Social attention and the ventromedial prefrontal cortex.

Imagine looking out over the patrons in a restaurant as one of them looks up from their plate of food and makes eye contact with you. The change in the visual image on your retina is miniscule, yet the knowledge gained is great. A tiny change in the movements of another person’s eyes lets you know instantly that they are looking at you, know that you are also looking at them, and feel a particular emotion or have a particular intention. In this issue of Brain, Wolf et al. (2014) describe three patients with focal lesions of the ventromedial prefrontal cortex (vmPFC) who show strikingly atypical patterns of fixation onto faces: they do not look at a person’s eyes, with implications for social decision-making. The eye region of faces is salient not only because it tells us where somebody else is directing their attention, but also because it informs us of their emotional state (the muscles around the eyes contribute substantially to certain emotional facial expressions, most particularly fear). Deficits in our ability to process this information may underlie aspects of paranoid schizophrenia (feeling as though somebody is watching you all the time) as well as autism spectrum disorders (where diminished eye contact is associated with social disengagement; Fig. 1). The ability to use our perception of another person’s gaze to guide our own attention emerges during specific stages of early development, and some aspects of this ability may be unique to humans (although dogs are also quite good at figuring out social attention signals). To understand these different facets of social attention, it is a high priority to elucidate the neural substrates involved.