The maps inside your head: How the brain represents sensory and cognitive spaces

In many functionally distinct regions of the brain, populations of neurons form maps of sensory and cognitive spaces. I will explain a physicist's approach to this neural topography of information. First, I will review the brain's architecture. Next, I will present evidence from the early visual system that the brain minimizes the neural resources required to reach the fidelity necessary to represent stimuli, given an animal's behavioral needs. I will then apply this principle of efficiency to the "sense of place" -- i.e., the representation of an animal's physical location in the "place cell" and "grid cell" systems, which have been discovered in two brain areas, the hippocampus and the entorhinal cortex. I will conclude by discussing how similar analyses broadly illuminate the organization of the brain.