title: The spatial periodicity of grid cells is not sustained during reduced theta oscillations.
abstract: Grid cells in parahippocampal cortices fire at vertices of a periodic triangular grid that spans the entire recording environment. Such precise neural computations in space have been proposed to emerge from equally precise temporal oscillations within cells or within the local neural circuitry. We found that grid-like firing patterns in the entorhinal cortex vanished when theta oscillations were reduced after intraseptal lidocaine infusions in rats. Other spatially modulated cells in the same cortical region and place cells in the hippocampus retained their spatial firing patterns to a larger extent during these periods without well-organized oscillatory neuronal activity. Precisely timed neural activity within single cells or local networks is thus required for periodic spatial firing but not for single place fields.
authors.affiliation: Neurobiology Section and Center for Neural Circuits and Behavior, Division of Biological Sciences, University of California, San Diego, USA.
authors.forename: Julie
authors.initials: J
authors.lastname: Koenig
authors.forename: Ashley N
authors.initials: AN
authors.lastname: Linder
authors.forename: Jill K
authors.initials: JK
authors.lastname: Leutgeb
authors.forename: Stefan
authors.initials: S
authors.lastname: Leutgeb
mesh_terms: D000818:Animals; D018728:Entorhinal Cortex / Q000166:cytology / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D008012:Lidocaine / Q000494:pharmacology; D008297:Male; D008564:Membrane Potentials; D009043:Motor Activity; D009415:Nerve Net / Q000502:physiology; D009434:Neural Pathways; D009474:Neurons / Q000502:physiology*; D010507:Periodicity; D051381:Rats; D020318:Rats, Long-Evans; D012688:Septum Pellucidum / Q000187:drug effects / Q000502:physiology; D013028:Space Perception; D013826:Theta Rhythm / Q000187:drug effects
chemical_list: D008012:Lidocaine