Morality and empathy are both crucial in building human society. Yet the relationship between them has been merely explored. The present study revealed how the morality influenced empathy for pain by comparing the ERPs elicited by pictures showing the targets’ in pain primed by different moral information about the targets. We found that when the target was a moral one or a neutral one, the painful pictures elicited significantly larger amplitude in N2 than the non-painful pictures, but when the target was an immoral one, the difference between the amplitudes of N2 component elicited by painful and non-painful pictures became insignificant. We proposed that this effect was induced by the decreased affective arousal when observing an immoral person in pain. The reduced neural response towards the immoral one’s pain can keep us alert when we face the potentially dangerous people thereby increasing our chance of survival. SLORTEA results showed the source of this difference in N2 localized in the ventral medial prefrontal cortex (vmPFC) and the rostral anterior cingulate cortex (rACC) areas.

As an important cognitive bias, the framing effect shows that our decision preferences are sensitive to the verbal description (i.e., frame) of options. This study focuses on the neural underpinnings of the social framing effect, which is based on decision-making regarding other people. A novel paradigm was used in which participants made a trade-off between economic benefits and the feelings of others. This decision was described as either a “harm” to, or “not helping,” other persons in two conditions (Harm frame vs Help frame). Both human males and females were recruited. Participants behaved more prosocially for Harm frame compared with Help frame, resulting in a significant social framing effect. Using functional magnetic resonance imaging, Experiment 1 showed that the social framing effect was associated with stronger activation in the temporoparietal junction (TPJ), especially its right part. The functional connectivity between the right TPJ (rTPJ) and medial prefrontal cortex predicted the social framing effect on the group level. In Experiment 2, we used transcranial direct current stimulation to modulate the activity of the rTPJ and found that the social framing effect became more prominent under anodal (excitatory) stimulation, while the nonsocial framing effect elicited by the economic gain/loss gambling frame remained unaffected. The rTPJ results might be associated with moral conflicts modulated by the social consequences of an action or different levels of mentalizing with others under different frame conditions, but alternative interpretations are also worth noting. These findings could help elucidate the psychological mechanisms of the social framing effect.SIGNIFICANCE STATEMENTPrevious studies have suggested that the framing effect is generated from an interaction between the amygdala and anterior cingulate cortex. This opinion, however, is based on findings from nonsocial framing tasks. Recent research has highlighted the importance of distinguishing between the social and nonsocial framing effects. The current study focuses on the social framing effect and finds out that the temporoparietal junction and its functional connectivity with the medial prefrontal cortex play a significant role. Additionally, modulating the activity of this region leads to changes in social (but not nonsocial) framing effect. Broadly speaking, these findings help understand the difference in neural mechanisms between social and nonsocial decision-making. Meanwhile, they might be illuminating to promote helping behavior in society.

Previous behavioral studies have shown that sharing painful experiences can strengthen social bonds and promote mutual prosociality, yet the neural mechanisms underlying this phenomenon remain unclear. We hypothesized that sharing a painful experience induces brain-to-brain synchronization and mutual empathy for each other's pain between pain-takers and pain-observers, which then leads to enhanced social bonding. To test this hypothesis, we adopted an electroencephalographic (EEG) hyper-scanning technique to assess neuronal and behavioral activity during a Pain-Sharing task in which high- or low-intensity pain stimulation was randomly delivered to one participant of a dyad on different experimental trials. Single-brain analysis showed that sensorimotor α-oscillation power was suppressed more when expecting high-intensity pain than when expecting low-intensity pain similarly for self-directed or partner-directed pain. Dual-brain analysis revealed that expecting high-intensity pain induced greater brain-to-brain synchronization of sensorimotor α-oscillation phases between pain-takers and pain-observers than did expecting low-intensity pain. Mediation analysis further revealed that brain-to-brain synchronization of sensorimotor α-oscillations mediated the effects of pain-stimulation intensity on mutual affective sharing for partner-directed pain. This mutual affective empathy during the task predicted the social bonding, as indexed by prosocial inclinations measured after the task. These results support the hypothesis that sharing a painful experience triggers emotional resonance between pairs of individuals through brain-to-brain synchronization of neuronal α-oscillations recorded over the sensorimotor cortex, and this emotional resonance further strengthens social bonds and motivates prosocial behavior within pairs of individuals.

People tell lies not only for their own self-interests but sometimes also to help others. Little is known about the ways in which different types of goals modulate behaviors and neural responses in deception. The present study investigated the neural processes associated with spontaneous deception that occurs with altruistic reasons (i.e. the money would be donated to charity), self-serving reasons (i.e. the participant receives all of the money) and mixed goals (i.e. the money would be equally split between the participant and the charity). Altruistic motivation for deception reduced the intensity of moral conflict and the subsequent mental cost of resolving this conflict, reflected by a smaller N2–P3 effect in the purely altruistic condition. When making decisions about whether to lie, self-interest was a stronger motivator than others’ interests, and the participants tended to lie more for themselves than for others. When the lie could be mutually beneficial for both of the self and others, the participants tended to lie even when they knew that they could be easily caught, but they actually lied for their own self-interest rather than for altruistic reasons. These findings shed light on the neural basis of ‘good lies’ and decision-making in mutually beneficial situations.

Internet addiction disorder (IAD) is associated with deficits in social communication and avoidance of social contacts. It has been hypothesized that people with IAD may have an impaired capacity for empathy. The purpose of the current study was to examine the processing of empathy for others’ pain in subjects with and without IAD. Event-related potentials (ERPs) produced in response to the pictures showing others in painful and non-painful situations were recorded in 16 IAD subjects and 16 healthy controls (HCs). The N1, N2, P3, and the late positive potential (LPP) components of recorded ERPs were compared between the two groups. Robust picture × group interactions were observed for N2 and P3. The painful pictures elicited larger N2 and P3 amplitudes than did non-painful pictures in the HC group but not in the IAD group. These results suggest that in both of the early automatic and the later cognitive process of other’s pain, the IADs show lower discrimination ability than the HCs. This study provides the psychophysical evidence of empathy deficits in association with IAD. Further studies combining multidimensional measurements of empathy are needed to confirm this finding.