Social interaction modifies neural response to gaze shifts

Monitoring gaze shifts is important for social interactions.The direction of gaze can reveal intentions and help to predictfuture actions. Here we examined whether behavioural and neuralresponses to gaze shifts were modulated by the social contextof the gaze shift in two linked experiments. Two faces werepresented, one gazing directly at the subject (the ‘social’face) and one with averted gaze (the ’unsocial’face). One face then made a gaze shift that was either towardsa visible target (’correct’) or towards anotherlocation in space (’incorrect’). Both behaviouraland neural responses to gaze shifts were modulated by the socialcontext and the goal directedness of the gaze shift. Reactiontimes were significantly faster in response to ’correct’and ‘social’ compared with ’incorrect’and ’unsocial’ gaze shifts, respectively. Usingfunctional magnetic resonance imaging, we found significantlygreater activation in the parieto-frontal attentional network,and in some parts of the posterior superior temporal sulcus,in response to ‘incorrect’ and ’unsocial’compared with ’incorrect’ and ‘social’gaze shifts, respectively. Conversely, we found greater activationin the medial prefrontal cortex and precuneus in response to’correct’ and ‘social’ compared with’incorrect’ and ’unsocial’ gaze shifts.This activity may reflect the experience of joint attentionassociated with these gaze shifts.