Background & Aims

Our perception of pain in others and the subsequent empathic and prosocial responses are influenced by contextual factors and stable psychosocial (dispositional) traits of the observer [1,2]. As contextual factors fluctuate, identifying dispositional traits in the observer can advance our understanding of individual differences in pain empathy and provide valuable insights for improving our response to others’ suffering. Despite extensive research on empathy and prosocial responses to others’ pain in humans [3,4], a notable gap persists in considering non-human animals, compounded by the lack of pain-/animal-related normative metrics for such investigations [5,6]. The current study aims to design and validate the first image-based task to measure how people perceive and respond to pain in other humans and animals and to identify stable psychosocial factors of the observer that predict perceived pain and prosocial responses.

Methods

The task included 36 images of adult wounded (pain cues) and unwounded (no pain cues) humans and animals. Our perception of animals is influenced by how we categorize them [5,6]. Thus, the animal category included images of pets (i.e., cats and dogs) and food animals (i.e., pigs and cows). The task was validated in 50 USA adults recruited via Prolific, who rated each image on a 0-100 scale based on their estimate of the subject’s pain (perceived pain) and willingness to invest free time in the subject’s recovery (prosocial response). After validation, 407 psychology students (Univ. of Melbourne) completed the task and a series of validated questionnaires on their experience/beliefs around pain and interpersonal/interspecies empathy, altruism, and prejudices. We used t-tests to assess differences in perceived pain and prosocial responses to human vs. animal images, and to pet vs. food animal images. We used stepwise multiple regressions to identify predictors of these constructs.

Results

Regardless of pain cues, participants perceived animals to be more in pain than humans (T’s>2.2, p’s<.02) and were more willing to help them than humans (T’s>11.5, p’s<.001). Among animals, people perceived food animals to be more in pain and were more willing to help them compared to pets only when pain cues were not present (T’s>4, p’s<.001). When pain cues were explicit, we saw the opposite: people perceived pets as more in pain and were more willing to help them than food animals (T’s>12, p’s<.001). Previous exposure to others in pain, negative pain beliefs, and personal distress positively predicted perceived pain regardless of category (i.e., in humans, pets, and food animals) (F’s>10, p<.001; T’s>2.4, p’s<.017). These same variables, along with altruism and empathic care, predicted prosocial responses in all categories (F’s>11.8, p’s<.001; T’s>2.5, p’s<.011). Animal-related prejudices reduced prosocial behavior toward pets and food animals (F’s>17.5; p’s<.001).

Conclusions

Our findings suggest an empathetic bias towards animals (vs. humans), possibly due to perceptions of their vulnerability or challenges in recognizing their pain. Without pain cues, participants were more empathetic towards food animals, likely influenced by awareness of their typical living conditions. In contrast, explicit pain cues shifted empathy towards pets, potentially due to cognitive dissonance, limiting acknowledgment of food animals’ suffering, given individuals’ awareness of their involvement in food production.

We found a significant overlap in predictors of perception and response to pain in all species. Pain-related variables consistently influenced pain sensitivity and prosocial behavior toward all species. Thus, they may hold greater importance across human and animal contexts than previously recognized. Regarding empathy, distress was the main form of empathy contributing to perceived pain in others, whereas both distress and care contributed to prosocial behavior.

References

(1) McCrystal, K. N., Craig, K. D., Versloot, J., Fashler, S. R. & Jones, D. N. Perceiving pain in others: Validation of a dual processing model. Pain 152, 1083–1089 (2011).

(2) Coll, M.-P., Grégoire, M., Latimer, M., Eugène, F. & Jackson, P. L. Perception of pain in others: implication for caregivers. Pain Manag. 1, 257–265 (2011).

(3) Jackson, P. L., Meltzoff, A. N. & Decety, J. How do we perceive the pain of others? A window into the neural processes involved in empathy. Neuroimage 24, 771–779 (2005).

(4) Krishnan, A. et al. Somatic and vicarious pain are represented by dissociable multivariate brain patterns. Elife 5, (2016).

(5) Possidónio, C., Graça, J., Piazza, J. & Prada, M. Animal Images Database: Validation of 120 Images for Human-Animal Studies. Anim. an open access J. from MDPI 9, (2019).

(6) Amiot, C. E. & Bastian, B. Toward a psychology of human-animal relations. Psychol. Bull. 141, 6–47 (2015).

Presenting Author

Maria Suñol

Poster Authors

Maria Suñol, PhD

PhD

University of Barcelona

Lead Author

Brock Bastian

PhD

University of Melbourne

Lead Author

Marina López-Sola

Phd

University of Barcelona

Lead Author

Topics

  • Mechanisms: Psychosocial and Biopsychosocial