Hemispheric asymmetries in image-specific and abstractive priming of famous faces: evidence from reaction times and event-related brain potentials

We investigated hemispheric differences in image-specific and abstractive immediate repetition priming of famous faces. Participants performed speeded familiarity decisions for centrally presented famous and unfamiliar target faces. Target faces were preceded by lateralized primes (150 ms), presented either in the left or right visual field (LVF or RVF). Primes were either an identical photograph of the famous target face (image-specific priming), a different image of the famous target face (abstractive priming) or a different familiar face (unprimed condition). Reaction times (RTs) revealed significant effects of priming for both image-specific and abstractive priming overall. In addition, image-specific priming was more than twice the magnitude for targets following LVF primes as compared to RVF primes. By contrast, no hemispheric differences emerged for abstractive face priming across different images. Whereas ERPs revealed no evidence that priming affected the N170 component, both image-specific and abstractive priming significantly modulated the amplitudes of a right temporal N250r and a parietal N400 component. Behavioural and electrophysiological evidence for hemispheric differences in image-specific and abstractive face priming are discussed with respect to current theories of how the human left and right ventral temporal cortices represent abstractive and form-specific visual information.