title: Laminar Module Cascade from Layer 5 to 6 Implementing Cue-to-Target Conversion for Object Memory Retrieval in the Primate Temporal Cortex.
abstract: The cerebral cortex computes through the canonical microcircuit that connects six stacked layers; however, how cortical processing streams operate in vivo, particularly in the higher association cortex, remains elusive. By developing a novel MRI-assisted procedure that reliably localizes recorded single neurons at resolution of six individual layers in monkey temporal cortex, we show that transformation of representations from a cued object to a to-be-recalled object occurs at the infragranular layer in a visual cued-recall task. This cue-to-target conversion started in layer 5 and was followed by layer 6. Finally, a subset of layer 6 neurons exclusively encoding the sought target became phase-locked to surrounding field potentials at theta frequency, suggesting that this coordinated cell assembly implements cortical long-distance outputs of the recalled target. Thus, this study proposes a link from local computation spanning laminar modules of the temporal cortex to the brain-wide network for memory retrieval in primates.
authors.affiliation: Department of Physiology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Kenji W
authors.initials: KW
authors.lastname: Koyano
authors.affiliation: Department of Physiology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan. Electronic address: mtakeda-ns@umin.ac.jp.
authors.forename: Masaki
authors.initials: M
authors.lastname: Takeda
authors.affiliation: Department of Physiology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Teppei
authors.initials: T
authors.lastname: Matsui
authors.affiliation: Department of Physiology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Hirabayashi
authors.affiliation: Department of Physiology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Ohashi
authors.affiliation: Department of Physiology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan; Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo 113-8421, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency (JST), Kawaguchi, Saitama 332-0012, Japan. Electronic address: yasushi_miyashita@m.u-tokyo.ac.jp.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Miyashita
mesh_terms: D000818:Animals; D001244:Association; D002540:Cerebral Cortex / Q000502:physiology; D003463:Cues; D004569:Electroencephalography; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory; D011939:Mental Recall / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D013702:Temporal Lobe / Q000502:physiology*
keywords: MRI; cortical layer; laminar localization; memory retrieval; microcircuit; monkey; temporal cortex