The entorhinal cortex is the interface between the hippocampus and the rest of neocortex. Allocentric signals can modify the spatial map representation in the hippocampus through the entorhinal cortex. In this last structure there exist grid cells that can represent the space as accurately as the hippocampal place cells. It is arguable that hippocampal place cells, presubiculum head direction cells and the entorhinal grid cells acting in concert are necessary for, and contribute to the correct spatial navigation, in such a way that in the absence of any of them, navigation is still possible, but with lower accuracy. My current interest is to study if self-motion sensory information (ambulatory signals, visual signals or vestibular signals) is responsible for configuring the spatial representation of entorhinal grid cells. We study how sensory information such as visual landmarks can modify or reconfigure the spatial map representation in the hippocampus, through the entorhinal cortex, and how the hippocampal cell activity can modulate the properties of entorhinal grid cell, using extracellular electrophysiological recording in freely moving rats, during a spatial navigation task or a spatial memory task.