Spatial cognition in bats and rats: from sensory acquisition to multiscale maps and navigation

Abstract

Spatial orientation and navigation rely on the acquisition of several types of sensory information. This information is then transformed into a neural code for space in the hippocampal formation through the activity of place cells, grid cells and head-direction cells. These spatial representations, in turn, are thought to guide long-range navigation. But how the representations encoded by these different cell types are integrated in the brain to form a neural 'map and compass' is largely unknown. Here, we discuss this problem in the context of spatial navigation by bats and rats. We review the experimental findings and theoretical models that provide insight into the mechanisms that link sensory systems to spatial representations and to large-scale natural navigation.

Spatial representation in the hippocampal formation: a history

“…If the latter is true, how are the map fragments connected? And how is space coded in large and threedimensional environments 277 ? In flying bats, place cells have spherical firing fields 279 and head direction cells are tuned to all three axes of orientation 220 .…”

“…Ultimately, studies of the hippocampal-entorhinal circuit should explore how cells map environments of shapes, sizes, and content more comparable to the animal's natural habitat 277 . Are grid cells, head direction cells, and place cells used only for local mapping, in the range of a few meters, or is the entorhinal-hippocampal network used also for extended spaces, and if so, how?…”

Development of site fidelity in the nocturnal amblypygid, Phrynus marginemaculatus

“…The subject in Fig. 7e was observed to move circuitously across the center of the arena and then enter the HS which is reminiscent of paths associated with the use of a beacon (Geva-Sagiv et al 2015). This individual performed what appears to be a type of spiral search similar to olfactory-guided behavior observed in other animals (Vickers 2000;Calhoun et al 2014;Svensson et al 2014).…”

Long-range navigation by path integration and decoding of grid cells in a neural network

“…bats that forage across distances up to kilometers away from the nest [16]. However, the fact that there are multiple grid modules in the brain might provide a solution.…”