When the body fosters empathy: The interconnectivity between bodily reactivity, meditation, and embodied abstract concepts.

Empathy is a fundamental social ability that allows humans to infer others' emotions and intentions. Empathy is thought to be rooted in bodily sensations coming from the autonomic nervous system. In parallel, the functionality and perceptions coming from the autonomic nervous system could be improved by practicing activities that involve mind-body interactions, such as meditation. Furthermore, perceptions from the autonomic nervous system are thought to be important in the embodiment of abstract concepts. Consequently, in the current study, we collected data online from 581 participants and explored the associations between levels of empathy and (1) the practice of meditation, music, and sports; (2) the impact of self-report measures on bodily awareness and reactivity; and (3) the embodiment of abstract concepts in interoception. In line with previous studies, Meditators were found to have higher empathy scores than Non-Meditators. In addition, lower levels of autonomic reactivity in organs above the diaphragm were associated with higher empathy. Finally, we also observed that empathy was positively associated with interoceptive components of abstract concepts in those participants with high autonomic reactivity. Taken together, the results suggest that meditation practice and having low autonomic reactivity are associated with empathy, arguably through the downregulation of autonomic responses. Implications for mind-body interaction in meditation and its role in promoting empathy are discussed.

Callousness, exploitativeness, and tracking of cooperation incentives in the human default network.

Human cognitive capacities that enable flexible cooperation may have evolved in parallel with the expansion of frontoparietal cortical networks, particularly the default network. Conversely, human antisocial behavior and trait antagonism are broadly associated with reduced activity, impaired connectivity, and altered structure of the default network. Yet, behaviors like interpersonal manipulation and exploitation may require intact or even superior social cognition. Using a reinforcement learning model of decision-making on a modified trust game, we examined how individuals adjusted their cooperation rate based on a counterpart's cooperation and social reputation. We observed that learning signals in the default network updated the predicted utility of cooperation or defection and scaled with reciprocal cooperation. These signals were weaker in callous (vs. compassionate) individuals but stronger in those who were more exploitative (vs. honest and humble). Further, they accounted for associations between exploitativeness, callousness, and reciprocal cooperation. Separately, behavioral sensitivity to prior reputation was reduced in callous but not exploitative individuals and selectively scaled with responses of the medial temporal subsystem of the default network. Overall, callousness was characterized by blunted behavioral and default network sensitivity to cooperation incentives. Exploitativeness predicted heightened sensitivity to others' cooperation but not social reputation. We speculate that both compassion and exploitativeness may reflect cognitive adaptations to social living, enabled by expansion of the default network in anthropogenesis.

Sex and Age Differences in Ontogeny of Alloparenting: A Relation to Forebrain DRD1, DRD2, and HTR2A mRNA Expression?

Alloparenting refers to the practice of caring for the young by individuals other than their biological parents. The relationship between the dynamic changes in psychological functions underlying alloparenting and the development of specific neuroreceptors remains unclear. Using a classic 10-day pup sensitization procedure, together with a pup preference and pup retrieval test on the EPM (elevated plus maze), we showed that both male and female adolescent rats (24 days old) had significantly shorter latency than adult rats (65 days old) to be alloparental, and their motivation levels for pups and objects were also significantly higher. In contrast, adult rats retrieved more pups than adolescent rats even though they appeared to be more anxious on the EPM. Analysis of mRNA expression using real-time-PCR revealed a higher dopamine D2 receptor (DRD2) receptor expression in adult hippocampus, amygdala, and ventral striatum, along with higher dopamine D1 receptor (DRD1) receptor expression in ventral striatum compared to adolescent rats. Adult rats also showed significantly higher levels of 5-hydroxytryptamine receptor 2A (HTR2A) receptor expression in the medial prefrontal cortex, amygdala, ventral striatum, and hypothalamus. These results suggest that the faster onset of alloparenting in adolescent rats compared to adult rats, along with the psychological functions involved, may be mediated by varying levels of dopamine DRD1, DRD2, and HTR2A in different forebrain regions.

Protocol of the study for predicting empathy during VR sessions using sensor data and machine learning.

Virtual reality (VR) technology is often referred to as the 'ultimate empathy machine' due to its capability to immerse users in alternate perspectives and environments beyond their immediate physical reality. In this study, participants will be immersed in 3-dimensional 360° VR videos where actors express different emotions (sadness, happiness, anger, and anxiousness). The primary objective is to investigate the potential relationship between participants' empathy levels and the changes in their physiological attributes. The empathy levels will be self-reported with questionnaires, and physiological attributes will be measured using different sensors. The main outcome of the study will be a machine learning model to predict a person's empathy level based on their physiological responses while watching VR videos. Despite the existence of established methodologies and metrics in research and clinical domains, our aim is to contribute to addressing the gap of a universally accepted "gold standard" for assessing empathy. Additionally, we expect to deepen our understanding of the relationship between different emotions and psychological attributes, gender differences in empathy, and the impact of narrative context on empathic responses.

Long-term music instruction is partially associated with the development of socioemotional skills.

This study aims to investigate the development of pitch-matching, rhythmic entrainment, and socioemotional skills in children who received formal music instruction and other non-music based after school programs. Eighty-three children, averaging 6.81 years old at baseline, were enrolled in either a music, sports, or no after-school program and followed over four years. The music program involved formal and systematic instruction in music theory, instrumental technique, and performance. Most control participants had no music education; however, in some instances, participants received minimal music education at school or at church. Musical development was measured using a pitch-matching and drumming-based rhythmic entrainment task. Sharing behavior was measured using a variation of the dictator game, and empathy was assessed using three different assessments: the Index of Empathy for Children and Adolescence (trait empathy), the Reading the Mind in the Eyes Test (theory of mind), and a Fiction Emotion-Matching task (state empathy). Results revealed no time-related associations in pitch-matching ability; however, formal music instruction improved pitch-matching relative to controls. On the contrary, improvements in rhythmic entrainment were best explained by age-related changes rather than music instruction. This study also found limited support for a positive association between formal music instruction and socioemotional skills. That is, individuals with formal music instruction exhibited improved emotion-matching relative to those with sports training. In terms of general socioemotional development, children's trait-level affective empathy did not improve over time, while sharing, theory of mind, and state empathy did. Additionally, pitch-matching and rhythmic entrainment did not reliably predict any socioemotional measures, with associations being trivial to small. While formal music instruction benefitted pitch-matching ability and emotion-matching to an audiovisual stimulus, it was not a significant predictor of rhythmic entrainment or broader socioemotional development. These findings suggest that the transfer of music training may be most evident in near or similar domains.

Emotional awareness for self and others and empathic abilities in clinical depression during acute illness and recovery.

BACKGROUND: The present longitudinal investigation had two major goals. First, we intended to clarify whether depressed patients are characterized by impairments of emotional awareness for the self and the other during acute illness and whether these impairments diminish in the course of an inpatient psychiatric treatment program. Previous research based on the performance measure Levels of Emotional Awareness Scale (LEAS) provided inconsistent findings concerning emotional self-awareness in clinical depression. Second, we investigated whether cognitive and affective empathic abilities change from acute illness to recovery in depressed patients. METHODS: Fifty-eight depressed patients were tested on admission and after 6-8 weeks of inpatient psychiatric treatment. A sample of fifty-three healthy individuals were also examined twice at an interval of 6-8 weeks. The LEAS and the Interpersonal Reactivity Index (IRI) were administered to assess emotional awareness and empathic abilities. Written texts were digitalized and then analyzed using the electronic scoring program geLEAS, the German electronic Levels of Emotional Awareness Scale. RESULTS: Depressed patients reported more depressive symptoms than healthy controls and less severe depressive symptomatology at time 2 compared to time 1. Independent of time, depressed individuals tended to show lower geLEAS self scores and had lower geLEAS other scores than healthy individuals. Depressed patients showed higher personal distress scores than healthy individuals at both measurement times. No group differences were observed for the cognitive empathy scales of the IRI (perspective taking and fantasy) and empathic concern, but empathic concern decreased significantly in depressed patients from time 1 to time 2. Empathic abilities as assessed by the IRI were not significantly correlated with emotional awareness for others, neither in the whole sample, nor in the patient and control subsample. CONCLUSIONS: Depressed patients seem to be characterized by impairments in emotional awareness of others during acute illness and recovery, but they also tend to show deficits in emotional self-awareness compared to healthy individuals. Self-reported cognitive empathic abilities seem to be at normal levels in depressed patients, but their heightened self-focused affective empathy may represent a vulnerability factor for depressive disorders.

Psychopathy, pain, and pain empathy: A psychophysiological study.

The present study examined whether people higher in psychopathy experienced less self-reported and psychophysiological nociceptive pressure than people lower in psychopathy. We also examined whether psychopathy affects empathy for others' pain via self-reported and psychophysiological measures. Three hundred and sixty-nine students (18-78 years; M = 26, SD = 9.34) were screened for psychopathic traits using the Youth Psychopathy Inventory (YPI). Stratified sampling was used to recruit 49 adults residing in the highest (n = 23) and lowest (n = 26) 20% of the psychopathy spectrum. Using skin conductance response (SCR) and self-report responses, participants responded to individually adjusted intensities of pneumatic pressure and others' pain images and completed self-reported psychopathy and empathy measures (Triarchic Psychopathy Measure, TriPm; Interpersonal Reactivity Index, IRI). People higher in psychopathy self-reported feeling less nociceptive pressure compared to people lower in psychopathy, yet we did not find any differences in SCR to nociceptive pressure. However, when viewing other people in pain, the high psychopathy group displayed lower SCR and lower self-reported empathy compared to those lower in psychopathy. Our results suggest psychopathic traits relate to problems empathising with others' pain, as well as the perception of nociceptive pressure. We also show support for the theory of dual harm which has been receiving increasing attention. Consequently, psychopathy interventions should focus both on recognising and empathising with the pain of others.

Recognition of Dynamic Emotional Expressions in Children and Adults and Its Associations with Empathy.

This present study investigates emotion recognition in children and adults and its association with EQ and motor empathy. Overall, 58 children (33 5-6-year-olds, 25 7-9-year-olds) and 61 adults (24 young adults, 37 parents) participated in this study. Each participant received an EQ questionnaire and completed the dynamic emotion expression recognition task, where participants were asked to identify four basic emotions (happy, sad, fearful, and angry) from neutral to fully expressed states, and the motor empathy task, where participants' facial muscle activity was recorded. The results showed that "happy" was the easiest expression for all ages; 5- to 6-year-old children performed equally well as adults. The accuracies for "fearful," "angry," and "sad" expressions were significantly lower in children than in adults. For motor empathy, 7- to 9-year-old children exhibited the highest level of facial muscle activity, while the young adults showed the lowest engagement. Importantly, individual EQ scores positively correlated with the motor empathy index in adults but not in children. In sum, our study echoes the previous literature, showing that the identification of negative emotions is still difficult for children aged 5-9 but that this improves in late childhood. Our results also suggest that stronger facial mimicry responses are positively related to a higher level of empathy in adults.

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.

Understanding Others' Distress Through Past Experiences: The Role of Memory Engram Cells in Observational Fear.

For individuals to survive and function in society, it is essential that they recognize, interact with, and learn from other conspecifics. Observational fear (OF) is the well-conserved empathic ability of individuals to understand the other's aversive situation. While it is widely known that factors such as prior similar aversive experience and social familiarity with the demonstrator facilitate OF, the neural circuit mechanisms that explicitly regulate experience-dependent OF (Exp OF) were unclear. In this review, we examine the neural circuit mechanisms that regulate OF, with an emphasis on rodent models, and then discuss emerging evidence for the role of fear memory engram cells in the regulation of Exp OF. First, we examine the neural circuit mechanisms that underlie Naive OF, which is when an observer lacks prior experiences relevant to OF. In particular, the anterior cingulate cortex to basolateral amygdala (BLA) neural circuit is essential for Naive OF. Next, we discuss a recent study that developed a behavioral paradigm in mice to examine the neural circuit mechanisms that underlie Exp OF. This study found that fear memory engram cells in the BLA of observers, which form during a prior similar aversive experience with shock, are reactivated by ventral hippocampal neurons in response to shock delivery to the familiar demonstrator to elicit Exp OF. Finally, we discuss the implications of fear memory engram cells in Exp OF and directions of future research that are of both translational and basic interest.

Heroes and villains: opposing narrative roles engage neural synchronization in the inferior frontal gyrus.

Neuroscientific studies have highlighted the role of the default mode network (DMN) in processing narrative information. Here, we examined whether the neural synchronization of the DMN tracked the appearances of protagonists and antagonists when viewing highly engaging, socially rich audiovisual narratives. Using inter-subject correlation analysis on two independent, publicly available movie-watching fMRI datasets, we computed whole-brain neural synchronization during the appearance of the protagonists and antagonists. Results showed that the inferior frontal gyrus (IFG) had higher ISC values during the appearance of the protagonists than the antagonists. Importantly, these findings were generalized in both datasets. We discuss the results in the context of information integration and emotional empathy, which are relevant to functions of the IFG. Our study presents generalizable evidence that the IFG show distinctive synchronization patterns due to differences in narrative roles.

Culture, sex and social context influence brain-to-brain synchrony: an fNIRS hyperscanning study.

BACKGROUND: Unique interpersonal synchrony occurs during every social interaction, and is shaped by characteristics of participating individuals in these social contexts. Additionally, depending on context demands, interpersonal synchrony is also altered. The study therefore aims to investigate culture, sex, and social context effects simultaneously in a novel role-play paradigm. Additionally, the effect of personality traits on synchrony was investigated across cultures, and a further exploratory analysis on the effects of these variables on pre- and post-session empathy changes was conducted. METHODS: 83 dyads were recruited in two waves from Singapore and Italy and took part in a within-subjects session where they interacted with each other as themselves (Naturalistic Conversation) and as others (Role-Play and Role Reversal). Big Five Inventory (administered pre-session) and Interpersonal Reactivity Index (administered pre- and post-session) were used as measures of personality and empathy respectively, while synchrony was measured using hyperscanning functional near-infrared spectroscopy in the prefrontal cortex. After data-preprocessing and preliminary analyses, a mixture of multiple linear regression and exploratory forward stepwise regression models were used to address the above study aims. RESULTS: Results revealed significant main and interaction effects of culture, sex and social context on brain-to-brain synchrony, particularly in the medial left cluster of the prefrontal cortex, and a unique contribution of extraversion and openness to experience to synchrony in the Italian cohort only. Finally, culture-driven differences in empathy changes were identified, where significant increases in empathy across sessions were generally only observed within the Singaporean cohort. CONCLUSIONS: Main findings indicate lowered brain-to-brain synchrony during role-playing activities that is moderated by the dyad's sex make-up and culture, implying differential processing of social interactions that is also influenced by individuals' background factors. Findings align with current literature that role-playing is a cognitively demanding activity requiring greater levels of self-regulation and suppression of self-related cognition as opposed to interpersonal co-regulation characterized by synchrony. However, the current pattern of results would be better supported by future studies investigating multimodal synchronies and corroboration.

Testing the monitor and acceptance theory: the role of training-induced changes in monitoring- and acceptance-related capacities after attention-based, socio-emotional, or socio-cognitive mental training in reducing cortisol stress reactivity.

Mindfulness-based interventions have become a popular means to reduce stress. However, the specific mechanisms driving observed stress reduction remain understudied. The Monitor and Acceptance Theory suggests that the cultivation of monitoring and acceptance skills are necessary moderators of practice-induced stress reduction. In the context of the ReSource Project, a large healthy adult sample underwent three 3-month mental training modules targeting either attentional (Presence module), socio-affective (Affect module) or socio-cognitive skills (Perspective module). In the current study, the development of a range of inter-individual differences in mindfulness-, interoception- and compassion-related traits - which mapped to either monitoring or acceptance categories - was tracked. The relationship of these training-induced changes with cortisol stress reactivity after the three distinct 3-month training modules was explored. We found that stress sensitivity was particularly modulated by a differential adaptivity of one cultivated attentional capacity - Attention regulation - which predicted higher cortisol reactivity after mere attention training (Presence) but was associated with lower stress-induced cortisol release after additional socio-affective and socio-cognitive practice (Affect and Perspective). However, this effect did not survive multiple comparisons correction, and analyses were limited by the sample size available. We conclude that our study provides preliminary support of the Monitor and Acceptance Theory, lending weight to the advantage of primary attentional increases in order to fully harness the beneficial effects of socio-affective training, ultimately leading to stress reduction. Although training-induced increases in acceptance were not directly shown to contribute to lowering cortisol stress reactivity, the data suggest an additional benefit of socio-affective and socio-cognitive training that is not directly captured within the current analyses. Our study corroborates the importance of going beyond the training of attention monitoring to foster stress resilience, and highlights that mental training relies on the co-development of several interacting processes to successfully attenuate stress. Further exploring the overarching concept of acceptance in future research may prove beneficial to the theoretical framework of MAT, and in understanding the processes by which stress reduction occurs.

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.

Exploring the transformative potential of out-of-body experiences: A pathway to enhanced empathy.

Out-of-body experiences (OBEs) are subjective phenomena during which individuals feel disembodied or perceive themselves as outside of their physical bodies, often resulting in profound and transformative effects. In particular, experiencers report greater heightened pro-social behavior, including more peaceful relationships, tolerance, and empathy. Drawing parallels with the phenomenon of ego dissolution induced by certain psychedelic substances, we explore the notion that OBEs may engender these changes through ego dissolution, which fosters a deep-seated sense of unity and interconnectedness with others. We then assess potential brain mechanisms underlying the link between OBEs and empathy, considering the involvement of the temporoparietal junction and the Default Mode Network. This manuscript offers an examination of the potential pathways through which OBEs catalyze empathic enhancement, shedding light on the intricate interplay between altered states of consciousness and human empathy.

Dissecting shared pain representations to understand their behavioral and clinical relevance.

Accounts of shared representations posit that the experience of pain and pain empathy rely on similar neural mechanisms. Experimental research employing novel analytical and methodological approaches has made significant advances in both the identification and targeted manipulation of such shared experiences and their neural underpinnings. This revealed that painful experiences can be shared on different representational levels, from pain-specific to domain-general features, such as negative affect and its regulation. In view of direct links between such representations and social behaviors such as prosocial behavior, conditions characterized by aberrant pain processing may come along with heavy impairments in the social domain, depending on the affected representational level. This has wide potential implications in light of the high prevalence of pain-related clinical conditions, their management, and the overuse of pain medication. In this review and opinion paper, we aim to chart the path toward a better understanding of the link between shared affect and prosocial behavior.

Individual and contextual-level predictors of progression in the bystander intervention model.

The situational model of bystander behavior is a validated 5-step process for understanding intervention in bullying and sexual harassment, yet the individual-level and contextual-level factors that facilitate the progression from one step to the next are not well understood. The purpose of the current study was to examine whether individual characteristics (social-emotional skills, affective empathy, cognitive empathy, and personal attitudes toward bullying and sexual harassment) and contextual-level factors (school climate and perceived peer attitudes toward bullying and sexual harassment) explained the association between subsequent steps of the bystander intervention model. A sample of 788 high school students completed several validated measures of these constructs. Structural equation modeling analysis revealed that each step significantly and positively predicted the next step, and the addition of a direct path from accepting responsibility to helping improved model fit. The mediational model indicated that individual-level characteristics had significant direct effects on interpreting bullying and sexual harassment as problems, accepting responsibility, and helping, and indirect effects from noticing the bullying and sexual harassment to all subsequent steps except knowing. In contrast, contextual-level effects contributed to accepting responsibility in an inverse direction.

Beyond physical sensations: investigating empathy and prosocial behavior in vicarious pain responders.

Empathy, the capacity to share others' emotional experiences, has been proposed as a key motivation for altruistic behavior in both humans and animals. Sharing another's emotional experience may generate a self-embodied simulation of their emotional state, fostering understanding and promoting prosocial behavior. Vicarious pain responders report sensing physical pain when observing others in pain. Whether this ability extends to emotional experiences remains unexplored. Using both questionnaires and ecologically valid behavioral tasks, we explored whether vicarious pain responders differ from nonresponders in empathic abilities and prosocial behavior. Participants watched video clips of people describing a negative emotional life event. We operationalized several empathic abilities and responses (empathic accuracy, affective synchrony, emotional reaction, and empathic motivation) based on participants' and targets' responses during and after watching the videos. Participants were also engaged in a donation task measuring tendency for prosocial behavior. Findings reveal that compared to nonresponders, vicarious pain responders exhibit enhanced empathic accuracy, intensified emotional reactions to others' emotional pain, and a greater motivation to communicate with the target. This study marks the first behavioral evidence showcasing vicarious pain responders' empathic abilities, reactions, and motivation in response to nonphysical pain of others, expanding our knowledge of this phenomenon and its association with broader empathic abilities.

Self-Compassion, Stressor Exposure, and Negative Affect: A Daily Diary Study of Older Adults.

OBJECTIVES: Self-compassion has been identified as a psychological resource for aging well. To date, self-compassion among older adults has typically been conceptualized as a trait variable. This study examined whether day-to-day (state) variability in self-compassion was associated with negative affective reactivity to daily stressors. METHODS: Daily diary assessment methods were used to examine the potential moderating role of between- and within-person self-compassion on the relationship between daily stressors and negative affect. A community-based sample of 107 older adults aged 65+ completed questionnaires once daily over 14 days. RESULTS: Multilevel modeling revealed that 37% of the variance in self-compassion occurred within persons. Daily self-compassion moderated the relationship between daily stressor exposure and daily negative affect. On days with greater stressor exposure than usual, older adults showed less negative affective reactivity on days when self-compassion was higher, compared with days when self-compassion was lower. No moderating effects were observed for between-person (trait) self-compassion. DISCUSSION: These findings suggest that self-compassion in older adults should be conceptualized as both state and trait variables and that state self-compassion may be protective in the stress-reactivity pathway. Future research should investigate whether brief self-compassion interventions might help older adults to avoid or downregulate negative emotions in response to stressors.

Intracranial EEG signals disentangle multi-areal neural dynamics of vicarious pain perception.

Empathy enables understanding and sharing of others' feelings. Human neuroimaging studies have identified critical brain regions supporting empathy for pain, including the anterior insula (AI), anterior cingulate (ACC), amygdala, and inferior frontal gyrus (IFG). However, to date, the precise spatio-temporal profiles of empathic neural responses and inter-regional communications remain elusive. Here, using intracranial electroencephalography, we investigated electrophysiological signatures of vicarious pain perception. Others' pain perception induced early increases in high-gamma activity in IFG, beta power increases in ACC, but decreased beta power in AI and amygdala. Vicarious pain perception also altered the beta-band-coordinated coupling between ACC, AI, and amygdala, as well as increased modulation of IFG high-gamma amplitudes by beta phases of amygdala/AI/ACC. We identified a necessary combination of neural features for decoding vicarious pain perception. These spatio-temporally specific regional activities and inter-regional interactions within the empathy network suggest a neurodynamic model of human pain empathy.