Neural signatures of prosocial behaviors

Empathy incites a stable prosocial decision bias

Empathy toward suffering individuals serves as potent driver for prosocial behavior. However, it remains unclear whether prosociality induced by empathy for another person's pain persists once that person's suffering diminishes. To test this, participants underwent functional magnetic resonance imaging while performing a binary social decision task that involved allocation of points to themselves and another person. In block one, participants completed the task after witnessing frequent painful stimulation of the other person, and in block two, after observing low frequency of painful stimulation. Drift-diffusion modeling revealed an increased initial bias toward making prosocial decisions in the first block compared with baseline that persisted in the second block. These results were replicated in an independent behavioral study. An additional control study showed that this effect may be specific to empathy as stability was not evident when prosocial decisions were driven by a social norm such as reciprocity. Increased neural activation in dorsomedial prefrontal cortex was linked to empathic concern after witnessing frequent pain and to a general prosocial decision bias after witnessing rare pain. Altogether, our findings show that empathy for pain elicits a stable inclination toward making prosocial decisions even as their suffering diminishes.

Age-related changes in ventrolateral prefrontal cortex activation are associated with daily prosocial behaviors two years later

As adolescents acquire agency and become contributing members of society, it is necessary to understand how they help their community. Yet, it is unknown how prosocial behavior develops in the context of community-based prosocial behaviors that are relevant to adolescents, such as donating time to charities. In this longitudinal functional magnetic resonance imaging study, adolescents (N=172; mean age at wave 1=12.8) completed a prosocial task annually for three years (N=422 and 375 total behavioral and neural data points, respectively), and 14 days of daily diaries reporting on their prosocial behaviors two years later. During the task, adolescents decided how many minutes they would donate to a variety of local charities. We found that adolescents donated less time to charities from early to mid adolescence. Longitudinal whole-brain analyses revealed declines in ventrolateral prefrontal cortex (vlPFC) activation, as well as inverted U-shaped changes in precuneus activation when adolescents donated their time from early to mid adolescence. A less steep decrease in vlPFC activation predicted greater real-life prosocial behaviors in youth's daily lives two years later. Our study elucidates the neurodevelopmental mechanisms of prosocial behavior from early to mid adolescence that have enduring effects on daily prosocial behaviors in late adolescence.

The effect of autistic traits on prosocial behavior: The chain mediating role of received social support and perceived social support

ABSTRACT

There is growing evidence that the defining characteristics of autism spectrum disorder are distributed across the general population; therefore, understanding the correlates of prosocial behavior in individuals with high levels of autistic traits could shed light on autism spectrum disorder and prosocial behavior. In this study, the mechanism underlying the influence of individuals’ autistic traits on their prosocial behavior was explored by conducting a questionnaire survey of 414 Chinese college students. The results showed that autistic traits can influence individuals’ prosocial behavior not only through the separate effects of received social support and perceived social support but also through the chain mediating effects of received social support and perceived social support; however, the direct effect of autistic traits on individuals’ prosocial behavior is not significant. This study is conducive to understanding the internal mechanism underlying the relationship between autistic traits and prosocial behavior. Future work is required to further investigate the clinical autism spectrum disorder samples and cross-cultural applicability of the model found in this study.

The links between physical activity and prosocial behavior: an fNIRS hyperscanning study

The prevalence of physically inactive lifestyles in modern society raises concerns about the potential association with poor brain health, particularly in the lateral prefrontal cortex, which is crucial for human prosocial behavior. Here, we explored the relationship between physical activity and prosocial behavior, focusing on potential neural markers, including intra-brain functional connectivity and inter-brain synchrony in the lateral prefrontal cortex. Forty participants, each paired with a stranger, completed two experimental conditions in a randomized order: (i) face-to-face and (ii) face stimulus (eye-to-eye contact with a face stimulus of a fictitious person displayed on the screen). Following each condition, participants played economic games with either their partner or an assumed person displayed on the screen. Neural activity in the lateral prefrontal cortex was recorded by functional near-infrared spectroscopy hyperscanning. Sparse multiset canonical correlation analysis showed that a physically inactive lifestyle was covaried with poorer reciprocity, greater trust, shorter decision-making time, and weaker intra-brain connectivity in the dorsal lateral prefrontal cortex and poorer inter-brain synchrony in the ventral lateral prefrontal cortex. These associations were observed exclusively in the face-to-face condition. Our findings suggest that a physically inactive lifestyle may alter human prosocial behavior by impairing adaptable prosocial decision-making in response to social factors through altered intra-brain functional connectivity and inter-brain synchrony.

Disrupting the Dorsolateral Prefrontal Cortex Attenuates the Difference in Decision-Making for Altruistic Punishment Between the Gain and Loss Contexts

Altruistic punishment is a primary response to social norms violations; its neural mechanism has also attracted extensive research attention. In the present studies, we applied a low-frequency repetitive transcranial magnetic stimulation (rTMS) to the bilateral dorsolateral prefrontal cortex (DLPFC) while participants engaged in a modified Ultimatum Game (Study 1) and third-party punishment game (Study 2) to explore how the bilateral DLPFC disruption affects people's perception of violation of fairness norms and altruistic punishment decision in the gain and loss contexts. Typically, punishers intervene more often against and show more social outrage towards Dictators/Proposers who unfairly distribute losses than those who unfairly share gains. We found that disrupting the function of the left DLPFC in the second-party punishment and the bilateral DLPFC in the third-party punishment with rTMS effectively obliterated this difference, making participants punish unfairly shared gains as often as they usually would punish unfairly shared losses. In the altruistic punishment of maintaining the social fairness norms, the inhibition of the right DLPFC function will affect the deviation of individual information integration ability; the inhibition of the left DLPFC function will affect the assessment of the degree of violation of fairness norms and weaken impulse control, leading to attenuate the moderating effect of gain and loss contexts on altruistic punishment. Our findings emphasize that DLPFC is closely related to altruistic punishment and provide causal neuroscientific evidence.

Acute stress reduces effortful prosocial behaviour

Acute stress can change our cognition and emotions, but what specific consequences this has for human prosocial behaviour is unclear. Previous studies have mainly investigated prosociality with financial transfers in economic games and produced conflicting results. Yet a core feature of many types of prosocial behaviour is that they are effortful. We therefore examined how acute stress changes our willingness to exert effort that benefits others. Healthy male participants - half of whom were put under acute stress - made decisions whether to exert physical effort to gain money for themselves or another person. With this design, we could independently assess the effects of acute stress on prosocial, compared to self-benefitting, effortful behaviour. Compared to controls (n = 45), participants in the stress group (n = 46) chose to exert effort more often for self- than for other-benefitting rewards at a low level of effort. Additionally, the adverse effects of stress on prosocial effort were particularly pronounced in more selfish participants. Neuroimaging combined with computational modelling revealed a putative neural mechanism underlying these effects: more stressed participants showed increased activation to subjective value in the dorsal anterior cingulate cortex and anterior insula when they themselves could benefit from their exerted effort relative to when someone else could. By using an effort-based task that better approximates real-life prosocial behaviour and incorporating trait differences in prosocial tendencies, our study provides important insights into how acute stress affects prosociality and its associated neural mechanisms.

Prosocial decision-making under time pressure: Behavioral and neural mechanisms

The present study employed a novel paradigm and functional magnetic resonance imaging (fMRI) to uncover the specific regulatory mechanism of time pressure and empathy trait in prosocial decision-making, compared to self-decision making. Participants were instructed to decide whether to spend their own monetary interest to alleviate themselves (or another person) from unpleasant noise threats under high and low time pressures. On the behavioral level, results showed that high time pressure had a significant effect on reducing participants' willingness to spend money on relieving themselves from the noise, while there is a similar but not significant trend in prosocial decision-making. On the neural level, for self-concerned decision-making, low time pressure activated the bilateral insula more strongly than high time pressure. For prosocial decision-making, high time pressure suppressed activations in multiple brain regions related to empathy (temporal pole, middle temporal gyrus, and inferior frontal gyrus), valuation (medial orbitofrontal cortex), and emotion (putamen). The functional connectivity strength among these regions, especially the connectivity between the medial orbitofrontal cortex and putamen, significantly predicted the effect of time pressure on prosocial decision-making at the behavioral level. Additionally, we discovered the activation of the medial orbitofrontal cortex partially mediated the effect of empathy trait scores on prosocial decision-making. These findings suggest that (1) there are different neural underpinnings for the modulation of time pressure for self and prosocial decision-making, and (2) the empathy trait plays a crucial role in the latter.

Higher subjective socioeconomic status is linked to increased charitable giving and mentalizing-related neural value coding

Socioeconomic status (SES), a concept related to an individual's economic and social position relative to others, can shape social interactions like altruistic behaviors. However, little is known about the exact neurocognitive mechanisms that link SES with altruism. Our study aimed to provide a comprehensive account of the sociocognitive and neural mechanisms through which SES affects charitable giving - an important variant of human altruism. To this end, participants completed a charitable donation task while their brain activity was measured using functional magnetic resonance imaging (fMRI). We also assessed participants' socio-cognitive ability to infer other people's mental states (i.e., mentalizing) - a driver of prosocial behavior - in an independent social task. Behaviorally, we found that both charitable giving and social cognition were status-dependent, as subjective SES positively predicted donations and mentalizing capacity. Moreover, the link between SES and charitable giving was mediated by individuals' mentalizing capacity. At the neural level, a multivariate pattern analysis of fMRI data revealed that higher subjective SES was associated with stronger value coding in the right temporoparietal junction (rTPJ). The strength of this value representation predicted charitable giving and was linked to mentalizing. Furthermore, we observed an increased negative functional coupling between rTPJ and left putamen with higher SES. Together, increased charitable giving in higher-status individuals could be explained by status-dependent recruitment of mentalizing-related value coding and altered functional connectivity in the brain. Our findings provide insights into the socio- and neurocognitive mechanisms explaining why and when higher SES leads to prosociality, which might ultimately inform targeted interventions to promote prosocial behavior in human societies.

The influence of altruistic personality, interpersonal distance and social observation on prosocial behavior: An event-related potential (ERP) study

The psychological mechanisms that high and low altruists exhibit in different contexts remain unknown. This study examined the underlying mechanisms of the effect of altruistic personality, social observation, and interpersonal distance on prosocial behavior using event-related potentials (ERPs). Participants with high and low altruism were asked to make prosocial or non-prosocial choices toward different interpersonal distances (friends, acquaintances, or strangers) under the (non)observer condition. The electrophysiological responses to the choice stimuli were simultaneously recorded. The behavioral results demonstrated that high altruists had more prosocial choices, and these choices were unaffected by interpersonal distance and social observation. However, low altruists made more prosocial choices toward friends and acquaintances under the observer than nonobserver conditions, whereas their prosocial choices toward strangers showed no difference. The ERP results demonstrated that low altruists showed more negative N2 when the choice stimuli were toward strangers and acquaintances or under the nonobserver condition. Furthermore, low altruists showed larger P3 under the observer than nonobserver conditions when the choice stimuli were toward friends and acquaintances, while this difference was absent when the choice stimuli were toward strangers. However, for high altruists, no effect of interpersonal distance and social observation was observed in N2 and P3. These results suggest that the prosocial behavior of low altruists is mainly driven by reputational incentives, whereas high altruists are primarily motivated by concern about the well-being of others. Our findings provide insights into the prosocial behavior of high and low altruists in different contexts and support the empathy-altruism hypothesis.

Neural Representation of Donating Time and Money

Volunteering and charitable donations are two common forms of prosocial behavior, yet it is unclear whether these other-benefitting behaviors are supported by the same or different neurobiological mechanisms. During an fMRI task, 40 participants (20 female-identifying; age: mean = 18.92 years, range = 18.32-19.92 years) contributed their time (in minutes) and money (in dollars) to a variety of local charities. With the maximum amount of time and money that participants could spend on these charities, they did not differentially donate their time and money. At the neural level, donating time and money both showed activations in brain regions involved in cognitive control (e.g., dorsolateral PFC) and affective processing (e.g., dorsal anterior cingulate cortex), but donating time recruited regions involved in reward valuation (e.g., ventral striatum) and mentalizing (e.g., temporal pole) to a greater extent than donating money. Further, the precuneus, which is also a region involved in mentalizing, more strongly tracked the varying amount of money than time donated, suggesting that the precuneus may be more sensitive to the increasing magnitude of a nonsocial exchange (e.g., donating money is a financial exchange) than a social exchange (e.g., donating time is an interpersonal exchange). Our findings elucidate shared as well as distinct neurobiological properties of two prosocial behaviors, which have implications for how humans share different resources to positively impact their community.SIGNIFICANCE STATEMENT Prosocial behaviors broadly characterize how humans act to benefit others. Various prosocial behaviors, such as volunteering and charitable donations, share the goal of positively contributing to community. Our study identifies brain regions that may serve as ubiquitous neurobiological markers of community-based prosocial behaviors. Despite this shared goal, our study also shows that the human brain responds to donating time and money in diverging ways, such that brain regions associated with processing emotional reward and thinking about others are more strongly recruited for donating time than for money. Therefore, our study sheds light on how different personal resources, such as one's time and money, within a prosocial context are represented in the brain.

Altered functional connectivity of the amygdala across variants of callous-unemotional traits: A resting-state fMRI study in children and adolescents

Over the past years, research has shown that primary (high callousness and low anxiety) and secondary (high callousness and anxiety) variants of CU traits may be associated with opposite amygdala activity (hypo- and hyper-reactivity, respectively). However, their differences in amygdala functional connectivity remains largely unexplored. We conducted a Latent Profile Analysis on a large sample of adolescents (n = 1416) to identify homogeneous subgroups with different levels of callousness and anxiety. We then performed a seed-to-voxel connectivity analysis on resting-state fMRI data to compare subgroups on connectivity patterns of the amygdala. We examined the results in relation to conduct problems to identify potential neural risk factors. The Latent Profile Analysis revealed four subgroups, including the primary and secondary variants, anxious, and typically developing adolescents. The seed-to-voxel analyses showed that the primary variant was mainly characterized by increased connectivity between the left amygdala and left thalamus. The secondary variant exhibited deficient connectivity between the amygdala and the dorsomedial prefrontal cortex, temporo-parietal junction, premotor, and postcentral gyrus. Both variants showed increased connectivity between the left amygdala and the right thalamus but exhibited opposite functional connectivity between the left amygdala and the parahippocampal gyrus. Dimensional analyses indicated that conduct problems may play a mediating role between callousness and amygdala-dmPFC functional connectivity across youths with already high levels of callousness. Our study highlights that both variants differ in the functional connectivity of the amygdala. Our results support the importance of disentangling the heterogeneity of adolescents at risk for conduct problems in neuroimaging.

The role of ventrolateral prefrontal cortex on voluntary emotion regulation of social pain

The right ventrolateral prefrontal cortex (rVLPFC) is highly engaged in emotion regulation of social pain. However, there is still lack of both inhibition and excitement evidence to prove the causal relationship between this brain region and voluntary emotion regulation. This study used high-frequency (10 Hz) and low-frequency (1 Hz) repetitive transcranial magnetic stimulation (rTMS) to separately activate or inhibit the rVLPFC in two groups of participants. We recorded participants' emotion ratings as well as their social attitude and prosocial behaviors following emotion regulation. Also, we used eye tracker to record the changes of pupil diameter to measure emotional feelings objectively. A total of 108 healthy participants were randomly assigned to the activated, inhibitory or sham rTMS groups. They were required to accomplish three sequential tasks: the emotion regulation (cognitive reappraisal) task, the favorability rating task, and the donation task. Results show that the rVLPFC-inhibitory group reported more negative emotions and showed larger pupil diameter while the rVLPFC-activated group showed less negative emotions and reduced pupil diameter during emotion regulation (both compared with the sham rTMS group). In addition, the activated group gave more positive social evaluation to peers and donated more money to a public welfare activity than the rVLPFC-inhibitory group, among which the change of social attitude was mediated by regulated emotion. Taken together, these findings reveal that the rVLPFC plays a causal role in voluntary emotion regulation of social pain and can be a potential brain target in treating deficits of emotion regulation in psychiatric disorders.

Threat-induced anxiety and selfishness in resource sharing: Behavioral and neural evidence

In real life, it is not unusual that we face potential threats (i.e., physical stimuli and environments that may cause harm or danger) with other individuals together, yet it remains largely unknown how threat-induced anxious feelings influence prosocial behaviors such as resource sharing. In this study, we investigated this question by combining functional magnetic resonance imaging and a novel paradigm. Together with an anonymous partner, each participant faced the possibility of receiving a 10-s noise administration, which had a low or high probability to be a threat (i.e., the intensity of noise can induce a high level of unpleasantness). Each participant first reported her/his immediate feeling of anxiety about the current situation (being threatened by the unpleasant noise), then decided how to split a number of resources (which could relieve the noise) between her/him and the partner. Behavioral results revealed that the participants showed a selfish bias in the threat conditions than in the safe conditions, and that self-reported anxiety feeling significantly predicted this bias. Functional magnetic resonance imaging results revealed that: (1) the activation level of the anterior insula was correlated with self-reported anxiety and (2) the connectivity between the anterior insula and the temporoparietal junction was sensitive to the modulating effect of anxiety on the selfish bias. These findings indicate the neural correlates of the association between threat-induced anxiety and prosocial tendencies in social interactions.

Only empathy-related traits, not being mimicked or endorphin release, influence social closeness and prosocial behavior

Seminal studies suggest that being mimicked increases experienced social closeness and prosocial behavior to a mimicking confederate (i.e., interaction partner). Here we reexamine these results by considering the role of empathy-related traits, an indirect proxy for endorphin uptake, and their combined effects as an explanation for these results. 180 female participants were mimicked or anti-mimicked in an interaction with a confederate. The effects of being mimicked versus anti-mimicked in relation to empathy-related traits and endorphin release (assessed indirectly via pain tolerance) on experienced closeness and prosocial behavior were assessed using Bayesian analyses. Our results suggest that high individual empathy-related traits increase social closeness to the anti-mimicking and mimicking confederate and to one's romantic partner, as compared to mimicry alone. Results furthermore strongly suggest that high individual empathy-related traits increase prosocial behavior (donations and willingness to help) as compared to mimicry alone. These findings extend previous work by highlighting that empathy-related traits are more influential in creating positive effects on social closeness and prosocial behavior than a one-shot mimicking encounter.

Neural bases of loss aversion when choosing for oneself versus known or unknown others

Despite the ubiquitous interdependence between one's own decisions and others' welfare, and the controversial evidence on the behavioral effect of choosing for others, the neural bases of making decisions for another versus oneself remain unexplored. We investigated whether loss aversion (LA; the tendency to avoid losses over approaching equivalent gains) is modulated by (i) choosing for oneself, other individuals, or both; (ii) knowing or not knowing the other recipients; or (iii) an interaction between these factors. We used fMRI to assess the brain activations associated with choosing whether to accept or reject mixed gambles, either for oneself, for another player, or both, in 2 groups of 28 participants who had or had not briefly interacted with the other players before scanning. Participants displayed higher LA for choices involving their payoff compared with those affecting only the payoff of other, known, players. This "social" modulation of decision-making was found to engage the dorsomedial prefrontal cortex and its inhibitory connectivity to the middle cingulate cortex. This pattern might underpin decision-making for known others via self-other distinction processes associated with dorsomedial prefrontal areas, with this in turn promoting the inhibition of socially oriented responses through the downregulation of the midcingulate node of the empathy network.

Can Translational Social Neuroscience Research Offer Insights to Mitigate Structural Racism in the United States?

Social isolation and conflict due to structural racism may result in human suffering and loneliness across the life span. Given the rising prevalence of these problems in the United States, combined with disruptions experienced during the COVID-19 pandemic, the neurobiology of affiliative behaviors may offer practical solutions to the pressing challenges associated with structural racism. Controlled experiments across species demonstrate that social connections are critical to survival, although strengthening individual resilience is insufficient to address the magnitude and impact of structural racism. In contrast, the multilevel construct of social resilience, defined by the power of groups to cultivate, engage in, and sustain positive relationships that endure and recuperate from social adversities, offers unique insights that may have greater impact, reach, and durability than individual-level interventions. Here, we review putative social resilience-enhancing interventions and, when available, their biological mediators, with the hope to stimulate discovery of novel approaches to mitigate structural racism. We first explore the social neuroscience principles underlying psychotherapy and other psychiatric interventions. Then, we explore translational efforts across species to tailor treatments that increase social resilience, with context and cultural sensitivity in mind. Finally, we conclude with some practical future directions for understudied areas that may be essential for progress in biological psychiatry, including ethical ways to increase representation in research and developing social paradigms that inform dynamics toward or away from socially resilient outcomes.

The bright and dark sides of egoism

Despite its negative reputation, egoism - the excessive concern for one's own welfare - can incite prosocial behavior. So far, however, egoism-based prosociality has received little attention. Here, we first provide an overview of the conditions under which egoism turns into a prosocial motive, review the benefits and limitations of egoism-based prosociality, and compare them with empathy-driven prosocial behavior. Second, we summarize studies investigating the neural processing of egoism-based prosocial decisions, studies investigating the neural processing of empathy-based prosocial decisions, and the small number of studies that compared the neural processing of prosocial decisions elicited by the different motives. We conclude that there is evidence for differential neural networks involved in egoism and empathy-based prosocial decisions. However, this evidence is not yet conclusive, because it is mainly based on the comparison of different experimental paradigms which may exaggerate or overshadow the effect of the different motivational states. Finally, we propose paradigms and research questions that should be tackled in future research that could help to specify how egoism can be used to enhance other prosocial behavior and motivation, and the how it could be tamed.

Sleep loss leads to the withdrawal of human helping across individuals, groups, and large-scale societies

Humans help each other. This fundamental feature of homo sapiens has been one of the most powerful forces sculpting the advent of modern civilizations. But what determines whether humans choose to help one another? Across 3 replicating studies, here, we demonstrate that sleep loss represents one previously unrecognized factor dictating whether humans choose to help each other, observed at 3 different scales (within individuals, across individuals, and across societies). First, at an individual level, 1 night of sleep loss triggers the withdrawal of help from one individual to another. Moreover, fMRI findings revealed that the withdrawal of human helping is associated with deactivation of key nodes within the social cognition brain network that facilitates prosociality. Second, at a group level, ecological night-to-night reductions in sleep across several nights predict corresponding next-day reductions in the choice to help others during day-to-day interactions. Third, at a large-scale national level, we demonstrate that 1 h of lost sleep opportunity, inflicted by the transition to Daylight Saving Time, reduces real-world altruistic helping through the act of donation giving, established through the analysis of over 3 million charitable donations. Therefore, inadequate sleep represents a significant influential force determining whether humans choose to help one another, observable across micro- and macroscopic levels of civilized interaction. The implications of this effect may be non-trivial when considering the essentiality of human helping in the maintenance of cooperative, civil society, combined with the reported decline in sufficient sleep in many first-world nations.

Giving to others and neural processing during adolescence

Adolescence is marked by an increased sensitivity to the social environment as youth navigate evolving relationships with family, friends, and communities. Prosocial behavior becomes more differentiated such that older adolescents increasingly give more to known others (e.g., family, friends) than to strangers. This differentiation may be linked with changes in neural processing among brain regions implicated in social decision-making. A total of 269 adolescents from 9–15 and 19–20 years of age completed a decision-making task in which they could give money to caregivers, friends, and strangers while undergoing functional magnetic resonance imaging (fMRI). Giving to caregivers and friends (at a cost to oneself) increased with age, but giving to strangers remained lower and stable across age. Brain regions implicated in cognitive control (dorsolateral and ventrolateral prefrontal cortex) showed increased blood-oxygen-level-dependent (BOLD) activation with increasing age across giving decisions to all recipients; regions associated with reward processing (ventral striatum and ventral tegmental area) showed increased activation across all ages when giving to all recipients. Brain regions associated with social cognition were either not active (dorsomedial prefrontal cortex) or showed reduced activation (temporal parietal junction and posterior superior temporal sulcus) when giving to others across all ages. Findings have implications for understanding the role of brain development in the increased complexity of social decision-making during adolescence.

Functional Connectivity Differences Between Two Culturally Distinct Prairie Vole Populations: Insights Into the Prosocial Network

BACKGROUND

The goal of this study was to elucidate the fundamental connectivity-resting-state connectivity-within and between nodes in the olfactory and prosocial (PS) cores, which permits the expression of social monogamy in males; and how differential connectivity accounts for differential expression of prosociality and aggression.

METHODS

Using resting-state functional magnetic resonance imaging, we integrated graph theory analysis to compare functional connectivity between two culturally/behaviorally distinct male prairie voles (Microtusochrogaster).

RESULTS

Illinois males display significantly higher levels of prosocial behavior and lower levels of aggression than KI (Kansas dam and Illinois sire) males, which are associated with differences in underlying neural mechanisms and brain microarchitecture. Shared connectivity 1) between the anterior hypothalamic area and the paraventricular nucleus and 2) between the medial preoptic area and bed nucleus of the stria terminalis and the nucleus accumbens core suggests essential relationships required for male prosocial behavior. In contrast, Illinois males displayed higher levels of global connectivity and PS intracore connectivity, a greater role for the bed nucleus of the stria terminalis and anterior hypothalamic area, which were degree connectivity hubs, and greater PS and olfactory intercore connectivity.

CONCLUSIONS

These findings suggest that behavioral differences are associated with PS core degree of connectivity and postsignal induction. This transgenerational system may serve as powerful mental health and drug abuse translational model in future studies.

Neural correlates of affective empathy in aging: A multimodal imaging and multivariate approach

Empathy is one such social-cognitive capacity that undergoes age-related change. C urrently, however, not well understood is the structural and functional neurocircuitry underlying age-related differences in empathy. This study aimed to delineate brain structural and functional networks that subserve affective empathic response in younger and older adults using a modified version of the Multifaceted Empathy Task to both positive and negative emotions. Combining multimodal neuroimaging with multivariate partial least square analysis resulted in two novel findings in older but not younger adults: (a) faster empathic responding to negative emotions was related to greater fractional anisotropy of the anterior cingulum and greater functional activity of the anterior cingulate network; (b) however, empathic responding to positive emotions was related to greater fractional anisotropy of the posterior cingulum and greater functional activity of the posterior cingulate network. Such differentiation of structural and functional networks might have critical implications for prosocial behavior and social connections among older adults.

Altruism under Stress: Cortisol Negatively Predicts Charitable Giving and Neural Value Representations Depending on Mentalizing Capacity

Altruism, defined as costly other-regarding behavior, varies considerably across people and contexts. One prominent context in which people frequently must decide on how to socially act is under stress. How does stress affect altruistic decision-making and through which neurocognitive mechanisms? To address these questions, we assessed neural activity associated with charitable giving under stress. Human participants (males and females) completed a charitable donation task before and after they underwent either a psychosocial stressor or a control manipulation, while their brain activity was measured using functional magnetic resonance imaging. As the ability to infer other people's mental states (i.e., mentalizing) predicts prosocial giving and may be susceptible to stress, we examined whether stress effects on altruism depend on participants' general capacity to mentalize, as assessed in an independent task. Although our stress manipulation per se had no influence on charitable giving, increases in the stress hormone cortisol were associated with reductions in donations in participants with high mentalizing capacity, but not in low mentalizers. Multivariate neural response patterns in the right dorsolateral prefrontal cortex (DLPFC) were less predictive of postmanipulation donations in high mentalizers with increased cortisol, indicating decreased value coding, and this effect mediated the (moderated) association between cortisol increases and reduced donations. Our findings provide novel insights into the modulation of altruistic decision-making by suggesting an impact of the stress hormone cortisol on mentalizing-related neurocognitive processes, which in turn results in decreased altruism. The DLPFC appears to play a key role in mediating this cortisol-related shift in altruism.SIGNIFICANCE STATEMENT Altruism is a fundamental building block of our society. Emerging evidence indicates a major role of acute stress and stress-related neuromodulators in social behavior and decision-making. How and through which mechanisms stress may impact altruism remains elusive. We observed that the stress hormone cortisol was linked to diminished altruistic behavior. This effect was mediated by reduced value representations in the right dorsolateral prefrontal cortex and critically depended on the individual capacity to infer mental states of others. Our findings provide novel insights into the modulation of human altruism linked to stress-hormone dynamics and into the involved sociocognitive and neural mechanisms, with important implications for future developments of more targeted interventions for stress-related decrements in social behavior and social cognition.

A Domain-General Developmental "Do-GooD" Network Model of Prosocial Cognition in Adolescence: A Systematic Review

Adolescence is a period of substantial neural and social development, and prosocial decisions are beneficial to personal well-being, the well-being of others, and the functioning of society. Advances in network neuroscience call for a systematic synthesis and reappraisal of prosocial neural correlates during adolescent development. In this systematic review, we aim to outline the progress made in this field, identify the similarities between study results, and propose a model for prosocial cognition in adolescents to young adults. A total of 25 articles were included in this review. After reviewing and synthesizing the literature, we propose a DOmain-General Developmental "Do-GooD" network model of prosocial cognition that aligns with the reviewed literature, accounts for development, and combines elements of the value-based decision-making model with distinct value contributions from the default mode network, salience network, and control network. We offer predictions to test the "Do-GooD" model and propose new future directions for studying prosocial behavior and its development during adolescence, which in turn may lead to improving education and the development of better health interventions for adolescents.

How resource sharing resists scarcity: the role of cognitive empathy and its neurobiological mechanisms

Resource scarcity challenges individuals' willingness to share limited resources with other people. Still, lots of field studies and laboratory experiments have shown that sharing behaviors do not disappear under scarcity. Rather, some individuals are willing to share their scarce resources with others in a similar way as when the resource is abundant, which is crucial for the maintenance and development of human society. Here, we designed a novel paradigm in which subjects decided whether (and how much) to share an amount of "relieving resources" for counteracting unpleasant noises, which mimics real-life situations that people cost their own resources to help others escape from adversity. Overall, the robustness of resource sharing under scarcity was positively correlated with individual level of the cognitive component of empathy across two independent experiments. Resource insufficiency modulated the activations of several brain regions (including the TPJ, mPFC, and PCC) as well as the functional connection (from the rTPJ to the mPFC) within the mentalizing brain network, but the modulatory effect decreased as a function of cognitive empathy. We also applied the administration of oxytocin and found significant effects on sharing behavior among individuals with a higher level of cognitive empathy, but not their low-level counterparts. These findings highlight the importance of empathy to resource sharing under scarcity and explain the underlying neurobiological mechanisms.

The neural signatures of social hierarchy-related learning and interaction: A coordinate- and connectivity-based meta-analysis

Numerous neuroimaging studies have investigated the neural mechanisms of two mutually independent yet closely related cognitive processes aiding humans to navigate complex societies: social hierarchy-related learning (SH-RL) and social hierarchy-related interaction (SH-RI). To integrate these heterogeneous results into a more fine-grained and reliable characterization of the neural basis of social hierarchy, we combined coordinate-based meta-analyses with connectivity and functional decoding analyses to understand the underlying neuropsychological mechanism of SH-RL and SH-RI. We identified the anterior insula and temporoparietal junction (dominance detection), medial prefrontal cortex (information updating and computation), and intraparietal sulcus region, amygdala, and hippocampus (social hierarchy representation) as consistent activated brain regions for SH-RL, but the striatum, amygdala, and hippocampus associated with reward processing for SH-RI. Our results provide an overview of the neural architecture of the neuropsychological processes underlying how we understand, and interact within, social hierarchy.

Birth order and prosociality in the early adolescent brain

Birth order is a crucial environmental factor for child development. For example, later-born children are relatively unlikely to feel secure due to sibling competition or diluted parental resources. The positive effect of being earlier-born on cognitive intelligence is well-established. However, whether birth order is linked to social behavior remains controversial, and the neural correlates of birth order effects in adolescence when social cognition develops remain unknown. Here, we explored the birth order effect on prosociality using a large-scale population-based adolescent cohort. Next, since the amygdala is a key region for sociality and environmental stress, we examined amygdala substrates of the association between birth order and prosociality using a subset neuroimaging cohort. We found enhanced prosociality in later-born adolescents (N = 3160), and observed the mediating role of larger amygdala volume (N = 208) and amygdala-prefrontal functional connectivity with sex-selective effects (N = 183). We found that birth order, a non-genetic environmental factor, affects adolescent social development via different neural substrates. Our findings may indicate the later-born people’s adaptive survival strategy in stressful environments.

Neural mechanisms of deliberate dishonesty: Dissociating deliberation from other control processes during dishonest behaviors

Numerous studies have sought proof of whether people are genuinely honest by testing whether cognitive control mechanisms are recruited during honest and dishonest behaviors. The underlying assumption is: Deliberate behaviors require cognitive control to inhibit intuitive responses. However, cognitive control during honest and dishonest behaviors can be required for other reasons than deliberation. Across 58 neuroimaging studies (1,211 subjects), we investigated different forms of honest and dishonest behaviors and demonstrated that many brain regions previously implicated in dishonesty may reflect more general cognitive mechanisms. We argue that the motivational/volitional dimension is central to deliberation and provide evidence that motivated dishonest behaviors recruit the perigenual anterior cingulate cortex. This work questions the view that cognitive control is a hallmark of dishonesty.

Structural brain differences in recovering and weight-recovered adult outpatient women with anorexia nervosa

BACKGROUND

Anorexia nervosa is a complex psychiatric illness that includes severe low body weight with cognitive distortions and altered eating behaviors. Brain structures, including cortical thicknesses in many regions, are reduced in underweight patients who are acutely ill with anorexia nervosa. However, few studies have examined adult outpatients in the process of recovering from anorexia nervosa. Evaluating neurobiological problems at different physiological stages of anorexia nervosa may facilitate our understanding of the recovery process.

METHODS

Magnetic resonance imaging (MRI) images from 37 partially weight-restored women with anorexia nervosa (pwAN), 32 women with a history of anorexia nervosa maintaining weight restoration (wrAN), and 41 healthy control women were analyzed using FreeSurfer. Group differences in brain structure, including cortical thickness, areas, and volumes, were compared using a series of factorial f-tests, including age as a covariate, and correcting for multiple comparisons with the False Discovery Rate method.

RESULTS

The pwAN and wrAN cohorts differed from each other in body mass index, eating disorder symptoms, and social problem solving orientations, but not depression or self-esteem. Relative to the HC cohort, eight cortical thicknesses were thinner for the pwAN cohort; these regions were predominately right-sided and in the cingulate and frontal lobe. One of these regions, the right pars orbitalis, was also thinner for the wrAN cohort. One region, the right parahippocampal gyrus, was thicker in the pwAN cohort. One volume, the right cerebellar white matter, was reduced in the pwAN cohort. There were no differences in global white matter, gray matter, or subcortical volumes across the cohorts.

CONCLUSIONS

Many regional structural differences were observed in the pwAN cohort with minimal differences in the wrAN cohort. These data support a treatment focus on achieving and sustaining full weight restoration to mitigate possible neurobiological sequela of AN. In addition, the regions showing cortical thinning are similar to structural changes reported elsewhere for suicide attempts, anxiety disorders, and autistic spectrum disorder. Understanding how brain structure and function are related to clinical symptoms expressed during the course of recovering from AN is needed.

The modulation of social behavior and empathy via oral contraceptives and female sex hormones

Oral contraceptives (OC) and endogenous female sex hormones in naturally cycling women (NC) are related to a wide range of psychological variables (eg, cognition and affect). Little research on social behavior has been done. One study documented a tendency towards more prosocial behavior in NC than OC women, but the underlying neuroendocrine mechanisms remain unknown. The sex hormones progesterone and estradiol are potential candidates. We analyzed social decision-making and social behavior in 83 healthy women (38 OC and 45 NC) via the Social Value Orientation (SVO) and in real social interactions within a paradigm adapted from behavioral economics. We also measured empathy, and collected saliva samples to quantify the basal levels of estradiol and progesterone. Our analyses revealed higher levels of prosocial behavior and emotional empathy in NC than in OC women, a finding supported by higher levels of prosocial decisions in NC than OC women in the SVO. Regarding the underlying biological mechanisms, we detected lower progesterone levels in OC than NC women. Exploratory analyses revealed a negative correlation between progesterone and trust on the trend level. We found no correlations between estradiol and behavior. Our findings provide evidence that OC modulate social behavior and initial indications of a possible modulation by progesterone. Further research is needed to replicate our findings and extend them to other social behaviors.

Neuroscientific approaches to study prosociality

Prosociality is a core feature of human functioning and has been a topic of interest across disciplinary boundaries for decades. In this review, we highlight different neuroscientific approaches that have enriched traditional psychological methods for studying prosocial behavior among individuals and groups. First, we outline findings from task-based neuroimaging studies that provide correlational evidence for the involvement of different neural mechanisms in prosocial behavior. Next, we present different brain stimulation studies that show several brain areas to be causally related to prosocial behavior. Furthermore, we outline the task-independent neural trait approach that quantifies temporally stable brain-based characteristics in an effort to uncover sources of interindividual differences in prosocial preferences. We discuss how the findings from these approaches have contributed to our understanding of prosocial behavior and suggest directions for future research.

Neurocomputational models of altruistic decision-making and social motives: Advances, pitfalls, and future directions

This article discusses insights from computational models and social neuroscience into motivations, precursors, and mechanisms of altruistic decision-making and other-regard. We introduce theoretical and methodological tools for researchers who wish to adopt a multilevel, computational approach to study behaviors that promote others' welfare. Using examples from recent studies, we outline multiple mental and neural processes relevant to altruism. To this end, we integrate evidence from neuroimaging, psychology, economics, and formalized mathematical models. We introduce basic mechanisms-pertinent to a broad range of value-based decisions-and social emotions and cognitions commonly recruited when our decisions involve other people. Regarding the latter, we discuss how decomposing distinct facets of social processes can advance altruistic models and the development of novel, targeted interventions. We propose that an accelerated synthesis of computational approaches and social neuroscience represents a critical step towards a more comprehensive understanding of altruistic decision-making. We discuss the utility of this approach to study lifespan differences in social preference in late adulthood, a crucial future direction in aging global populations. Finally, we review potential pitfalls and recommendations for researchers interested in applying a computational approach to their research. This article is categorized under: Economics > Interactive Decision-Making Psychology > Emotion and Motivation Neuroscience > Cognition Economics > Individual Decision-Making.

Age-related differences in negative cognitive empathy but similarities in positive affective empathy

Empathy, among other social-cognitive processes, changes across adulthood. More specifically, cognitive components of empathy (understanding another's perspective) appear to decline with age, while findings for affective empathy (sharing another's emotional state) are rather mixed. Structural and functional correlates underlying cognitive and affective empathy in aging and the extent to which valence affects empathic response in brain and behavior are not well understood yet. To fill these research gaps, younger and older adults completed a modified version of the Multifaceted Empathy Test, which measures both cognitive and affective empathy as well as empathic responding to both positive and negative stimuli (i.e., positive vs. negative empathy). Adopting a multimodal imaging approach and applying multivariate analysis, the study found that for cognitive empathy to negative emotions, regions of the salience network including the anterior insula and anterior cingulate were more involved in older than younger adults. For affective empathy to positive emotions, in contrast, younger and older adults recruited a similar brain network including main nodes of the default mode network. Additionally, increased structural microstructure (fractional anisotropy values) of the posterior cingulum bundle (right henisphere) was related to activation of default mode regions during affective empathy for positive emotions in both age groups. These findings provide novel insights into the functional networks subserving cognitive and affective empathy in younger and older adults and highlight the importance of considering valence in empathic response in aging research. Further this study, for the first time, underscores the role of the posterior cingulum bundle in higher-order social-cognitive processes such as empathy, specifically for positive emotions, in aging.

A Feature-Based Network Analysis and fMRI Meta-Analysis Reveal Three Distinct Types of Prosocial Decisions

Tasks that measure correlates of prosocial decision-making share one common feature: agents can make choices that increase the welfare of a beneficiary. However, prosocial decisions vary widely as a function of other task features. The diverse ways that prosociality is defined and the heterogeneity of prosocial decisions have created challenges for interpreting findings across studies and identifying their neural correlates. To overcome these challenges, we aimed to organize the prosocial decision-making task space of neuroimaging studies. We conducted a systematic search for studies in which participants made decisions to increase the welfare of others during functional magnetic resonance imaging. We identified shared and distinct features of these tasks and employed an unsupervised graph-based approach to assess how various forms of prosocial decision-making are related in terms of their low-level components (e.g. task features like potential cost to the agent or potential for reciprocity). Analyses uncovered three clusters of prosocial decisions, which we labeled as cooperation, equity and altruism. This feature-based representation of the task structure was supported by results of a neuroimaging meta-analysis that each type of prosocial decisions recruited diverging neural systems. Results clarify some of the existing heterogeneity in how prosociality is conceptualized and generate insight for future research and task paradigm development.

Reflectivity relates differently to pro sociality in naïve and strategic subjects

Is pro sociality a natural impulse or the result of a self-controlled behavior? We investigate this issue in a lab in the field experiment with participants from the general adult population in Italy. We find two key results: first, that there is a positive relationship between pro sociality and strategic reasoning. Second, that reflectivity relates to lower pro sociality but only among strategic subjects, indicating that the intuitive view of pro sociality is valid only among strategic individuals. Non-strategic individuals are instead intuitively selfish. We surmise that these results emerge due to a common cognitive root between strategizing and pro sociality, namely empathy.

The tDCS effect on Prosocial Behavior: A Meta-Analytic Review

Previous studies have shown that transcranial direct current stimulation (tDCS) could potentially promote prosocial behaviors. However, results from randomized controlled trials are inconsistent. The current meta-analysis aimed to assess the effects of anodal and cathodal tDCS using single-session protocols on prosocial behaviors in healthy young adults and explore potential moderators of these effects. The results showed that compared with sham stimulation, anodal (excitatory) stimulation significantly increased (g = 0.27, 95% CI [0.11, 0.43], Z = 3.30, P = 0.001) and cathodal (inhibitory) stimulation significantly decreased prosocial behaviors (g = −0.19, 95% CI [−0.39, −0.01], Z = −1.95, P = 0.051) using a multilevel meta-analytic model. These effects were not significantly modulated by stimulation parameters (e.g. duration, intensity and site) and types of prosocial behavior. The risk of publication bias for the included effects was minimal, and no selective reporting (e.g. P-hacking) was found in the P-curve analysis. This meta-analysis showed that both anodal and cathodal tDCS have small but significant effects on prosocial behaviors. The current study provides evidence that prosocial behaviors are linked to the activity of the ‘social brain’. Future studies are encouraged to further explore whether tDCS could effectively treat social dysfunctions in psychiatry disorders.

Testosterone reduces generosity through cortical and subcortical mechanisms

Recent evidence has linked testosterone, a major sex hormone, to selfishness in economic decision-making. Here, we aimed to investigate the neural mechanisms through which testosterone reduces generosity by combining functional MRI with pharmacological manipulation among healthy young males in a double-blind, placebo-controlled, between-subject design. After testosterone or placebo gel administration, participants performed a social discounting task in which they chose between selfish options (benefiting only the participant) and generous options (providing also some benefit to another person at a particular social distance). At the behavioral level, testosterone reduced generosity compared to the placebo. At the neural level (n = 60), the temporoparietal junction (TPJ) encoded the other-regarding value of the generous option during generous choices, and this effect was attenuated by testosterone, suggesting that testosterone reduced the consideration of other's welfare as underpinned by TPJ activity. Moreover, TPJ activity more strongly reflected individual differences in generosity in the placebo than the testosterone group. Furthermore, testosterone weakened the relation between the other-regarding value of generous decisions and connectivity between the TPJ and a region extending from the insula into the striatum. Together, these findings suggest that a network encompassing both cortical and subcortical components underpins the effects of testosterone on social preferences.

Differences in Diffusion-Weighted Imaging and Resting-State Functional Connectivity Between Two Culturally Distinct Populations of Prairie Vole

BACKGROUND

We used the highly prosocial prairie vole to test the hypothesis that higher-order brain structure-microarchitecture and functional connectivity (FC)-would differ between males from populations with distinctly different levels of prosocial behavior. Specifically, we studied males from Illinois (IL), which display high levels of prosocial behavior, and first generation males from Kansas dams and IL males (KI), which display the lowest level of prosocial behavior and higher aggression. Behavioral differences between these males are associated with overexpression of estrogen receptor alpha in the medial amygdala and bed nucleus of the stria terminalis and neuropeptide expression in the paraventricular nucleus.

METHODS

We compared apparent diffusion coefficient, fractional anisotropy, and blood oxygen level-dependent resting-state FC between males.

RESULTS

IL males displayed higher apparent diffusion coefficient in regions associated with prosocial behavior, including the bed nucleus of the stria terminalis, paraventricular nucleus, and anterior thalamic nuclei, while KI males showed higher apparent diffusion coefficient in the brainstem. KI males showed significantly higher fractional anisotropy than IL males in 26 brain regions, with the majority being in the brainstem reticular activating system. IL males showed more blood oxygen level-dependent resting-state FC between the bed nucleus of the stria terminalis, paraventricular nucleus, and medial amygdala along with other brain regions, including the hippocampus and areas associated with social and reward networks.

CONCLUSIONS

Our results suggest that gray matter microarchitecture and FC may play a role the expression of prosocial behavior and that differences in other brain regions, especially the brainstem, could be involved. The differences between males suggests that this system represents a potentially valuable model system for studying emotional differences and vulnerability to stress and addiction.