only what is necessary for their group to successfully compete against a rival group.
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Oxytocin facilitates accurate perception of competition in men and kinship in women
Meytal Fischer-Shofty, Yechiel Levkovitz & Simone Shamay-Tsoory
Social Cognitive and Affective Neuroscience, forthcoming
Abstract:
Despite the dominant role of the hormone oxytocin (OT) in social behavior, little is known about the role of OT in the perception of social relationships. Furthermore, it is unclear whether there are sex differences in the way that OT affects social perception. Here, we employed a double-blind, placebo-controlled crossover design to investigate the effect of OT on accurate social perception. Following treatment, 62 participants completed the Interpersonal Perception Task, a method of assessing the accuracy of social judgments that requires identification of the relationship between people interacting in real life video clips divided into three categories: kinship, intimacy and competition. The findings suggest that OT had a general effect on improving accurate perception of social interactions. Furthermore, we show that OT also involves sex-specific characteristics. An interaction between treatment, task category and sex indicated that OT had a selective effect on improving kinship recognition in women, but not in men, whereas men's performance was improved following OT only for competition recognition. It is concluded that the gender-specific findings reported here may point to some biosocial differences in the effect of OT which may be expressed in women's tendency for communal and familial social behavior as opposed to men's tendency for competitive social behavior.
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The Cost of Status Enhancement: Performance Effects of Individuals' Status Mobility in Task Groups
Corinne Bendersky & Neha Parikh Shah
Organization Science, March/April 2012, Pages 308-322
Abstract:
Although we know that considerable benefits accrue to individuals with high social status, we do not know the performance effects of gaining or losing status in one's group over time. In two longitudinal studies, we measure the status positions of middle managers currently enrolled in a part-time MBA program at the beginning and end of their study group's life. In both samples, we compare the individual performance (course grades) of the students who gained or lost status to those who maintained high and low stable status positions in their groups. We find that higher status at the end of the group's life is associated with higher performance. We also find, however, that the performance of individuals who gain or lose status over time does not correspond to their final status positions. Instead, those who gain status - including those who eventually attain high status - perform worse than those who maintain high-status positions for the whole quarter. They perform no better than those in stable low-status positions throughout. Those who lose status over time actually perform as well as those who maintain high status. We interpret these results to suggest that people might trade off resources they could apply to individual performance for opportunities to enhance their status. After replicating this effect in our second sample, we identify overinvestment in increasing assertive communication and generosity as behavioral mechanisms through which individuals successfully gain status to the detriment of their own performance.
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Limited memory can be beneficial for the evolution of cooperation
Gergely Horváth, Jaromír Kovářík & Friederike Mengel
Journal of Theoretical Biology, 7 May 2012, Pages 193-205
Abstract:
In this study we analyze the effect of working memory capacity on the evolution of cooperation and show a case in which societies with strongly limited memory achieve higher levels of cooperation than societies with larger memory. Agents in our evolutionary model are arranged on a network and interact in a prisoner's dilemma with their neighbors. They learn from their own experience and that of their neighbors in the network about the past behavior of others and use this information when making their choices. Each agent can only process information from her last h interactions. We show that if memory (h) is too short, cooperation does not emerge in the long run. A slight increase of memory length to around 5-10 periods, though, can lead to largely cooperative societies. Longer memory, on the other hand, is detrimental to cooperation in our model.
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The Effects of Winning and Losing on Perceived Group Variability
Constantina Badea, Markus Brauer & Mark Rubin
Journal of Experimental Social Psychology, forthcoming
Abstract:
Previous research has shown that the people in low status, negatively-valued groups are perceived to be more homogeneous than the people in high status, positively-valued groups. The present research investigated the possibility of an opposite effect in which people perceive positive groups to be more homogeneous than negative groups. The researchers hypothesized that winning groups would be perceived to be more homogenous than losing groups because group homogeneity is associated with group cohesiveness, and group cohesiveness has a positive value in the context of an intergroup competition. In a first experiment (N = 175), target groups varied according to their objective group variability and whether they won or lost a competition. As predicted, winning groups were perceived to be significantly more homogenous than losing groups regardless of their objective variability. In a second experiment (N = 186), these effects were replicated using different social groups, and the effect of group performance on homogeneity judgements was mediated by perceptions of group cohesiveness.
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Guilty Feelings, Targeted Actions
Cynthia Cryder, Stephen Springer & Carey Morewedge
Personality and Social Psychology Bulletin, forthcoming
Abstract:
Early investigations of guilt cast it as an emotion that prompts broad reparative behaviors that help guilty individuals feel better about themselves or about their transgressions. The current investigation found support for a more recent representation of guilt as an emotion designed to identify and correct specific social offenses. Across five experiments, guilt influenced behavior in a targeted and strategic way. Guilt prompted participants to share resources more generously with others, but only did so when those others were persons whom the participant had wronged and only when those wronged individuals could notice the gesture. Rather than trigger broad reparative behaviors that remediate one's general reputation or self-perception, guilt triggers targeted behaviors intended to remediate specific social transgressions.
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James Rilling et al.
Psychoneuroendocrinology, April 2012, Pages 447-461
Abstract:
The neural mechanisms supporting social bonds between adult men remain uncertain. In this double-blind, placebo-controlled study, we investigate the impact of intranasally administered oxytocin (OT) and vasopressin (AVP) on behavior and brain activity among men in the context of an iterated Prisoner's Dilemma game, which models a real-life social situation. fMRI results show that, relative to both AVP and placebo, OT increases the caudate nucleus response to reciprocated cooperation, which may augment the reward of reciprocated cooperation and/or facilitate learning that another person can be trusted. OT also enhances left amygdala activation in response to reciprocated cooperation. Behaviorally, OT was associated with increased rates of cooperation following unreciprocated cooperation in the previous round compared with AVP. AVP strongly increased cooperation in response to a cooperative gesture by the partner compared with both placebo and OT. In response to reciprocated cooperation, AVP increased activation in a region spanning known vasopressin circuitry implicated in affiliative behaviors in other species. Finally, both OT and AVP increase amygdala functional connectivity with the anterior insula relative to placebo, which may increase the amygdala's ability to elicit visceral somatic markers that guide decision making. These findings extend our knowledge of the neural and behavioral effects of OT and AVP to the context of genuine social interactions.
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Alexa Veenema
Hormones and Behavior, March 2012, Pages 304-312
Abstract:
The early-life social environment has profound effects on brain development and subsequent expression of social behavior. Oxytocin and vasopressin are expressed and released in the brain and are important regulators of social behavior. Accordingly, the early social environment may alter social behaviors via changes in the oxytocin and/or vasopressin systems. To test this hypothesis, and to gain mechanistic insights, rodent models mimicking either a deprived (e.g. maternal separation) or enriched (e.g. neonatal handling) early social environment have been utilized. Findings indeed show that differences in the quality of the early social environment are associated with brain region-specific alterations in oxytocin and vasopressin expression and oxytocin receptor and vasopressin 1a receptor binding. Early social environment-induced changes in oxytocin and vasopressin systems were associated with changes in several forms of social behavior, including maternal care, aggression, play-fighting, and social recognition. First studies provide evidence for a causal link between altered vasopressin responsiveness and impairments in social recognition in rats exposed to maternal separation and a role for epigenetic mechanisms to explain persistent increases in vasopressin expression in mice exposed to maternal separation. Overall, initial findings suggest that oxytocin and vasopressin systems may mediate early social environment-induced alterations in social behavior. Additional comprehensive studies will be necessary to advance our understanding to what extent changes in oxytocin and vasopressin underlie early social environment-induced alterations in social behavior.
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Jie Chen et al.
Neuroscience Letters, forthcoming
Abstract:
The present study investigated the temporal features of processing facial attractiveness, and its influence on the subsequent cooperative behavior. Event-related potentials (ERPs) were recorded for both face stimuli (attractive or unattractive faces) and feedback stimuli (loss or gain) while participants performed a modified trust game task, in which participants decided whether to cooperate with fictional partners (attractive or unattractive faces) for a chance to earn monetary rewards; feedback (loss or gain) were presented after their decisions. The behavioral results showed that participants were more likely to cooperate with the attractive partners than with the unattractive partners. The ERP analysis for face stimuli showed that a smaller P2 amplitude was elicited by attractive faces compared to unattractive faces. In addition, attractive faces elicited larger N2 and smaller late positive component (LPC) amplitudes than unattractive faces. More interestingly, a larger feedback related negativity (FRN) was elicited within the attractive face condition compared with the unattractive face condition. Therefore, our findings demonstrate that the discrimination of attractive and unattractive faces occurs at the early P2 stage, reflecting automatic processing of facial attractiveness. Moreover, the present study further demonstrates that facial attractiveness facilitates cooperative behavior, and that FRN elicited by outcome stimuli might be used as an index of how people judge and predict another's behavior in a social game.