Working Memory Within The Visual Dorsal Stream: Brain Potentials of Spatial Location and Motion Direction Encoding Into Memory

Abstract

Recently, evidence of two different working memory subsystems for visual information has been found, these subsystems corresponding to the two main visual pathways: the dorsal stream for motion-spatial information and the ventral stream for object information. This study aimed further to dissociate different working memory subsystems within one of the streams, namely within the dorsal stream. For these purposes, event-related potentials (ERP) were recorded while subjects memorized either the spatial location or the motion direction of stimuli. These ERPs were compared to ERPs recorded while subjects looked at the same stimuli but performed other control, nonmemory tasks. Results revealed an important difference in ERP modulation between a working memory subsystem for spatial location and another subsystem for motion direction, providing evidence of different working memory subsystems within the dorsal stream.

Keywords:

• Event-related potentials
• working memory
• spatial location
• motion
• visual