Visual Learning in Human Object Recognition Areas: A Repetition Priming Study Using High-density Electrical Mapping

Abstract:
Abstract: Repetition priming is a facilitation of response due to repeated stimulus presentations. A case in point is the recognition of a previously uninterpretable version of a stimulus following exposure to the unambiguous stimulus. ERP recordings (64-channel) were used to investigate this visual learning. We recently reported a bilateral component (Ncl-290ms) that tracks object recognition processes as versions of an object are presented from most to least fragmented. Ncl was largest when recognition was achieved and was incrementally reduced in amplitude at the more fragmented levels prior to recognition (Doniger et al, in press). Scalp current density maps of Ncl localized it to scalp overlying lateral occipital (LO) complex-a system of areas implicated in object recognition. This study examined the effect of repetition priming on Ncl activity by repeating sequences of fragmented object images. We found robust Ncl-enhancement between initial and repeat presentations of identical highly fragmented images indicative of visual learning in LO, as interim perception of the complete object made recognition of these images possible. An early N1-enhancement over LO was found for repeat presentations, which may reflect access to the primed object representation.