Pattern similarity and connectivity of hippocampal-neocortical regions support empathy for pain

Abstract

Empathy is thought to engage mental simulation, which in turn is known to rely on hippocampal-neocortical processing. Here, we tested how hippocampal-neocortical pattern similarity and connectivity contributed to pain empathy. Using this approach, we analyzed a data set of 102 human participants who underwent functional MRI while painful and non-painful electrical stimulation was delivered to themselves or to a confederate. As hypothesized, results revealed increased pattern similarity between fist-hand pain and pain empathy (compared to non-painful control conditions) within the hippocampus, retrosplenial cortex, the temporo-parietal junction and anterior insula. While representations in these regions were unaffected by confederate similarity, pattern similarity in the dorsal MPFC was increased the more dissimilar the other individual was perceived. Moreover, hippocampal connectivity with regions engaged in first-hand pain was also increased during pain empathy, during which hippocampal coupling with the fusiform gyrus positively scaled with self-report measures of individual perspective taking skills. These findings highlight that shared representations and interactions within a hippocampal-neocortical network support pain empathy. This potentially reflects memory-based mental simulation processes, which seem partially modulated by personality traits and the perceived similarity of the other individual in pain.