Task modulations of racial bias in neural responses to others' suffering

Neural Tracking of Race-Related Information During Face Perception

Previous studies have identified two group-level processes, neural representations of interracial between-group difference and intraracial within-group similarity, that contribute to the racial categorization of faces. What remains unclear is how the brain tracks race-related information that varies across different faces as an individual-level neural process involved in race perception. In three studies, we recorded functional MRI signals when Chinese adults performed different tasks on morphed faces in which proportions of pixels contributing to perceived racial identity (Asian vs White) and expression (pain vs neutral) varied independently. We found that, during a pain expression judgment task, tracking other-race and same-race-related information in perceived faces recruited the ventral occipitotemporal cortices and medial prefrontal/anterior temporal cortices, respectively. However, neural tracking of race-related information tended to be weakened during explicit race judgments on perceived faces. During a donation task, the medial prefrontal activity also tracked race-related information that distinguished between two perceived faces for altruistic decision-making and encoded the Euclidean distance between the two faces that predicted decision-making speeds. Our findings revealed task-dependent neural mechanisms underlying the tracking of race-related information during face perception and altruistic decision-making.

The oxytocinergic system and racial ingroup bias in empathic neural activity

Studies have indicated that the human brain exhibits a more robust neural empathic response towards individuals of the same racial ingroup than those of the outgroup. However, the impact of the oxytocinergic system on the dynamic connectivity between brain regions involved in racial ingroup bias in empathy (RIBE) and its implications for real-life social interaction intention remains unclear. To address this gap, we employed functional magnetic resonance imaging (fMRI) to investigate RIBE-modulated neural activities and the influence of the oxytocinergic system at both neural and behavioral levels. Participants homozygous for the A/A and G/G genotypes of the oxytocin receptor gene (OXTR) rs53576 polymorphism underwent scanning while making judgments about painful versus non-painful stimuli in same-race versus other-race scenarios following either oxytocin (OT) or placebo treatment. The results revealed greater activity in the anterior cingulate cortex (ACC) and anterior insula (AI) in response to same-race compared to other-race models in the G/G group but not in the A/A group. RIBE also modulated the connections between bilateral AI and the ACC, and the effect of OT on this modulatory effect was moderated by genotype rs53576 and interpersonal trust. Moreover, more extensive changes in AI-ACC connections were associated with higher levels of revenge intention in the low interpersonal trust group. Overall, our findings suggest a pivotal role of the oxytocinergic system in the RIBE-modulated neural activities and revenge intention in human interactions with the modulatory effect of interpersonal trust. This article is part of the Special Issue on "Empathic Pain".

Group empathy for pain is stronger than individual empathy for pain in the auditory modality

Humans live in collective groups and are highly sensitive to perceived emotions of a group, including the pain of a group. However, previous research on empathy for pain mainly focused on the suffering of a single individual ("individual empathy for pain"), with limited understanding of empathy for pain to a group ("group empathy for pain"). Thus, the present study aimed to investigate the cognitive neural mechanisms of group empathy for pain in the auditory modality. The study produced group painful voices to simulate the painful voices made by a group, and recruited 34 participants to explore differences between their responses to group painful voices and individual painful voices using the event-related potential (ERP) techniques. The results revealed that group painful voices were rated with higher pain intensity, more negative affective valence, and larger P2 amplitudes than individual painful voices. Furthermore, trait affective empathy scores of the participants were positively correlated with their P2 amplitudes of group painful voices. The results suggested that the group empathy for pain may facilitate affective empathetic processing in auditory modality.

Do we empathize humanoid robots and humans in the same way? Behavioral and multimodal brain imaging investigations

Humanoid robots have been designed to look more and more like humans to meet social demands. How do people empathize humanoid robots who look the same as but are essentially different from humans? We addressed this issue by examining subjective feelings, electrophysiological activities, and functional magnetic resonance imaging signals during perception of pain and neutral expressions of faces that were recognized as patients or humanoid robots. We found that healthy adults reported deceased feelings of understanding and sharing of humanoid robots' compared to patients' pain. Moreover, humanoid robot (vs. patient) identities reduced long-latency electrophysiological responses and blood oxygenation level-dependent signals in the left temporoparietal junction in response to pain (vs. neutral) expressions. Furthermore, we showed evidence that humanoid robot identities inhibited a causal input from the right ventral lateral prefrontal cortex to the left temporoparietal junction, contrasting the opposite effect produced by patient identities. These results suggest a neural model of modulations of empathy by humanoid robot identity through interactions between the cognitive and affective empathy networks, which provides a neurocognitive basis for understanding human-robot interactions.

Temporal Unfolding of Racial Ingroup Bias in Neural Responses to Perceived Dynamic Pain in Others

In this study, we investigated how empathic neural responses unfold over time in different empathy networks when viewing same-race and other-race individuals in dynamic painful conditions. We recorded magnetoencephalography signals from Chinese adults when viewing video clips showing a dynamic painful (or non-painful) stimulation to Asian and White models' faces to trigger painful (or neutral) expressions. We found that perceived dynamic pain in Asian models modulated neural activities in the visual cortex at 100 ms-200 ms, in the orbitofrontal and subgenual anterior cingulate cortices at 150 ms-200 ms, in the anterior cingulate cortex around 250 ms-350 ms, and in the temporoparietal junction and middle temporal gyrus around 600 ms after video onset. Perceived dynamic pain in White models modulated activities in the visual, anterior cingulate, and primary sensory cortices after 500 ms. Our findings unraveled earlier dynamic activities in multiple neural circuits in response to same-race (vs other-race) individuals in dynamic painful situations.

EEG evidence for racial ingroup bias in collective empathy for pain

Previous research on racial ingroup bias in empathy for pain focused on neural responses to a single person's suffering. It is unclear whether empathy for simultaneously perceived multiple individuals' pain (denoted as collective empathy in this study) is also sensitive to perceived racial identities of empathy targets. We addressed this issue by recording electroencephalography from Chinese adults who responded to racial identities of 2 × 2 arrays of Asian or White faces in which 4 faces, 1 face, or no face showed painful expressions. Participants reported greater feelings of others' pain and their own unpleasantness when viewing 4 compared to 1 (or no) painful faces. Behavioral responses to racial identities of faces revealed decreased speeds of information acquisition when responding to the face arrays with 4 (vs. 1 or no) painful expressions of Asian (but not White) faces. Moreover, Asian compared to White face arrays with 4 (vs. 1 or no) painful expressions elicited a larger positive neural response at 160-190 ms (P2) at the frontal/central electrodes and enhanced alpha synchronizations at 288-1,000 ms at the central electrodes. Our findings provide evidence for racial ingroup biases in collective empathy for pain and unravel its relevant neural underpinnings.

The vocal side of empathy: neural correlates of pain perception in spoken complaints

In the extensive neuroimaging literature on empathy for pain, few studies have investigated how this phenomenon may relate to everyday social situations such as spoken interactions. The present study used functional Magnetic Resonance Imaging (fMRI) to assess how complaints, as vocal expressions of pain, are empathically processed by listeners and how these empathic responses may vary based on speakers' vocal expression and cultural identity. Twenty-four French participants listened to short utterances describing a painful event, which were either produced in a neutral-sounding or complaining voice by both in-group (French) and out-group (French Canadian) speakers. Results suggest that the perception of suffering from a complaining voice increased activity in the emotional voice areas, composed of voice-sensitive temporal regions interacting with prefrontal cortices and the amygdala. The Salience and Theory of Mind networks, associated with affective and cognitive aspects of empathy, also showed prosody-related activity and specifically correlated with behavioral evaluations of suffering by listeners. Complaints produced by in- vs out-group speakers elicited sensorimotor and default mode activity, respectively, suggesting accent-based changes in empathic perspective. These results, while reaffirming the role of key networks in tasks involving empathy, highlight the importance of vocal expression information and social categorization processes when perceiving another's suffering during social interactions.

Creative mindset reduces racial ingroup bias in empathic neural responses

Spontaneous racial categorization of other-race individuals provides a cognitive basis of racial ingroup biases in empathy and prosocial behavior. In two experiments, we investigated whether fostering a creativity mindset reduces racial ingroup biases in empathy and undermines spontaneous racial categorization of other-race faces. Before and after a creative mindset priming procedure that required the construction of novel objects using discreteness, we recorded electroencephalography signals to Asian and White faces with painful or neutral expressions from Chinese adults to assess neural activities underlying racial ingroup biases in empathy and spontaneous racial categorization of faces. We found that a frontal-central positive activity within 200 ms after face onset (P2) showed greater amplitudes to painful (vs. neutral) expressions of Asian compared with White faces and exhibited repetition suppression in response to White faces. These effects, however, were significantly reduced by creative mindset priming. Moreover, the creative mindset priming enhanced the P2 amplitudes to others' pain to a larger degree in participants who created more novel objects. The priming effects were not observed in control participants who copied objects constructed by others. Our findings suggest that creative mindsets may reduce racial ingroup biases in empathic neural responses by undermining spontaneous racial categorization of faces.

Neural representation of perceived race mediates the opposite relationship between subcomponents of self-construals and racial outgroup punishment

Outgroup aggression characterizes intergroup conflicts in human societies. Previous research on relationships between cultural traits and outgroup aggression behavior showed inconsistent results, leaving open questions regarding whether cultural traits predict individual differences in outgroup aggression and related neural underpinnings. We conducted 2 studies to address this issue by collecting self-construal scores, EEG signals in response to Asian and White faces with painful or neutral expressions, and decisions to apply electric shocks to other-race individuals in a context of interracial conflict. We found that interdependent self-construals were well explained by 2 subcomponents, including esteem for group (EG) and relational interdependence (RI), which are related to focus on group collectives and harmonious relationships, respectively. Moreover, EG was positively associated with the decisions to punish racial outgroup targets, whereas RI was negatively related to the decisions. These opposite relationships were mediated by neural representations of perceived race at 120-160 ms after face onset. Our findings highlight the multifaceted nature of interdependent self-construal and the key role of neural representations of race in mediating the relationships of different subcomponents of cultural traits with racial outgroup punishment decisions in a context of interracial conflict.

Dissociating neural sensitivity to target identity and mental state content type during inferences about other minds

Predicting and inferring what other people think and feel (mentalizing) is central to social interaction. Since the discovery of the brain's "mentalizing network", fMRI studies have probed the lines along which the activity of different regions in this network converges and dissociates. Here, we use fMRI meta-analysis to aggregate across the stimuli, paradigms, and contrasts from past studies in order to definitively test two sources of possible sensitivity among brain regions of this network with particular theoretical relevance. First, it has been proposed that mentalizing processes depend on aspects of target identity (whose mind is considered), with self-projection or simulation strategies engaging disproportionately for psychologically close targets. Second, it has been proposed that mentalizing processes depend on content type (what the inference is), with inferences about epistemic mental states (e.g. beliefs and knowledge) engaging different processes than mentalizing about other types of content (e.g. emotions or preferences). Overall, evidence supports the conclusion that different mentalizing regions are sensitive to target identity and content type, respectively, but with some points of divergence from previous claims. Results point to fruitful directions for future studies, with implications for theories of mentalizing.

Exposure to Multicultural Context Affects Neural Response to Out-Group Faces: A Functional Magnetic Resonance Imaging Study

Recent migration and globalization trends have led to the emergence of ethnically, religiously, and linguistically diverse countries. Understanding the unfolding of social dynamics in multicultural contexts becomes a matter of common interest to promote national harmony and social cohesion among groups. The current functional magnetic resonance imaging (fMRI) study aimed to (i) explore the neural signature of the in-group bias in the multicultural context; and (ii) assess the relationship between the brain activity and people's system-justifying ideologies. A sample of 43 (22 females) Chinese Singaporeans (M = 23.36; SD = 1.41) was recruited. All participants completed the Right Wing Authoritarianism Scale and Social Dominance Orientation Scale to assess their system-justifying ideologies. Subsequently, four types of visual stimuli were presented in an fMRI task: Chinese (in-group), Indian (typical out-group), Arabic (non-typical out-group), and Caucasian (non-typical out-group) faces. The right middle occipital gyrus and the right postcentral gyrus showed enhanced activity when participants were exposed to in-group (Chinese) rather than out-group (Arabic, Indian, and Caucasian) faces. Regions having a role in mentalization, empathetic resonance, and social cognition showed enhanced activity to Chinese (in-group) rather than Indian (typical out-group) faces. Similarly, regions typically involved in socioemotional and reward-related processing showed increased activation when participants were shown Chinese (in-group) rather than Arabic (non-typical out-group) faces. The neural activations in the right postcentral gyrus for in-group rather than out-group faces and in the right caudate in response to Chinese rather than Arabic faces were in a significant positive correlation with participants' Right Wing Authoritarianism scores (p < 0.05). Furthermore, the activity in the right middle occipital gyrus for Chinese rather than out-group faces was in a significant negative correlation with participants' Social Dominance Orientation scores (p < 0.05). Results are discussed by considering the typical role played by the activated brain regions in socioemotional processes as well as the role of familiarity to out-group faces.

(Not) part of the team: Racial empathy bias in a South African minimal group study

Minimal Group Paradigm (MGP) research suggests that recategorization with an arbitrarily defined group may be sufficient to override empathy biases among salient social categories like race. However, most studies utilizing MGPs do not consider sufficiently the socio-historical contexts of social groups. Here we investigated whether the recategorization of White participants into arbitrarily defined mixed-race teams using a non-competitive MGP would ameliorate racial empathy biases towards ingroup team members in the South African context. Sixty participants rated their empathic and counter-empathic (Schadenfreude, Glückschmerz) responses to ingroup and outgroup team members in physically painful, emotionally distressing, and positive situations. As anticipated, results indicated significant ingroup team biases in empathic and counter-empathic responses. However, mixed-race minimal teams were unable to override ingroup racial empathy biases, which persisted across events. Interestingly, a manipulation highlighting purported political ideological differences between White and Black African team members did not exacerbate racial empathy bias, suggesting that such perceptions were already salient. Across conditions, an internal motivation to respond without prejudice was most strongly associated with empathy for Black African target individuals, regardless of their team status. Together, these results suggest that racial identity continues to provide a salient motivational guide in addition to more arbitrary group memberships, even at an explicit level, for empathic responding in contexts characterized by historical power asymmetry. These data further problematize the continued official use of race-based categories in such contexts.

Understanding racial bias through electroencephalography

Research on racial bias in social and cognitive psychology has focused on automatic cognitive processes such as categorisation or stereotyping. Neuroimaging has revealed differences in the neural circuit when processing social information about one's own or another's ethnicity. This review investigates the influence of racial bias on human behaviour by reviewing studies that examined changes in neural circuitry (i.e. ERP responses) during automatic and controlled processes elicited by specific tasks. This systematic analysis of specific ERP components across different studies provides a greater understanding of how social contexts are perceived and become associated with specific stereotypes and behavioural predictions. Therefore, investigating these related cognitive and neurobiological functions can further our understanding of how racial bias affects our cognition more generally and guide more effective programs and policies aimed at its mitigation.

The Experience of BIPOC Living with Chronic Pain in the USA: Biopsychosocial Factors that Underlie Racial Disparities in Pain Outcomes, Comorbidities, Inequities, and Barriers to Treatment

PURPOSE OF REVIEW

This review synthesizes recent findings related to the biopsychosocial processes that underlie racial disparities in chronic pain, while highlighting opportunities for interventions to reduce disparities in pain treatment among BIPOC.

RECENT FINDINGS

Chronic pain is a prevalent and costly public health concern that disproportionately burdens Black, Indigenous, and people of color (BIPOC). This unequal burden arises from an interplay among biological, psychological, and social factors. Social determinants of health (e.g., income, education level, and lack of access or inability to utilize healthcare services) are known to affect overall health, including chronic pain, and disproportionately affect BIPOC communities. This burden is exacerbated by exposure to psychosocial stressors (i.e., perceived injustice, discrimination, and race-based traumatic stress) and can affect biological systems that modulate pain (i.e., inflammation and pain epigenetics). Further, there are racial/ethnic disparities in pain treatment, perpetuating the cycle of undermanaged chronic pain among BIPOC.

Racial outgroup favoritism in neural responses to others' pain emerges during sociocultural interactions

Racial ingroup favoritism in empathic brain activity has been widely observed and is associated with biased behavior toward same-race and other-race individuals. We investigated whether racial outgroup favoritism in neural responses to others' pain - an objective measure of empathy - may emerge during sociocultural interactions in a new social environment. We recorded magnetoencephalography to pain and neutral expressions of Asian and White faces from White students who had stayed in China for 6-36 weeks (Experimental group) or 2-4 weeks (Control group). The experimental group showed better neural decoding of and greater insular/sensorimotor responses to pain vs. neutral expressions of Asian compared to White faces. By contrast, the control group showed better neural decoding of pain vs. neutral expressions of White than Asian faces. In addition, participants of the experimental group who had stayed longer in China showed greater sensorimotor responses to pain (vs. neutral) expressions of Asian faces but weaker sensorimotor responses to pain (vs. neutral) expressions of White faces. Our findings revealed emerging racial outgroup favoritism in brain activities associated with sensorimotor resonance and affective sharing of others' pain during sociocultural interactions.

Stronger brain activation for own baby but similar activation toward babies of own and different ethnicities in parents living in a multicultural environment

Specific facial features in infants automatically elicit attention, affection, and nurturing behaviour of adults, known as the baby schema effect. There is also an innate tendency to categorize people into in-group and out-group members based on salient features such as ethnicity. Societies are becoming increasingly multi-cultural and multi-ethnic, and there are limited investigations into the underlying neural mechanism of the baby schema effect in a multi-ethnic context. Functional magnetic resonance imaging (fMRI) was used to examine parents' (N = 27) neural responses to (a) non-own ethnic in-group and out-group infants, (b) non-own in-group and own infants, and (c) non-own out-group and own infants. Parents showed similar brain activations, regardless of ethnicity and kinship, in regions associated with attention, reward processing, empathy, memory, goal-directed action planning, and social cognition. The same regions were activated to a higher degree when viewing the parents' own infant. These findings contribute further understanding to the dynamics of baby schema effect in an increasingly interconnected social world.

The residential stability mindset increases racial in-group bias in empathy

With the deepening of internationalization, the population's mobility has greatly increased, which can impact people's intergroup relationships. The current research examined the hypothesis that residential mobility plays a crucial role in racial in-group bias in empathy (RIBE) with three studies. By manipulating the residential mobility/stability mindset and measuring subjective pain intensity ratings (Study 1) and event-related potentials (ERPs, Study 2) of Chinese adults on painful and neutral expressions of Asian and Caucasian faces, we found that the RIBE in subjective ratings and N1 amplitudes increased and P3 amplitudes decreased in the stability group. Transcranial direct current stimulation (tDCS) manipulation in Study 3 further found that anodal stimulation of the left dorsolateral prefrontal cortex (DLPFC) increased the RIBE of participants with residential stability experience but had no effect on those with residential mobility experience. As residential mobility continues to increase worldwide, we may observe concomitant changes in racial intergroup relationships.

Neural mechanisms of modulations of empathy and altruism by beliefs of others' pain

Perceived cues signaling others' pain induce empathy which in turn motivates altruistic behavior toward those who appear suffering. This perception-emotion-behavior reactivity is the core of human altruism but does not always occur in real-life situations. Here, by integrating behavioral and multimodal neuroimaging measures, we investigate neural mechanisms underlying modulations of empathy and altruistic behavior by beliefs of others' pain (BOP). We show evidence that lack of BOP reduces subjective estimation of others' painful feelings and decreases monetary donations to those who show pain expressions. Moreover, lack of BOP attenuates neural responses to their pain expressions within 200 ms after face onset and modulates neural responses to others' pain in the insular, post-central, and frontal cortices. Our findings suggest that BOP provide a cognitive basis of human empathy and altruism and unravel the intermediate neural mechanisms.

Expressive suppression to pain in others reduces negative emotion but not vicarious pain in the observer

Although there are situations where it may be appropriate to reduce one's emotional response to the pain of others, the impact of an observer's emotional expressivity on their response to pain in others is still not well understood. In the present study, we examined how the emotion regulation strategy expressive suppression influences responses to pain in others. Based on prior research findings on expressive suppression and pain empathy, we hypothesized that expressive suppression to pain expression faces would reduce neural representations of negative emotion, vicarious pain, or both. To test this, we applied two multivariate pattern analysis (MVPA)-derived neural signatures to our data, the Picture Induced Negative Emotion Signature (PINES; Chang, Gianaros, Manuck, Krishnan, and Wager (2015)) and a neural signature of facial expression induced vicarious pain (Zhou et al., 2020). In a sample of 60 healthy individuals, we found that viewing pain expression faces increased neural representations of negative emotion and vicarious pain. However, expressive suppression to pain faces reduced neural representations of negative emotion only. Providing support for a connection between neural representations of negative emotion and pain empathy, PINES responses to pain faces were associated with participants' trait-level empathy and the perceived unpleasantness of pain faces. Findings suggest that a consequence of suppressing one's facial expressions in response to the pain of others may be a reduction in the affective aspect of empathy but not the experience of vicarious pain itself.

Frontotemporal dementia, music perception and social cognition share neurobiological circuits: A meta-analysis

Frontotemporal dementia (FTD) is a neurodegenerative disease that presents with profound changes in social cognition. Music might be a sensitive probe for social cognition abilities, but underlying neurobiological substrates are unclear. We performed a meta-analysis of voxel-based morphometry studies in FTD patients and functional MRI studies for music perception and social cognition tasks in cognitively normal controls to identify robust patterns of atrophy (FTD) or activation (music perception or social cognition). Conjunction analyses were performed to identify overlapping brain regions. In total 303 articles were included: 53 for FTD (n = 1153 patients, 42.5% female; 1337 controls, 53.8% female), 28 for music perception (n = 540, 51.8% female) and 222 for social cognition in controls (n = 5664, 50.2% female). We observed considerable overlap in atrophy patterns associated with FTD, and functional activation associated with music perception and social cognition, mostly encompassing the ventral language network. We further observed overlap across all three modalities in mesolimbic, basal forebrain and striatal regions. The results of our meta-analysis suggest that music perception and social cognition share neurobiological circuits that are affected in FTD. This supports the idea that music might be a sensitive probe for social cognition abilities with implications for diagnosis and monitoring.

Oxytocin weakens self-other distinction in males during empathic responses to sadness: an event-related potentials study

By making use of event-related potential (ERP) technology, a randomized, double-blind, between-subject design study was performed in order to investigate whether OXT can weaken men’s self-other distinction during empathic responses to sad expressions. In the two experimental tasks, 39 male subjects were asked to either evaluate the emotional state shown in a facial stimulus (other-task) or to evaluate their own emotional responses (self-task). The results revealed that OXT reduced the differences in P2 (150–200 ms) amplitudes between sad and neutral expressions in the self-task but enhanced P2 to sad expressions in the other-task, indicating OXT’s role in integrating the self with others instead of separating them. In addition, OXT also reduced the LPC (400–600 ms) amplitudes between sad-neutral expressions in the self-task, implying that OXT’s weakening effects on the self-other distinction could occur at both the early and late cognitive control stages of the empathic response.

Neural dynamics of pain expression processing: Alpha-band synchronization to same-race pain but desynchronization to other-race pain

Both electroencephalography and functional magnetic resonance imaging studies have revealed enhanced neural responses to perceived pain in same-race than other-race individuals. However, it remains unclear how neural responses in the sensorimotor, cognitive, and affective subsystems vary dynamically in the first few hundreds of milliseconds to generate racial ingroup favoritism in empathy for pain. We recorded magnetoencephalography signals to pain and neutral expressions of Asian and white faces from Chinese adults during judgments of racial identity of each face. We found that pain compared to neutral expressions of same-race faces induced early increased alpha oscillations in the precuneus/parietal cortices followed by increased alpha-band oscillations in the left anterior insula and temporoparietal junction. Pain compared to neutral expressions of other-race faces, however, induced early suppression of alpha-band oscillations in the bilateral sensorimotor cortices and left insular cortex. Moreover, decreased functional connectivity between the left sensorimotor cortex and left anterior insula predicted reduced subjective feelings of other-race suffering. Our results unraveled distinct patterns of modulations of neural dynamics of sensorimotor, affective, and cognitive components of empathy by interracial relationships between an observer and a target person, which provide possible brain mechanisms for understanding racial ingroup favoritism in social behavior.

The Social Neuroscience of Prejudice

The social neuroscience approach to prejudice investigates the psychology of intergroup bias by integrating models and methods of neuroscience with the social psychology of prejudice, stereotyping, and discrimination. Here, we review major contemporary lines of inquiry, including current accounts of group-based categorization; formation and updating of prejudice and stereotypes; effects of prejudice on perception, emotion, and decision making; and the self-regulation of prejudice. In each section, we discuss key social neuroscience findings, consider interpretational challenges and connections with the behavioral literature, and highlight how they advance psychological theories of prejudice. We conclude by discussing the next-generation questions that will continue to guide the social neuroscience approach toward addressing major societal issues of prejudice and discrimination.

Interactions between oxytocin receptor gene and intergroup relationship on empathic neural responses to others' pain

Empathic neural responses to others' suffering are subject to both social and biological influences. The present study tested the hypothesis that empathic neural responses to others' pain are more flexible in an intergroup context in G/G than A/A carriers of the oxytocin receptor gene (OXTR) (rs53576). We recorded event-related brain potentials to painful vs neutral expressions of Asian and Caucasian faces that were assigned to a fellow team or an opponent team in Chinese carriers of G/G or A/A allele of OXTR. We found that G/G carriers showed greater neural responses at 136-176 ms (P2) over the frontal/central region to painful vs neutral expressions of faces with shared either racial or mini group identity. In contrast, A/A carriers showed significant empathic neural responses in the P2 time window only to the faces with both shared racial and mini group identity. Moreover, the racial in-group bias in empathic neural responses varied across individuals' empathy traits and ethnic identity for G/G but not A/A carriers. Our findings provide electrophysiological evidence for greater flexibility of empathic neural responses in intergroup contexts in G/G (vs A/A) carriers of OXTR and suggest interactions between OXTR and intergroup relationships on empathy for others' suffering.

A meta-analysis of neuroimaging studies on pain empathy: investigating the role of visual information and observers' perspective

Empathy relies on brain systems that support the interaction between an observer's mental state and cues about the others' experience. Beyond the core brain areas typically activated in pain empathy studies (insular and anterior cingulate cortices), the diversity of paradigms used may reveal secondary networks that subserve other more specific processes. A coordinate-based meta-analysis of fMRI experiments on pain empathy was conducted to obtain activation likelihood estimates along three factors and seven conditions: visual cues (body parts, facial expressions), visuospatial (first-person, thirdperson), and cognitive (self-, stimuli-, other-oriented tasks) perspectives. The core network was found across cues and perspectives, and common activation was observed in higher-order visual areas. Body-parts distinctly activated areas related with sensorimotor processing (superior and inferior parietal lobules, anterior insula) while facial expression distinctly involved the inferior frontal gyrus. Self- compared to other-perspective produced distinct activations in the left insula while stimulus- versus other-perspective produced distinctive responses in the inferior frontal and parietal lobules, precentral gyrus, and cerebellum. Pain empathy relies on a core network which is modulated by several secondary networks. The involvement of the latter seems to depend on the visual cues available and the observer's mental state that can be influenced by specific instructions.

Can empathy close the racial divide and gender gap in death penalty support?

Public opinion data indicate that the majority of US respondents support the death penalty. Research has consistently indicated, however, that Blacks and females are significantly less likely to support capital punishment than their White and male counterparts. Past research efforts attempting to account for these differences have, at best, only partially accounted for them: the racial divide and gender gap in death penalty support, while narrowed, remained evident. This study proposes that empathy, particularly ethnocultural empathy, may be a key explanatory correlate of death penalty support and that racial and gender differences in empathy may fully explain the observed racial and gender differences in death penalty support. This study uses three forms of empathy measures (cognitive, affective, and ethnocultural) to test this hypothesis using survey data from a sample of undergraduate students. Our results show that neither a variety of other "known correlates" of death penalty support nor cognitive or affective empathy scales were able to fully account for the observed racial difference in death penalty support. Ethnocultural empathy, however, was successful in reducing the effect of race on death penalty support to nonsignificance. To the best of our knowledge, this is the first study to have done so.

Neural activation in response to the two sides of emotion

Emotions are at the core of human cognition and behavior. Traditionally, emotions have been classified dichotomously as being either positive or negative. However, recent behavioral research (An et al., 2017) suggests that emotions contain both positivity and negativity. The current work investigated neural correlates of experiencing positive and negative emotions in response to happy and sad photos. Functional MRI revealed the precuneus and posterior cingulate cortex showed stronger activation when experiencing positivity compared to negativity of sadness, but not happiness, whereas the bilateral cerebellum showed greater response to positivity than negativity regardless of emotion. Results suggest that there are similarities and differences in the neural activation of positivity and negativity of happiness and sadness, consistent with previous findings (An et al., 2017). Emotion from both the neural and psychological perspectives were investigated. Further implications are discussed.

Empathy for pain motivates actions without altruistic effects: evidence of motor dynamics and brain activity

Empathy has been supposed to be a proximate mechanism of altruistic behavior. We investigated whether empathy for pain drives actions without altruistic effects and how such actions modulate neural responses to others’ pain. In two experiments, we asked healthy adults to press a button for no reason when viewing video clips showing faces with pain expressions receiving needle penetration or faces with neutral expressions receiving a cotton swab touch. Experiment 1 found that participants pressed a button with greater response force when watching painful than non-painful stimuli. Participants who reported greater unpleasant feelings pressed the button harder when viewing painful stimuli. Experiment 2 revealed that passively viewing painful vs non-painful stimuli increased blood-oxygen-level-dependent signals in the middle cingulate cortex, supplementary motor cortex, and bilateral second somatosensory and inferior frontal cortex, which, however, were reduced by the action of button press without altruistic effects. In addition, individuals who reported higher personal distress illustrated greater decrease of the second somatosensory activity induced by button press. Our results indicate that empathy for pain motivates simple actions without altruistic effects that in turn reduce neural responses to others’ pain, suggesting a functional role of action execution in self distress relief when viewing others’ suffering.

Multidimensional assessment of empathic abilities in patients with insular glioma

Recent studies have provided evidence that there are two possible systems for empathy: affective empathy (AE) and cognitive empathy (CE). Neuroimaging paradigms have proven that the insular cortex is involved in empathy processing, particularly in AE. However, these observations do not provide causal evidence for the role of the insula in empathy. Although impairments in empathy have been described following insular damage in a few case studies, it is not clear whether insular cortex is involved in CE and whether these two systems are impaired independently or laterally in patients with insular gliomas. In this study, we assessed 17 patients with an insular glioma, 17 patients with a noninsular glioma, and 30 healthy controls using a method that combined a self-report empathy questionnaire with the emotion recognition task, assessment of empathy for others' pain, and the emotional perspective-taking paradigm. We found that patients with an insular glioma had lower scores for empathic concern and perspective taking than did either healthy controls or lesion controls. The patients' abilities to recognize facial emotions, perceive others' pain, and understand the emotional perspectives of others were also significantly impaired. Furthermore, we did not observe a laterality effect on either AE or CE among those with insular lesions. These findings revealed that both AE and CE are impaired in patients with an insular glioma and that the insular cortex may be a central neuroanatomical structure in both the AE and CE systems.

Physical coldness enhances racial in-group bias in empathy: Electrophysiological evidence

Empathy for others' pain plays a key role in prosocial behavior and is influenced by intergroup relationships. Increasing evidence suggests greater empathy for racial in-group than out-group individuals' pain and the racial in-group bias undergoes sociocultural and biological influences. The present study further investigated whether and how physical environments influence racial in-group bias in empathy by testing the hypothesis that sensory experiences of physical coldness versus warmth enhance differential empathic neural responses to racial in-group vs. out-group individuals' suffering. We recorded event-related brain potentials to painful versus neutral expressions of same-race and other-race faces when participants held a cold or warm pack. We found that brain activity in the N2 (200-340ms) and P3 (400-600ms) time windows over the frontal/central region was positively shifted by painful (vs. neutral) expressions. Moreover, the N2/P3 empathic neural responses were significantly larger for same-race than other-race faces in the cold but not in the warm condition. Moreover, subjective ratings of different temperatures in the cold vs. warm conditions predicted larger changes of racial in-group bias in empathic neural responses in the N2 time window. Our findings suggest that sensory experiences of physical coldness can strengthen emotional resonance with same-race individuals.

Degraded perceptual and affective processing of racial out-groups: An electrophysiological approach

Human beings process perceptual and affective information of racial out-groups in a degraded manner. Relative to racial in-group members, we lack perceptual individuation of racial out-group members and empathize their pain to a less degree. To date, however, the relationship between the deficiency of individuation and the impairment of empathy in responding to racial out-groups remains elusive. By recording event-related brain potentials in response to racial in-group and out-group faces portraying pain and neutral expressions, we simultaneously measured neural activity that underpinned individuation and empathy. Deficiency in individuating members of racial out-groups, manifesting as reduced reactivity of face-sensitive N170 in the occipitotemporal region of the brain, predicted attenuation of fronto-central empathic response to the suffering of racial out-groups. Further, the individuation bias mediated the influence of racial prejudice on racial in-group bias in empathic neural responses. These findings suggest an interplay between degraded perceptual and affective processing of racial out-groups.

Embodied neural responses to others' suffering

To investigate whether and how facial mimicry in observers affects their empathic neural responses to others' pain expressions, we recorded event-related potentials (ERPs) from Chinese adults while viewing pain and neutral expressions of Asian and Caucasian faces. Facial mimicry was manipulated by allowing participants to freely move their facial muscles (the relaxed condition) or asking them to hold a pen horizontally using both teeth and lips to prevent facial muscle movement and facial mimicry (the blocked condition). We found that the frontal N1 at 100-120 ms was enlarged by pain vs. neutral expressions. The N1 modulation by facial expressions was significantly reduced in the blocked compared to relaxed conditions and this effect was observed for Asian but not Caucasian faces. The findings suggest that facial mimicry plays a causal role in the early empathic neural response and the embodied empathic neural responses are constrained by the racial intergroup relationship.

Mortality salience enhances racial in-group bias in empathic neural responses to others' suffering

Behavioral research suggests that mortality salience (MS) leads to increased in-group identification and in-group favoritism in prosocial behavior. What remains unknown is whether and how MS influences brain activity that mediates emotional resonance with in-group and out-group members and is associated with in-group favoritism in helping behavior. The current work investigated MS effects on empathic neural responses to racial in-group and out-group members' suffering. Experiments 1 and 2 respectively recorded event related potentials (ERPs) and blood oxygen level dependent signals to pain/neutral expressions of Asian and Caucasian faces from Chinese adults who had been primed with MS or negative affect (NA). Experiment 1 found that an early frontal/central activity (P2) was more strongly modulated by pain vs. neutral expressions of Asian than Caucasian faces, but this effect was not affected by MS vs. NA priming. However, MS relative to NA priming enhanced racial in-group bias in long-latency neural response to pain expressions over the central/parietal regions (P3). Experiment 2 found that MS vs. NA priming increased racial in-group bias in empathic neural responses to pain expression in the anterior and mid-cingulate cortex. Our findings indicate that reminding mortality enhances brain activity that differentiates between racial in-group and out-group members' emotional states and suggest a neural basis of in-group favoritism under mortality threat.

Challenging emotional prejudice by changing self-concept: priming independent self-construal reduces racial in-group bias in neural responses to other's pain

Humans show stronger empathy for in-group compared with out-group members' suffering and help in-group members more than out-group members. Moreover, the in-group bias in empathy and parochial altruism tend to be more salient in collectivistic than individualistic cultures. This work tested the hypothesis that modifying self-construals, which differentiate between collectivistic and individualistic cultural orientations, affects in-group bias in empathy for perceived own-race vs other-race pain. By scanning adults using functional magnetic resonance imaging, we found stronger neural activities in the mid-cingulate, left insula and supplementary motor area (SMA) in response to racial in-group compared with out-group members' pain after participants had been primed with interdependent self-construals. However, the racial in-group bias in neural responses to others' pain in the left SMA, mid-cingulate cortex and insula was significantly reduced by priming independent self-construals. Our findings suggest that shifting an individual's self-construal leads to changes of his/her racial in-group bias in neural responses to others' suffering.

Beta oscillations reveal ethnicity ingroup bias in sensorimotor resonance to pain of others

People evaluate members of their own social group more favorably and empathize more strongly with their ingroup members. Using electroencephalography (EEG), we explored whether resonant responses of sensorimotor cortex to the pain of others are modulated by the ethnicity of these others. White participants watched video clips of ethnic ingroup and outgroup hands, being either penetrated by a needle syringe or touched by a cotton swab, while EEG was recorded. Time-frequency analysis was applied to Laplacian-transformed signals from the sensors overlying sensorimotor cortex in order to assess event-related desynchronization and synchronization (ERD/ERS) of sensorimotor mu (7-12 Hz) and beta (13-30 Hz) rhythms. When watching needle injections, beta ERD was significantly stronger for ingroup compared with outgroup hands. This ethnicity bias was restricted to painful actions, as beta ERD for ingroup and outgroup hands neither differed when observing no-pain videos, nor during presentation of the hands without any treatment. Such vicarious sensorimotor activation could play a role in social interaction by enhancing the understanding of the feelings and reactions of others and hence facilitating behavioral coordination among group members.

Shared beliefs enhance shared feelings: religious/irreligious identifications modulate empathic neural responses

Recent neuroimaging research has revealed stronger empathic neural responses to same-race compared to other-race individuals. Is the in-group favouritism in empathic neural responses specific to race identification or a more general effect of social identification-including those based on religious/irreligious beliefs? The present study investigated whether and how intergroup relationships based on religious/irreligious identifications modulate empathic neural responses to others' pain expressions. We recorded event-related brain potentials from Chinese Christian and atheist participants while they perceived pain or neutral expressions of Chinese faces that were marked as being Christians or atheists. We found that both Christian and atheist participants showed stronger neural activity to pain (versus neutral) expressions at 132-168 ms and 200-320 ms over the frontal region to those with the same (versus different) religious/irreligious beliefs. The in-group favouritism in empathic neural responses was also evident in a later time window (412-612 ms) over the central/parietal regions in Christian but not in atheist participants. Our results indicate that the intergroup relationship based on shared beliefs, either religious or irreligious, can lead to in-group favouritism in empathy for others' suffering.