title: Restoring Latent Visual Working Memory Representations in Human Cortex.
abstract: Working memory (WM) enables the storage and manipulation of limited amounts of information over short periods. Prominent models posit that increasing the number of remembered items decreases the spiking activity dedicated to each item via mutual inhibition, which irreparably degrades the fidelity of each item's representation. We tested these models by determining if degraded memory representations could be recovered following a post-cue indicating which of several items in spatial WM would be recalled. Using an fMRI-based image reconstruction technique, we identified impaired behavioral performance and degraded mnemonic representations with elevated memory load. However, in several cortical regions, degraded mnemonic representations recovered substantially following a post-cue, and this recovery tracked behavioral performance. These results challenge pure spike-based models of WM and suggest that remembered items are additionally encoded within latent or hidden neural codes that can help reinvigorate active WM representations.
authors: Neurosciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA. Electronic address: tsprague@nyu.edu.
authors: Thomas C
authors: TC
authors: Sprague
authors: Department of Psychology, University of California, San Diego, La Jolla, CA 92093, USA.
authors: Edward F
authors: EF
authors: Ester
authors: Neurosciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA; Department of Psychology, University of California, San Diego, La Jolla, CA 92093, USA; Kavli Institute for Brain and Mind, University of California, San Diego, La Jolla, CA 92093, USA. Electronic address: jserences@ucsd.edu.
authors: John T
authors: JT
authors: Serences
mesh_terms: D001931:Brain Mapping; D003463:Cues; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008570:Memory, Short-Term / Q000502:physiology*; D010775:Photic Stimulation; D065852:Spatial Memory / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*