Research paperPerceiving emotions in human-human and human-animal interactions: Hemodynamic prefrontal activity (fNIRS) and empathic concern

- Empathic responses to human-human and human-animal interactions were explored.
- Changes in O2Hb and HHb over prefrontal sites were examined.
- Conflictual HH and cooperative HA interactions resulted as the most salient.
- BA9 response to negative HH stimuli was directly related to empathic trait.
- BA46 response to negative HA stimuli was inversely related to empathic trait.

In the last years social neuroscience research attempted to identify the neural networks underlying the human ability to perceive others' emotions, a core process in establishing meaningful social bonds. A large amount of papers arose and identified common and specific empathy-based networks with respect to stimulus type and task. Despite the great majority of studies focused on human-human contexts, we do not establish relations with only other humans, but also with non-human animals. The aim of the present work was to explore the brain mechanisms involved in empathic concern for people who interacts with both peers and other species. Participants have been assessed by functional near-infrared spectroscopy (fNIRS) while viewing pictures depicting humans interacting with both other men and women (human-human condition: HH), or with dogs and cats (human-animal: HA). Results showed that aggressive HH interactions elicited greater prefrontal activity (PFC) than HA ones while, when considering HA interactions, friendly ones were related to higher cortical activity. Finally, oxy (O2Hb) and deoxyhemoglobin (HHb) increasing related to the processing of aggressive interactions positively correlated with different empathic measures, within more specific brain regions. Results were elucidated with respect to available evidence on emotion perception, empathic neural mechanisms and their functional meaning for human-animal contexts.