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

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

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. “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
Activation only during “other” pain trials
Extrastriate areas associated with vision

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