Electrocortical evidence for the time course processes of attentional bias toward infant faces

Abstract

Previous behavioral studies have demonstrated that adults show initial orientation toward neutral infant faces compared to neutral adult faces. However, it is unclear whether the initial orientation toward infant faces is sustained and whether attentional bias toward infant faces exists under different emotional valences. In the present study, event-related potentials were recorded while nulliparous women performed a dot-probe task to identify the time course processes involved in attentional bias toward infant faces. Three face pair types were used in the task; each face pair type contained one infant facial expression (happy, neutral, or sad) and one adult facial expression with the same emotional valence. An early N2pc was observed for each face pair type, which suggests that there was initial orientation toward infant faces irrespective of emotional valence. The absence of sustained posterior contralateral negativity in all face pair types indicated that attentional orientation was not sustained at the later stage of attentional selection. In addition, an inverted late N2pc was observed for the happy face pairs and may reflect a “happy superiority effect” in attentional selection processing.