Empathy for Pain Involves the Affective but not Sensory Components of Pain

1. Tania Singer,1 Ben Seymour,1 John O’Doherty,1 Holger Kaube,2Raymond J. Dolan,1 ChrisD. Frith1 Empathy for Pain Involves theAffective but not SensoryComponents of Pain

2. Empathy Understand other peoples' emotional or sensory states Understanding others' mental states is important for social interaction • “Theory of mind” • Understand other peoples' cognitive states • e.g. Sally-Anne test

3. Empathy • Preston and de Wall's model

4. Past studies of empathy • Watch videos of others telling sad, happy, or neutral stories accompanied by sad or happy expressions • Imitating vs. observing sad and happy faces • Responses to smelling aversive or pleasant odors compared to watching videos of other people smelling those odors

5. Past Studies of empathy • Results: • Latter two studies found activation in same areas when watching an emotion and experiencing or imitating it • “Emotional contagion”

6. Methods • 16 couples • Female partner sees her and her partners' hands and screen with cues • Cues indicate whether herself or her partner will receive high (painful) or low (not painful) stimulation

7. Methods • Demonstrates empathy without exposure to an emotional cue • Subjects don't see partner's face • Only know of emotional state though neutral cues

8. Methods • After scanning, subjects respond to questions about: • Pain intensity • Unpleasantness • Empathy (“Balanced Emotional Empathy Scale” and “Empathic Concern Scale”)

9. Methods • Pain intensity questionnaire confirms that low stimulus isn't painful but high stimulus is • Unpleasantness confirms that subjects are empathizing with their partners • “other” and “self” trials with pain were both rated as more unpleasant than those without pain • Difference between “pain” and “no pain” trials was significant at p < .001, difference between self and other trials had p = .73, not significant

10. “Self” trials: pain vs. no pain • “Pain matrix” • SI/MI • SII • Bilateral mid and anterior insula • ACC • Right ventrolateral and mediodorsal thalumus • Brainstem • Mid and right lateral cerebellum

11. Areas activated by pain trials for both “self” and “other” • Caudal and posterior rostral ACC • Bilateral middle insula and anterior insula • Brainstem • Lateral cerebellum

12. Time course of activation • Time courses of peak activation during self (green lines) and other (red lines) • Authors suggest two peaks • Anticipation upon seeing cue and actual receipt of pain?

13. Activation only during “other” pain trials Extrastriate areas associated with vision “Self” vs. “other” pain trials • Differential activation in “self” trials with pain but not “other” trials • SI/MI • SII/posterior insula • Part of caudal ACC

14. “Self” trials • Differential activation in “self” trials with pain but not “other” trials • SI/MI • SII/posterior insula • Part of caudal ACC

15. Time Course • Only one peak (late) in activation • Receipt of pain? • Sensory components of pain not triggered by cue

16. In which areas does pain-related activation correlate with individual empathy? • Individual empathy assessed with two questionnaires • Balanced Emotional Empathy Scale • Empathic Concern Scale

17. In which areas does pain-related activation correlate with empathy? • Areas with significant correlation: • Posterior rostral ACC • Left, but not right, anterior insula • Part of anterior ACC • Lateral right cerebellum

18. ACC and left AI

19. Rostral ACC • Previous report on a precingulotomy patient • Single neuron recordings in ACC respond both to painful stimuli and observing or anticipating delivery of painful stimulus to experimenter

20. Sensory v. Affective components of pain? • Possible interpretation • self-specific areas in the pain matrix are associated with sensory components of pain • Areas active in empathy condition are associated with affective, subjective components of pain

21. Sensory v. Affective components of pain? • Makes intuitive sense, but is there any more evidence for this interpretation?

22. Sensory v. Affective components of pain? • SI, parts of SII, posterior insula, and lateral thalmus have contralaterally biased representations of painful stimulus • Suggests that these regions may provide sensory information such as location, quality, and intensity of the pain • AI and ACC do not show contralateral bias

23. Sensory v. Affective components of pain? • Studies using hypnosis to dissociate sensory from affective pain components • Posterior rostral ACC modulated by reported unpleasantness • SI and SII unaffected by unpleasantness • Similar results from using attentional manipulations (ACC activation modulated, SII not)

24. Sensory v. Affective components of pain? • Anticipation of pain activates more anterior insular regions, experience of pain modulates more posterior regions • Implicates anterior insula in affective experience of pain, posterior insula in sensory experience

25. Sensory v. Affective components of pain? • Subjective pain reduction in placebo and opioid analgesia • Increased rostral ACC and right AI activation

26. Conclusions • Rostral ACC and AI reflect emotional response to pain • Pain as one of the homeostatic emotions • AI and ACC also involved in representing internal bodily states • In many studies, activation in AI and ACC correlated with positive/negative subjective feelings • “Second order representations of bodily homeostatic states”

27. Conclusions • Authors conclude that the ability to empathize may have evolved from a system for representing internal states, including subjective feeling states