Subliminal perception of others' physical pain induces personal distress rather than empathic concern

Abstract

Background: What is our immediate reaction when we witness someone experiencing pain? The empathy-altruism hypothesis predicts that observers would display empathy and a tendency to approach the person in pain. Alternatively, the threat value of pain hypothesis (TVPH) argues that others' pain serves as a signal of threat and should induce observers' avoidance response.

Methods: To examine these two hypotheses, three experiments were conducted. The experiments aimed to investigate the impact of subliminal exposure to others' physical pain on participants' emotional and behavioural responses.

Results: The results revealed that subliminal pain priming resulted in faster response and attentional bias to fearful faces compared to sad faces (Experiment 1), faster reaction times in recognizing fear-related words compared to anger-related words during a lexical decision task (Experiment 2), and faster avoidance responses towards anger-related words, as opposed to approaching responses towards positive words (Experiment 3).

Conclusions: The consistent findings across all experiments revealed that subliminal perception of pain scenes elicited fear emotion and immediate avoidance responses. Therefore, the outcomes of our study provide supportive evidence for the TVPH.

Keywords: Emotional and behavioural response; Empathy-altruism hypothesis; Pain perception; Subliminal priming; Threat value of pain hypothesis.

Fig. 1

Example of a no pain and a pain scene

Fig. 2

Example masked images of a no pain and a pain scene

Fig. 3

Example of emotional faces from a female model (From left to right: sadness, fear, neutral)

Fig. 4

Illustration of the procedure in Experiment 1

Fig. 5

Mean RT of each condition. Error bars represent standard errors

Fig. 6

Mean attentional bias indices of each condition. Error bars represent standard errors

Fig. 7

Illustration of the procedure in Experiment 2

Fig. 8

Mean RT of each condition. Error bars represent standard errors

Fig. 9

Mean accuracy of each condition. Error bars represent standard errors

Fig. 10

Illustration of the procedure in Experiment 3

Fig. 11

Mean RT of each condition. Error bars represent standard errors

Fig. 12

Mean accuracy of each condition. Error bars represent standard errors