Shared and distinct functional networks for empathy and pain processing: a systematic review and meta-analysis of fMRI studies

Abstract

Background: Empathy for pain is a complex phenomenon incorporating sensory, cognitive and affective processes. Functional neuroimaging studies indicate a rich network of brain activations for empathic processing. However, previous research focused on core activations in bilateral anterior insula (AI) and anterior cingulate/anterior midcingulate cortex (ACC/aMCC) which are also typically present during nociceptive (pain) processing. Theoretical understanding of empathy would benefit from empirical investigation of shared and contrasting brain activations for empathic and nociceptive processing.

Method: Thirty-nine empathy for observed pain studies (1112 participants; 527 foci) were selected by systematic review. Coordinate based meta-analysis (activation likelihood estimation) was performed and novel contrast analyses compared neurobiological processing of empathy with a comprehensive meta-analysis of 180 studies of nociceptive processing (Tanasescu et al., 2016).

Results: Conjunction analysis indicated overlapping activations for empathy and nociception in AI, aMCC, somatosensory and inferior frontal regions. Contrast analysis revealed increased likelihood of activation for empathy, relative to nociception, in bilateral supramarginal, inferior frontal and occipitotemporal regions. Nociception preferentially activated bilateral posterior insula, somatosensory cortex and aMCC.

Conclusion: Our findings support the likelihood of shared and distinct neural networks for empathic, relative to nociceptive, processing. This offers succinct empirical support for recent tiered or modular theoretical accounts of empathy.

Keywords: activation likelihood estimation; neuroimaging; perception action model.

Fig. 1

Flow chart depicting the initial search and eligibility screening process.

Fig. 2

The location of significant ALE clusters from the meta-analysis of concordant activations for empathy for pain. Results are displayed overlaid onto a standardized MNI template anatomical brain in (A). 3D surface projection. (B) As a montage of coronal slices throughout the whole brain. ALE scores are indicated by colourbar.

Fig. 3

The location of significant clusters from conjunction analysis of ALE maps for empathy for pain and directly perceived pain. Results are displayed overlaid onto standardized MNI template anatomical brain in (A). 3D surface projection. (B) As a montage of coronal slices throughout the whole brain. ALE scores are indicated by colourbar.

Fig. 4

The location of significant clusters from contrast analysis of ALE maps for greater likelihood of empathy for pain relative to directly perceived pain and vice versa. Results in green indicate regions which showed greater likelihood of concordance of activation for empathy for pain, but not for direct pain experience. Results in blue indicate regions which showed greater likelihood of concordance of activation for direct pain experience, but not for empathy for pain. All clusters are overlaid onto standardized MNI template anatomical brain in (A). 3D surface projection. (B). As a montage of coronal slices throughout the whole brain. Relative Z scores are indicated by colourbar.