Activation timecourse of ventral visual stream object-recognition areas: high density electrical mapping of perceptual closure processes.

Object recognition is achieved even in circumstances when only partial information is available to the observer. Perceptual closure processes are essential in enabling such recognitions to occur. We presented successively less fragmented images while recording high-density event-related potentials (ERPs), which permitted us to monitor brain activity during the perceptual closure processes leading up to object recognition. We reveal a bilateral ERP component (N(cl)) that tracks these processes (onsets approximately 230 msec, maximal at approximately 290 msec). Scalp-current density mapping of the N(cl) revealed bilateral occipito-temporal scalp foci, which are consistent with generators in the human ventral visual stream, and specifically the lateral-occipital or LO complex as defined by hemodynamic studies of object recognition.