Spatial reorganization of object representations in high-level visual cortex distinguishes working memory from perception.

Abstract

The visual system balances veridical object perception with flexible visual working memory (VWM), both engaging high-level visual regions. However, how these competing demands shape object-selective cortex (OSC) representations remains unclear. Here, we ask whether VWM inherits the spatial constraints observed in the OSC during perception or reorganizes representations to meet mnemonic demands. Using a matched task design and functional magnetic resonance imaging-based decoding, we systematically compared the localization of object-identity representations during perception and VWM. A robust dissociation emerged: Perception kept object information largely contralateral, whereas VWM produced robust ipsilateral representation even when memorizing bilateral items. These expanded representations exploited more than 90% of ipsilateral OSC vertices and could not be attributed to increased attentional span. Critically, the ipsilateral representations closely mirrored contralateral representations, implicating interhemispheric coordination in VWM. Together, these findings demonstrate that object VWM flexibly recruits distributed high-level visual cortex, with spatial reorganization distinguishing mnemonic flexibility from perceptual fidelity.