Neuronal encoding of complex three-dimensional environments (360G-Wellcome-211804_Z_18_Z)

This proposed research intends to investigate the brain representation of complex, multilayered three-dimensional environments in free-roaming rodents by detecting electrical neuronal activities. With the assumption that the grid cell can form a lattice representation in a volumetric space, the main goal of this project is to test this hypothesis and construct more detailed mosaic neuronal models. From the previous experimental evidence, the grid cell plays a pivotal role in distance-measuring by forming a grid-like array on a flat surface, however, how this array is remodelled in vertical or tilled surface remains debatable. In this project, rats will be allowed to explore in a giant lattice model with options of climbing up or down, dwelling forwards or backwards while looking for rewards. The neuronal activities in rat's hippocampus will be collected, reconstructed into a 3D model. If the hypothesis is to be correct, the 3D cognition map is suggested to be a multiple evenly-spaced neuron filed distributed volumetrically (figure1, D and E). Otherwise, the field might be distributed in parallel columns vertical to the ground, as the extension of the 2D hexagonal array (figure 1, C).