Anisotropic encoding of three-dimensional space by place cells and grid cells

Although the encoding of horizontal space by place and grid cells is relatively well understood, the manner by which these neurons encode height is not yet known. Here, the authors find that place cell sensitivity to height is weaker than for horizontal distances, and grid cell firing is aperiodic in the vertical dimension, suggesting absent odometry for height. It therefore appears that, in the mammalian brain, volumetric space is not encoded uniformly in all dimensions.