Facial expressions are deeply tied to empathy, which plays an important role during social communication. The eye region is effective at conveying facial expressions, especially fear and sadness emotions. Further, it was proved that subliminal stimuli could impact human behavior. This research aimed to explore the effect of subliminal sad, fearful and neutral emotions conveyed by the eye region on a viewer’s empathy for pain using event-related potentials (ERP). The experiment used an emotional priming paradigm of 3 (prime: subliminal neutral, sad, fear eye region information) × 2 (target: painful, nonpainful pictures) within-subject design. Participants were told to judge whether the targets were in pain or not. Results showed that the subliminal sad eye stimulus elicited a larger P2 amplitude than the subliminal fearful eye stimulus when assessing pain. For P3 and late positive component (LPC), the amplitude elicited by the painful pictures was larger than the amplitude elicited by the nonpainful pictures. The behavioral results demonstrated that people reacted to targets depicting pain more slowly after the sad emotion priming. Moreover, the subjective ratings of Personal Distress (PD) (one of the dimensions in Chinese version of Interpersonal Reactivity Index scale) predicted the pain effect in empathic neural responses in the N1 and N2 time window. The current study showed that subliminal eye emotion affected the viewer’s empathy for pain. Compared with the subliminal fearful eye stimulus, the subliminal sad eye stimulus had a greater impact on empathy for pain. The perceptual level of pain was deeper in the late controlled processing stage.

Emotional contagion refers to the transmission and interaction of emotions among people. Researchers have mainly focused on its process and mechanism, often simplifying its social background due to its complexity. Therefore, in this study, we attempt to explore whether the presence and clarity of social context affect emotional contagion and the related neural mechanisms. In Experiment 1, participants were asked to report their subjective experiences after being exposed to the facial expressions of emotional expressers, with or without the corresponding social context being presented. The results revealed that positive or negative expressions from the expressers elicited corresponding emotional experiences in the receivers, regardless of the presence of social context. However, when the social context was absent, the degree of emotional contagion was greater. In Experiment 2, we further investigated the effect of the clarity of social contexts on emotional contagion and its neural mechanisms. The results showed an effect consistent with those in Experiment 1 and highlighted the special role of N1, N2, P3, and LPP components in this process. According to the emotions as social information theory, individuals may rely more on social appraisal when they lack sufficient contextual information. By referencing the expressions of others and maintaining emotional convergence with them, individuals can adapt more appropriately to their current environment.

Storytelling is an important part of human’s daily life. It is a powerful means to share emotions with others. Thus, individuals’ autobiographical memory is a suitable carrier of intentional emotional contagion. Few researchers have explored intentional emotional contagion using individuals’ autobiographical memory, especially people’s neural responses to individuals’ autobiographical memory, and the corresponding mental mechanism of emotional contagion has not been sufficiently clarified. This study investigated the intentional emotional contagion in people’s daily conversation using a functional near-infrared spectroscopy technique comprising two phases. The first phase involved speakers’ video production. In the second phase, the videos were presented to the listeners, during which we obtained listeners’ brain activities while they viewed the videos. The behavioral results showed that compared with the outcome from neutral stories, the degree of emotional contagion induced by happy stories and the degree of overlap between the speaker and the listener were larger. The brain results demonstrated that neutral stories induced greater activation than happy stories in channel 11 and channel 15. These results suggest that to be a happy girl is quite easy and sharing happiness promotes closeness. Future research directions are also provided.