Causal manipulation of self-other mergence in the dorsomedial prefrontal cortex

To navigate social environments, people must simultaneously hold representations about their own and others' abilities. During self-other mergence, people estimate others' abilities not only on the basis of the others' past performance, but the estimates are also influenced by their own performance. For example, if we perform well, we overestimate the abilities of those with whom we are co-operating and underestimate competitors. Self-other mergence is associated with specific activity patterns in the dorsomedial prefrontal cortex (dmPFC). Using a combination of non-invasive brain stimulation, functional magnetic resonance imaging, and computational modeling, we show that dmPFC neurostimulation silences these neural signatures of self-other mergence in relation to estimation of others' abilities. In consequence, self-other mergence behavior increases, and our assessments of our own performance are projected increasingly onto other people. This suggests an inherent tendency to form interdependent social representations and a causal role of the dmPFC in separating self and other representations.

Automated summary

In social environments, people estimate others' abilities based on their own and others' past performance, with specific neural patterns in the dmPFC associated with self-other mergence behavior. Research shows that neurostimulation of the dmPFC can silence these neural signatures, leading to increased self-other mergence behavior and projection of self-assessments onto others. This suggests a tendency to form interdependent social representations and highlights the role of the dmPFC in separating self and other representations.