The brain's grid and place cells, which contribute to spatial representations of the external environment, are thought to be modulated by the hyperpolarization-activated cation current (I(h)). Giocomo et al. and Hussaini et al. now provide new insights into these cells' unique activity patterns by studying transgenic mice lacking I(h).

Many animals, on air, water, or land, navigate in three-dimensional (3D) environments, yet it remains unclear how brain circuits encode the animal's 3D position. We recorded single neurons in freely flying bats, using a wireless neural-telemetry system, and studied how hippocampal place cells encode 3D volumetric space during flight. Individual place cells were active in confined 3D volumes, an...

The hippocampus is essential for learning complex spatial relationships, but little is known about how hippocampal neural activity changes as animals learn about a novel environment. We studied the formation of new place representations in rats by examining the changes in place-specific firing of neurons in the CA1 region of the hippocampus and the relationship between these changes and behavio...

Neurons make contacts with each other by synapses: The presynaptic neuron sends its output to the synapse via an axon, and the postsynaptic neuron receives it via its dendritic tree (“dendrite”). Most neurons produce their output in form of virtually binary events (action potentials or spikes). Some classes of neurons (e.g., in the retina) nevertheless do not generate spikes but show continuous...

This work was supported by TUBITAK 1001 program (no:118E722), Isik University BAP (No: 16A202), and NVIDIA hardware donation of a Tesla K40 GPU unit.

The hippocampal formation is necessary for spatial learning and memory in rats. One aspect of this cognitive function, the ability to remember path sequences, is thought to be achieved through phase precession. The two components of phase precession are a strong theta rhythm (8-12 Hz) in the local field potential and place-selective neurons, which fire selectively while the rat is in a particul...

Accurate spatial localization requires a mechanism that corrects for errors, which might arise from inaccurate sensory information or neuronal noise. In this paper, we propose that Hippocampal place cells might implement such an error correction mechanism by integrating different sources of information in an approximately Bayes-optimal fashion. We compare the predictions of our model with physi...

Hippocampal place cells fire at different rates when a rodent runs through a given location on its way to different destinations. However, it is unclear whether such firing represents the animal's intended destination or the execution of a specific trajectory. To distinguish between these possibilities, Lister Hooded rats (n = 8) were trained to navigate from a start box to three goal locations...

Land change science has demonstrated that rural livelihoods around the world both drive and reflect changing environmental regimes and political economic/ structural transformations. This article explores the relationship between increasingly globalized rural livelihoods and in-place land change, assessing results from social surveys of smallholding households in the southern Yucatán region. We...