Investigating the familiarity effect in texture segmentation by means of event-related brain potentials

The familiarity effect (FE) refers to the phenomenon that it is easier to find an unfamiliar element on a background of familiar elements than vice versa. In this study, we examined the FE in texture segmentation while recording event-related brain potentials with the aim to find out which processing stages were influenced by familiarity. In two experiments, with different levels of texture homogeneity, the N1, the N2p, and the P3 components were investigated. It was found that the FE in texture segmentation is associated with a modulation of the early N1 and of the intermediate N2p component for homogeneous textures. For inhomogeneous (jittered) textures, the FE was found for the intermediate N2p and for the late P3 components, but not for the N1 component. Our findings suggest that increasing texture inhomogeneity shifts the FE occurrence to later processing stages.