Observing social interactions: the effect of gaze.

Our social abilities depend on specialized brain systems that allow us to perform crucial operations such as interpreting the actions of others. This functional magnetic resonance imaging (fMRI) study investigated whether human brain activity evoked by the observation of social interactions is modulated by gaze. During scanning participants observed social or individual actions performed by agents whose gaze could be either available or masked. Results demonstrated that the observation of social interactions evoked activity within a dorsal sector of the medial prefrontal cortex (MPFC), an area classically involved in social cognition. Importantly, activity within this area was modulated by whether the gaze of the agents performing the observed action was or was not available. The implications of these findings for a role played by the dorsal medial prefrontal cortex (dMPFC) in terms of inferential processes concerned with social interactions are considered.