title: Impaired hippocampal rate coding after lesions of the lateral entorhinal cortex.
abstract: In the hippocampus, spatial and non-spatial parameters may be represented by a dual coding scheme, in which coordinates in space are expressed by the collective firing locations of place cells and the diversity of experience at these locations is encoded by orthogonal variations in firing rates. Although the spatial signal may reflect input from medial entorhinal cortex, the sources of the variations in firing rate have not been identified. We found that rate variations in rat CA3 place cells depended on inputs from the lateral entorhinal cortex (LEC). Hippocampal rate remapping, induced by changing the shape or the color configuration of the environment, was impaired by lesions in those parts of the ipsilateral LEC that provided the densest input to the hippocampal recording position. Rate remapping was not observed in LEC itself. The findings suggest that LEC inputs are important for efficient rate coding in the hippocampus.
authors.affiliation: Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, Trondheim, Norway. li.lu@ntnu.no
authors.forename: Li
authors.initials: L
authors.lastname: Lu
authors.forename: Jill K
authors.initials: JK
authors.lastname: Leutgeb
authors.forename: Albert
authors.initials: A
authors.lastname: Tsao
authors.forename: Espen J
authors.initials: EJ
authors.lastname: Henriksen
authors.forename: Stefan
authors.initials: S
authors.lastname: Leutgeb
authors.forename: Carol A
authors.initials: CA
authors.lastname: Barnes
authors.forename: Menno P
authors.initials: MP
authors.lastname: Witter
authors.forename: May-Britt
authors.initials: MB
authors.lastname: Moser
authors.forename: Edvard I
authors.initials: EI
authors.lastname: Moser
mesh_terms: D000200:Action Potentials; D000344:Afferent Pathways / Q000503:physiopathology; D000818:Animals; D056654:CA3 Region, Hippocampal / Q000503:physiopathology*; D003116:Color; D018728:Entorhinal Cortex / Q000187:drug effects / Q000293:injuries / Q000503:physiopathology*; D004777:Environment; D005106:Exploratory Behavior / Q000502:physiology; D008297:Male; D061212:Memory, Episodic; D016202:N-Methylaspartate / Q000633:toxicity; D009473:Neuronal Plasticity; D009474:Neurons / Q000502:physiology*; D009498:Neurotoxins / Q000633:toxicity; D018408:Patch-Clamp Techniques; D017966:Pyramidal Cells / Q000502:physiology; D051381:Rats; D020318:Rats, Long-Evans; D013028:Space Perception / Q000502:physiology*; D013037:Spatial Behavior / Q000502:physiology
chemical_list: D009498:Neurotoxins; D016202:N-Methylaspartate