Distinct neural correlates of the preference-related valuation of supraliminally and subliminally presented faces.

Recent neuroimaging studies have investigated the neural substrates involved in the valuation of supraliminally presented targets and the subsequent preference decisions. However, the neural mechanisms of the valuation of subliminally presented targets, which can guide subsequent preference decisions, remain to be explored. In the present study, we determined whether the neural systems associated with the valuation of supraliminally presented faces are involved in the valuation of subliminally presented faces. The subjects were supraliminally and subliminally presented with faces during functional magnetic resonance imaging (fMRI). Following fMRI, the subjects were presented with pairs of faces and were asked to choose which face they preferred. We analyzed brain activation by back-sorting the fMRI data according to the subjects' choices. The present study yielded two main findings. First, the ventral striatum and the ventromedial prefrontal cortex predict preferences only for supraliminally presented faces. Second, the dorsomedial prefrontal cortex may predict preferences for subliminally presented faces. These findings indicate that neural correlates of the preference-related valuation of faces are dissociable, contingent upon whether the subjects consciously perceive the faces.