Journal Article

Medial entorhinal cortex and medial septum contribute to self-motion-based linear distance estimation

Gordillo-Salas, Marta, Jacob, Pierre-Yves, Facchini, Justine, Sargolini, Francesca, Poucet, Bruno, Save, Etienne

2017

Overview

Path integration is a navigation strategy that requires animals to integrate self-movements during exploration to determine their position in space. The medial entorhinal cortex (MEC) has been suggested to play a pivotal role in this process. Grid cells, head-direction cells, border cells as well as speed cells within the MEC collectively provide a dynamic representation of the animal position in space based on the integration of self-movements. All these cells are strongly modulated by theta oscillations, thus suggesting that theta rhythmicity in the MEC may be essential for integrating and coordinating self-movement information during navigation. In this study, we first show that excitotoxic MEC lesions, but not dorsal hippocampal lesions, impair the ability of rats to estimate linear distances based on self-movement information. Next, we report similar deficits following medial septum inactivation, which strongly impairs theta oscillations in the entorhinal–hippocampal circuits. Taken together, these findings demonstrate a major role of the MEC and MS in estimating distances to be traveled, and point to theta oscillations within the MEC as a neural mechanism responsible for the integration of information generated by linear self-displacements.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V,Springer Verlag
• Subject: Animals / Behavior, Animal - drug effects / Biomedical and Life Sciences / Biomedicine / Cell Biology / Circuits / Cognitive science / Cortex (entorhinal) / Entorhinal Cortex - drug effects / Entorhinal Cortex - pathology / Entorhinal Cortex - physiopathology / Excitatory Amino Acid Agonists - toxicity / Excitotoxicity / Exploration / GABA-A Receptor Agonists - toxicity / Hippocampus / Hypothalamus - drug effects / Hypothalamus - pathology / Hypothalamus - physiopathology / Ibotenic Acid - toxicity / Integration / Locomotion - drug effects / Male / N-Methylaspartate - toxicity / Navigation behavior / Neurology / Neuroscience / Neurosciences / Original Article / Rats, Long-Evans / Rodents / Self / Septum / Space Perception - drug effects / Spatial Navigation - drug effects / Spatial Processing - drug effects / Theta Rhythm - drug effects / Theta rhythms