It takes two to empathize: Interbrain coupling contributes to distress regulation.

While extant research on empathy has made significant progress in uncovering the mechanisms underlying the responses of an observer (empathizer) to the distress of another (target), it remains unclear how the interaction between the empathizer and the target contributes to distress regulation in the target. Here, we propose that behavioral and neural coupling during empathic interactions contribute to diminished distress. From November 2020 to November 2022, we recruited 37 pairs of previously unacquainted participants ( = 74) from multicultural backgrounds. They engaged in a 5 min face-to-face emotional sharing task, where one participant shared a distressing biographical experience with the other participant. We used functional near-infrared spectroscopy (fNIRS) to measure interbrain coupling in the emotion regulation system, specifically the dorsolateral prefrontal cortex (dlPFC), and the observation execution system, specifically the inferior frontal gyrus (IFG). Results indicate that during emotional sharing the target and the empathizer emotionally converge, such that the empathizer becomes sadder. Moreover, the levels of empathizers' empathy predicted both emotional convergence and target distress relief. The neuroimaging findings indicate that interbrain coupling in the dlPFC, IFG, and premotor cortex, predicted distress relief in the target, and more critically that interbrain coupling in the dlPFC played a mediating role in the relationship between distress relief and the levels of empathy of the empathizer. Considering the role of the dlPFC in emotion regulation, we conclude that interbrain coupling in this region during emotional sharing plays a key role in dyadic coregulation of distress. (PsycInfo Database Record (c) 2024 APA, all rights reserved).