Grid-cell representations in mental simulation

• Published in: eLife Vol. 5
• Main Authors: Bellmund, Jacob Ls, Deuker, Lorena, Navarro Schröder, Tobias, Doeller, Christian F
• Format: Journal Article
• Language: English
• Published: England eLife Sciences Publications Ltd 30-08-2016; eLife Sciences Publications, Ltd
• Subjects: Action Potentials; Adolescent; Adult; Brain; Brain mapping; Cortex (entorhinal); Entorhinal Cortex - physiology; fMRI; Functional magnetic resonance imaging; grid cells; Grid Cells - physiology; Humans; Imagination; Magnetic Resonance Imaging; Male; Models, Neurological; navigation; Navigation behavior; Neuroscience; Neurosciences; Parahippocampal gyrus; Parahippocampal Gyrus - physiology; planning; Simulation; Space Perception; spatial cognition; Spatial Memory; Spatial Navigation; Young Adult; fMRI; planning; navigation; neuroscience; grid cells; spatial cognition; imagination; human
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/eLife.17089

Anticipating the future is a key motif of the brain, possibly supported by mental simulation of upcoming events. Rodent single-cell recordings suggest the ability of spatially tuned cells to represent subsequent locations. Grid-like representations have been observed in the human entorhinal cortex during virtual and imagined navigation. However, hitherto it remains unknown if grid-like representations contribute to mental simulation in the absence of imagined movement. Participants imagined directions between building locations in a large-scale virtual-reality city while undergoing fMRI without re-exposure to the environment. Using multi-voxel pattern analysis, we provide evidence for representations of absolute imagined direction at a resolution of 30° in the parahippocampal gyrus, consistent with the head-direction system. Furthermore, we capitalize on the six-fold rotational symmetry of grid-cell firing to demonstrate a 60° periodic pattern-similarity structure in the entorhinal cortex. Our findings imply a role of the entorhinal grid-system in mental simulation and future thinking beyond spatial navigation.