Saccade direction encoding in the primate entorhinal cortex during visual exploration

• Type of Material: Article
• Authors: Nathaniel J. Killian, Georgia Institute of Technology; Elizabeth Buffalo, Emory University; Steve Potter, Emory University
• Language: English
• Date: 2015-12-22
• Publisher: National Academy of Sciences
• Publication Version: Final Published Version
• Copyright Statement: © 2015 National Academy of Sciences.
• Final Published Version (URL): http://dx.doi.org/10.1073/pnas.1417059112
• Title of Journal or Parent Work: PNAS: Proceedings of the National Academy of Sciences of the United States of America
• Volume: 112
• Issue: 51
• Start Page: 15743
• End Page: 15748
• Grant/Funding Information: Funding for this work was provided by National Institute of Mental Health Grants MH080007 (to E.A.B.) and MH093807 (to E.A.B.) and National Center for Research Resources Grant P51RR165 (currently Office of Research Infrastructure Programs/Office of the Director Grant P51OD11132).
• Keywords: Grid cells; Memory; Representation; medial temporal lobe; Projections; Thalamus; Science & Technology - Other Topics; Hippocampus; spatial representation; grid cell; Science & Technology; head direction; Neuronal activity; Presubiculum; Multidisciplinary Sciences; vision; Head direction; Monkeys
• Research Categories: Biology, Neuroscience; Biophysics, Medical; Biology, Physiology; Engineering, Biomedical

Abstract

We recently demonstrated that position in visual space is represented by grid cells in the primate entorhinal cortex (EC), suggesting that visual exploration of complex scenes in primates may employ signaling mechanisms similar to those used during exploration of physical space via movement in rodents. Here, we describe a group of saccade direction (SD) cells that encode eye movement information in the monkey EC during free-viewing of complex images. Significant saccade direction encoding was found in 20% of the cells recorded in the posterior EC. SD cells were generally broadly tuned and two largely separate populations of SD cells encoded future and previous saccade direction. Some properties of these cells resemble those of head-direction cells in rodent EC, suggesting that the same neural circuitry may be capable of performing homologous spatial computations under different exploratory contexts.