Acute stress during witnessing injustice shifts third-party interventions from punishing the perpetrator to helping the victim.

People tend to intervene in others' injustices by either punishing the transgressor or helping the victim. Injustice events often occur under stressful circumstances. However, how acute stress affects a third party's intervention in injustice events remains open. Here, we show a stress-induced shift in third parties' willingness to engage in help instead of punishment by acting on emotional salience and central-executive and theory-of-mind networks. Acute stress decreased the third party's willingness to punish the violator and the severity of the punishment and increased their willingness to help the victim. Computational modeling revealed a shift in preference of justice recovery from punishment the offender toward help the victim under stress. This finding is consistent with the increased dorsolateral prefrontal engagement observed with higher amygdala activity and greater connectivity with the ventromedial prefrontal cortex in the stress group. A brain connectivity theory-of-mind network predicted stress-induced justice recovery in punishment. Our findings suggest a neurocomputational mechanism of how acute stress reshapes third parties' decisions by reallocating neural resources in emotional, executive, and mentalizing networks to inhibit punishment bias and decrease punishment severity.

Exercise intervention in middle-aged and elderly individuals with insomnia improves sleep and restores connectivity in the motor network.

Exercise is a potential treatment to improve sleep quality in middle-aged and elderly individuals. Understanding exercise-induced changes in functional plasticity of brain circuits that underlie improvements in sleep among middle-aged and older adults can inform treatment of sleep problems. The aim of the study is to identify the effects of a 12-week exercise program on sleep quality and brain functional connectivity in middle-aged and older adults with insomnia. The trial was registered with Chinese Clinical Trial Register (ChiCTR2000033652). We recruited 84 healthy sleepers and 85 individuals with insomnia. Participants with insomnia were assigned to receive either a 12-week exercise intervention or were placed in a 12-week waitlist control condition. Thirty-seven middle-aged and older adults in the exercise group and 30 in the waitlist group completed both baseline and week 12 assessments. We found that middle-aged and older adults with insomnia showed significantly worse sleep quality than healthy sleepers. At the brain circuit level, insomnia patients showed decreased connectivity in the widespread motor network. After exercise intervention, self-reported sleep was increased in the exercise group (P < 0.001) compared to that in the waitlist group. We also found increased functional connectivity of the motor network with the cerebellum in the exercise group (P < 0.001). Moreover, we observed significant correlations between improvement in subjective sleep indices and connectivity changes within the motor network. We highlight exercise-induced improvement in sleep quality and functional plasticity of the aging brain.

Same allocation proposed by an individual or a group elicits distinct responses: Evidence from event-related potentials and neural oscillation.

People tend to perceive the same information differently depending on whether it is expressed in an individual or a group frame. It has also been found that the individual (vs. group) frame of expression tends to lead to more charitable giving and greater tolerance of wealth inequality. However, little is known about whether the same resource allocation in social interactions elicits distinct responses depending on proposer type. Using the second-party punishment task, this study examined whether the same allocation from different proposers (individual vs. group) leads to differences in recipient behavior and the neural mechanisms. Behavioral results showed that reaction times were longer in the unfair (vs. fair) condition, and this difference was more pronounced when the proposer was the individual (vs. group). Neural results showed that proposer type (individual vs. group) influenced early automatic processing (indicated by AN1, P2, and central alpha band), middle processing (indicated by MFN and right frontal theta band), and late elaborative processing (indicated by P3 and parietal alpha band) of fairness in resource allocation. These results revealed more attentional resources were captured by the group proposer in the early stage of fairness processing, and more cognitive resources were consumed by processing group-proposed unfair allocations in the late stage, possibly because group proposers are less identifiable than individual proposers. The findings provide behavioral and neural evidence for the effects of "individual/group" framing leading to cognitive differences. They also deliver insights into social governance issues, such as punishing individual and/or group violations.

The impact of social distance on the processing of social evaluation: evidence from brain potentials and neural oscillations.

Previous research indicates that social distance can influence people's social evaluations of others. Individuals tend to evaluate intimate others more positively than distant others. The present study investigates the modulating effect of social distance on the time course underlying individuals' evaluation processes of others using adequate electroencephalography methods. The results reveal that in the initial processing stage, the P2 component is larger when friends are negatively evaluated, whereas this pattern is the opposite for strangers. In the second stage, medial frontal negativity and early mid-frontal theta band activity is enhanced for negative evaluations of friends, whereas this effect is absent in social evaluations of strangers. At the late stage, the P3 is larger for positive evaluations of friends but insensitive to social evaluations of strangers, and the late mid-frontal theta is also modulated by social distance. These findings provide direct and powerful evidence that social distance modulates individuals' evaluations of others with different levels of intimacy throughout all processing stages.

Fear of negative evaluation modulates the processing of social evaluative feedback with different valence and contexts.

Fear of negative evaluation (FNE) is a susceptible and maintaining factor of social anxiety disorders. However, the question, how people process negative evaluation is influenced by individual differences in FNE, is poorly understood. To clarify the habitual processing characteristics of individuals with different levels of FNE, electroencephalography was recorded when two groups of participants with high FNE (hFNE) and low FNE (lFNE) performed a social evaluation perception task in which the feedback context/source (human vs. a computer) and valence (thumb-up/like vs. thumb-down/dislike) were manipulated. We found effects of feedback source and valence on N1, P2, and P3, which reflect early attention, integrated perception, and elaborative processing, respectively, as well as general reward effects on reward positivity (RewP) across contexts. Importantly, compared to the lFNE group, the hFNE group showed larger midfrontal N1 and theta oscillation in response to negative feedback indicating dislike (vs. like), and also showed larger P3. These findings suggest that individuals with hFNE are more attentional vigilance to negative (vs. positive) social feedback, implying that individuals with different levels of FNE assign different implicit threat values to social-evaluation threat stimuli.

Effectiveness of Mindful Self-Compassion Training Supported by Online Peer Groups in China: A Pilot Study.

Context: Self-compassion training involves the cultivation of feelings of warmth and safety, presence, and interconnectedness. Mindful Self-Compassion (MSC) training in a group setting has been found to increase self-compassion, mindfulness, and emotional well-being. Objective: The current study intended to examine the outcomes of live, online, videoconference-based MSC training with online peer-support for nonclinical populations in different cities in China. Design: The research team designed a pre-post pilot study. Setting: The study took place at Renmin University in Beijing, China. Participants: Participants were 253 Chinese individuals who were recruited from different regions in China through online advertisements. Intervention: Participants took part in online MSC training in a two-hour, group class each week for eight weeks and received support from online peer groups and through a half-day in-person retreat. Outcome Measures: Self-report outcomes were obtained at baseline and postintervention, using the Self Compassion Scale (SCS) and the Compassion for Others Scale (CS) for primary outcomes, and the Depression, Anxiety, and Stress Scale (DASS-21), the Fear of Compassion Scale (FOCS), the Satisfaction with Life Scale (SWLS), the Subjective Happiness Scale (SHS), and the Cognitive and Affective Mindfulness Scale (CAMS-R), for secondary outcomes. A fixed effects model was used to test for within-group changes in the scales. Results: The online MSC program yielded a high retention rate. Of the 206 first-time participants, 179 (86.9%) attended six or more of the eight MSC sessions, and 183 (88.8%) completed the assessments at both baseline and postintervention. Of the 183 retained participants, 97.8% were female, with an average age of 37.8 ± 7.9; 94% had college or higher education. For all scales, the within-person changes occurred in the expected direction; positive attributes and experiences increased, while negative attributes and experiences decreased. Conclusions: The study showed that first-time participants in China in an online MSC training that was supported by online peer groups had high attendance rates, high assessment completion, and favorable results. These preliminary outcomes suggest that future studies with more rigorous designs are warranted to further investigate online training with peer support as an effective and efficient approach to disseminate MSC training in China.

Effects of Transcranial Direct Current Stimulation Over the Left Primary Motor Cortex on Verbal Intelligence.

Previous studies have shown that changes in gray matter density and volume in the left primary motor cortex are significantly associated with changes in individuals' verbal intelligence quotient (VIQ), but not with their performance intelligence quotient (PIQ). In the present study, we examined the effects of transcranial direct current stimulation (tDCS) over the left primary motor cortex on performance in intelligence tests. We chose four subtests (two each for VIQ and PIQ) of the Wechsler Adult Intelligence Scale-Chinese Revised version and randomized participants into anodal, cathodal, and sham groups. We found that anodal stimulation significantly improved performance in verbal intelligence subtests compared to cathodal and sham stimulation, while performance intelligence subtest scores did not change in any stimulation condition. These findings suggest that the excitation level of the left primary motor cortex has a unique effect on verbal intelligence.

Mortality salience enhances neural activities related to guilt and shame when recalling the past.

Mortality salience (MS) influences cognition and behavior. However, its effect on emotion (especially moral emotions) and the underlying neural correlates are unclear. We investigated how MS priming modulated guilt and shame in a later recall task using functional magnetic resonance imaging. The behavioral results indicated that MS increased self-reported guilt but not shame. The neural results showed that MS strengthened neural activities related to the psychological processes of guilt and shame. Specifically, for both guilt and shame, MS increased activation in a region associated with self-referential processing (ventral medial prefrontal cortex). For guilt but not shame, MS increased the activation of regions associated with cognitive control (orbitofrontal cortex) and emotion processing (amygdala). For shame but not guilt, MS decreased brain functional connectivity related to self-referential processing. A direct comparison showed that MS more strongly decreased a functional connectivity related to self-referential processing in the shame than in the guilt condition. Additionally, the activation of insula during MS priming was partly predictive of neural activities related to guilt and shame in the subsequent recall task. Our study sheds light on the psychological and neural mechanisms of MS effects on moral emotions and provides theoretical insights for enriching terror management theory.

Effects of transcranial direct current stimulation over the right dorsolateral prefrontal cortex on fairness-related decision-making.

Neuroimaging studies suggest that the right dorsolateral prefrontal cortex (rDLPFC) is an important brain area involved in fairness-related decision-making. In the present study, we used transcranial direct current stimulation (tDCS) over the rDLPFC to investigate the effects of changed cortical excitability on fairness norm enforcement in social decision-making. Participants received anodal, cathodal or sham stimulation before performing a modified ultimatum game task, in which participants were asked to accept or reject the proposer's offer and self-rate the intensity of their anger at offers on a 7-point scale. The results showed that the rejection rate of unfair offers and anger level were higher in the anodal compared to the sham and cathodal groups and that the level of anger at unfair offers can predict the rejection rate. Furthermore, the fairness effect of RTs was more prominent in the anodal group than in the sham and cathodal groups. Our findings validate the causal role of the rDLPFC in fairness-related decision-making through tDCS, suggesting that strengthening the rDLPFC increases individuals' reciprocal fairness in social decision-making, both in subjective rating and behaviors.

Timing of iron deficiency and recognition memory in infancy.

Objective: To determine the relationship between iron deficiency (or iron-deficient, ID) and neural correlates of recognition memory depending on ID timing (gestation vs. infancy) and infant age at testing (9 vs. 18 months).Study design: Event-related potentials (ERP) were used in a visual recognition memory task (mother vs. stranger face) to compare healthy term infants according to iron status at birth and 9 months. Fetal-neonatal ID was defined as cord serum ferritin < 75 µg/l or zinc protoporphrin/heme ratio > 118 µmol/mol, postnatal ID as ≥ 2 abnormal iron measures at 9 months with normal cord-blood iron status, and iron-sufficient as not ID at birth or 9 months. Recognition of mother faces was measured by negative component (Nc) and late slow wave (LSW). These ERP components reflect attention and memory updating processes, respectively.Results: All groups showed differences in Nc amplitude elicited by mother and stranger faces at 9 months. At 18 months, only postnatal ID and iron-sufficient groups showed condition differences in Nc amplitude. However, the 2 groups were different in the involved brain regions. For LSW, only the 2 ID groups showed condition differences in amplitude at 9 months. At 18 months, condition differences were not observed in any group.Conclusions: This study indicates that the timing of ID in early life (fetal-neonatal vs. postnatal) modulates the impact of ID on recognition memory. Such impact also varies depending on the age of infants at testing (9 vs. 18 months).

From gratitude to injustice: Neurocomputational mechanisms of gratitude-induced injustice.

Gratitude shapes individuals' behaviours and impacts the harmony of society. Many previous studies focused on its association with prosocial behaviours. A possibility that gratitude can lead to moral violation has been overlooked until recently. Nevertheless, the neurocognitive mechanisms of gratitude-induced moral violation are still unclear. On the other hand, though neural correlates of the gratitude's formation have been examined, the neural underpinnings of gratitude-induced behaviour remain unknown. For addressing these two overlapped research gaps, we developed novel tasks to investigate how participants who had received voluntary (Gratitude group) or involuntary help (Control group) punished their benefactors' unfairness with functional magnetic resonance imaging (fMRI). The Gratitude group punished their benefactors less than the Control group. The self-report and computational modelling results demonstrated a crucial role of the boosted protection tendency on behalf of benefactors in the gratitude-induced injustice. The fMRI results showed that activities in the regions associated with mentalizing (temporoparietal junction) and reward processing (ventral medial prefrontal cortex) differed between the groups and were related to the gratitude-induced injustice. They suggest that grateful individuals concern for benefactors' benefits, value chances to interact with benefactors, and refrain from action that perturbs relationship-building (i.e., exert less punishment on benefactors' unfairness), which reveal a dark side of gratitude and enrich the gratitude theory (i.e., the find-bind-remind theory). Our findings provide psychological, computational, and neural accounts of the gratitude-induced behaviour and further the understanding of the nature of gratitude.

Social value orientation modulates fairness processing during social decision-making: evidence from behavior and brain potentials.

Social value orientation (SVO) characterizes stable individual differences by an inherent sense of fairness in outcome allocations. Using the event-related potential (ERP), this study investigated differences in fairness decision-making behavior and neural bases between individuals with prosocial and proself orientations using the Ultimatum Game (UG). Behavioral results indicated that prosocials were more prone to rejecting unfair offers with stronger negative emotional reactions compared with proselfs. ERP results revealed that prosocials showed a larger P2 when receiving fair offers than unfair ones in a very early processing stage, whereas such effect was absent in proselfs. In later processing stages, although both groups were sensitive to fairness as reflected by an enhanced medial frontal negativity (MFN) for unfair offers and a larger P3 for fair offers, prosocials exhibited a stronger fairness effect on these ERP components relative to proselfs. Furthermore, the fairness effect on the MFN mediated the SVO effect on rejecting unfair offers. Findings regarding emotional experiences, behavioral patterns and ERPs provide compelling evidence that SVO modulates fairness processing in social decision-making, whereas differences in neural responses to unfair vs fair offers as evidenced by the MFN appear to play important roles in the SVO effect on behavioral responses to unfairness.

Social distance modulates outcome processing when comparing abilities with others.

Social comparison occurs when individuals evaluate themselves in comparison with others. Social distance can influence the effect of social comparison. Using event-related potentials, this study examined how social distance affects the time course of outcome processing when individuals compare themselves with others in terms of ability. Participants were asked to perform a dot estimation task with a friend and a stranger. The results showed the effect of social distance on the N1, feedback-related negativity (FRN), and P300, such that the N1 and P300 were greater for the outcome when pairing with the stranger than when pairing with the friend, whereas the FRN was more negative for the outcome when pairing with the friend than when pairing with the stranger, suggesting that participants allocated more attention resources to the stranger's outcome during the early, automatic (the N1) and later, controlled processing stage (the P300). In addition, the FRN was sensitive to the valence of both self- and other-outcomes, and the FRN valence effect of self-outcome was modulated by friends' outcomes but not by strangers' outcomes, indicating that at the semi-automatic processing stage, closer social distance increases the likelihood of individuals being affected by the comparison targets. These results suggest that when comparing with others in the ability dimension, social distance plays a different role in different stages of outcome processing. At the primary stage of outcome processing, individuals are more likely to compare with close others in the ability dimension.

Spectral clustering-based resting-state network detection approach for functional near-infrared spectroscopy.

In recent years, studying the resting-state network (RSN) by using functional near-infrared spectroscopy (fNIRS) has received increased attention. The previous resting-state fNIRS studies mainly adopted the seed-based correlation and the independent component analysis to detect RSN. However, these methods have several inherent problems. For example, the seed-based correlation method relies on seed region selection and neglects the interactions among multiple regions. The ICA method usually relies on manual component selection, which requires rich experience from the experimenter. In the present study, we developed a new approach for fNIRS-RSN detection based on spectral clustering. It consists of two steps. First, it calculates the individual-level partition of the fNIRS measurement region by using spectral clustering with an automatically determined cluster number. Second, the individual-level partitioning results are further clustered. Those clusters with high group consistency are determined as RSN clusters. We validated the method by using simulated data and in vivo fNIRS data. The results showed that the proposed method was effective and robust for fNIRS-RSN detection.

Your losses are mine: The influence of empathic concern on evaluative processing of others' outcomes.

Neural responses to others' decision-making outcomes can be modulated by many social factors. Using the event-related potential (ERP) technique, we explored the neural mechanisms of empathic concern modulating evaluative processing of others' outcomes. Participants were asked to perform a gambling task for three beneficiaries: themselves and two strangers. One stranger was an economically underprivileged student requiring help (high-empathy condition); the other stranger was a student with no upsetting information to induce empathic concern (low-empathy condition). ERP results showed that the valence effect of the feedback-related negativity (FRN) was larger when participants exhibited high empathic concern than when they did not. The FRN responses to strangers' outcomes in the high-empathy condition were as strong as those to their own outcomes. The P300 showed no differences between the low- and high-empathy conditions. These findings indicate that empathic concern could modulate the early stage of outcome processing, implying empathic emotional/altruistic motivational impacts of others' outcomes.

Increasing the Difference in Decision Making for Oneself and for Others by Stimulating the Right Temporoparietal Junction.

The right temporoparietal junction (rTPJ) has been thought to be associated with the difference in self-other decision making. In the present study, using noninvasive transcranial direct current stimulation (tDCS), we examined whether stimulating the rTPJ could modulate the self-other decision-making difference. We found that after receiving anodal stimulation of the rTPJ, participants were more likely to choose a high-value item for others than for themselves in the situations where the win probability of the high-value item was equal to or greater than that of a low-value item, indicating that elevating the cortical excitability of the rTPJ might increase the self-other decision-making difference in certain decision contexts. Our results suggest that decision making for others depends on neural activity in the rTPJ and regulation of the excitability of the rTPJ can influence the self-other decision-making difference.

Early distinction between shame and guilt processing in an interpersonal context.

Shame and guilt have been compared in many behavioral and functional magnetic resonance imaging studies. However, the time course of shame and guilt processing remains unknown. We conducted an event-related potential (ERP) study to investigate the temporal dynamics of shame and guilt in an interpersonal context. Behaviorally, participants reported "shame" when their wrong advice was correctly rejected by a confederate, whereas reported "guilt" when their wrong advice resulted in economic loss of a confederate. The ERP results showed significant difference between the shame and guilt conditions in the early P2 component (140-220 ms) over the frontal region and the alpha oscillations (240-1000 ms) over the parietal region. No significant difference was found between the shame and guilt conditions in the N2, P3, and theta oscillations. These results supported previous findings that shame compared to guilt involves more self-referential processing, whereas guilt compared to shame involves more empathetic processing, and provided evidence that the distinction between shame and guilt could occur in an early stage.

The effect of shame on anger at others: awareness of the emotion-causing events matters.

Numerous studies have found that shame increases individuals' anger at others. However, according to recent theories about the social function of shame and anger at others, it is possible that shame controls individuals' anger at others in specific conditions. We replicated previous findings that shame increased individuals' anger at others' unfairness, when others were not aware of the individual's experience of shameful events. We also found for the first time that shame controlled or even decreased individuals' anger at others' unfairness, when others were aware of the individual's experience of shameful events. The results were consistent when shame was induced by either a recall paradigm or an imagination paradigm, and in either the ultimatum game or the dictator game. This suggests that shame strategically controls individuals' anger at others to demonstrate that they are willing to benefit others, when facing the risk of social exclusion. Our findings highlight the interpersonal function of shame and deepen the understanding of the relationship between shame and anger at others.

Differentiating guilt and shame in an interpersonal context with univariate activation and multivariate pattern analyses.

Guilt and shame are usually evoked during interpersonal interactions. However, no study has compared guilt and shame processing under such circumstances. In the present study, we investigated guilt and shame in an interpersonal context using functional magnetic resonance imaging (fMRI). Behaviorally, participants reported more "guilt" when their wrong advice caused a confederate's economic loss, whereas they reported more "shame" when their wrong advice were correctly refused by the confederate. The fMRI results showed that both guilt and shame activated regions related to the integration of theory of mind and self-referential information (dorsal medial prefrontal cortex, dmPFC) and to the emotional processing (anterior insula). Guilt relative to shame activated regions linked with theory of mind (supramarginal gyrus and temporo-parietal junction) and cognitive control (orbitofrontal cortex/ventrolateral prefrontal cortex and dorsolateral prefrontal cortex). Shame relative to guilt revealed no significant results. Using multivariate pattern analysis, we demonstrated that in addition to the regions found in the univariate activation analysis, the ventral anterior cingulate cortex and dmPFC could also distinguish guilt and shame. These results do not only echo previous studies of guilt and shame using recall and imagination paradigms but also provide new insights into the psychological and neural mechanisms of guilt and shame.

The impact of trust decision-making on outcome processing: Evidence from brain potentials and neural oscillations.

It may be beneficial, although risky, to decide to trust others during social interactions in daily life. The current study explored the time course of the effect of trust decisions on outcome evaluation processing using electroencephalographic (EEG) techniques. Twenty-two healthy young adults made trust or distrust decisions regarding a message they received from a stranger in a card game. The results showed that at the early stage of outcome processing, feedback-related negativity (FRN) was more negative for losses than for gains, and more importantly, this valence effect of FRN was greater for outcomes following trust decisions than distrust decisions. At the later stage, the P3 was larger for gains than for losses and for outcomes following trust decisions than distrust decisions. In addition, at both the early and late stages, differences in the mid-frontal theta power between losses and gains were also greater in the trust condition than in the distrust condition. These findings indicate that trust decisions could effectively modulate the processing of outcome evaluation at different stages. The trust effect at the early stage of outcome processing suggests that compared to distrust decisions, trust decisions result in greater motivation and expectancy to obtain positive outcomes. While the trust effect on the later stage of outcome processing suggests that individuals pay more attention and feel stronger emotional experience to the outcomes following trust decisions. This study sheds light on the neural mechanisms of trust decisions modulating outcome processing.