Topological mapping of space in bat hippocampus

Mammalian hippocampus plays a key role in spatial learning and memory, but the exact nature of the hippocampal representation of space is still being explored. Recently, there has been a fair amount of success in modeling hippocampal spatial maps in rats, assuming a topological perspective on spatial information processing. In this paper, we use the topological model to study 3D learning in bats, which produces several insights into neurophysiological mechanisms of the hippocampal spatial mapping. First, we demonstrate functional importance of the cell assemblies for producing accurate maps of the 3D environments. Second, the model suggests that the readout neurons in these cell assemblies should function as integrators of synaptic inputs, rather than detectors of place cells’ coactivity and allows estimating the integration time window. Lastly, the model suggests that, in contrast with relatively slow moving rats, suppressing θ-precession in bats improves the place cells capacity to encode spatial maps, which is consistent with the experimental observations.