I will introduce key aspects of the problem of navigation and describe circuits in the brain that participate in navigational computations. These circuits contain cells with remarkable responses to spatial variables, including head-direction cells, grid cells, and place cells. I will describe dynamics in the head direction circuit across species from insects to mammals. I will do the same for mammalian grid cells, then focus on the remarkable theoretical coding properties of the non-local, periodic code of grid-cells for spatial location, a non-periodic, local quantity. Given that spatial computations unfold over time, I will review theoretical and experimental work on understanding the temporal/non-equilibrium dynamics of navigational computations. I will mention open questions throughout. Time permitting, I will end with ideas and experiments on how the grid and place cell circuits might support abstract cognitive computations besides spatial navigation.
Refreshments at 3:30pm in 4-349 (Pappalardo Community Room)
View the entire physics colloquia schedule at http://web.mit.edu/physics/events/colloquia.html
Host – Mehran Kardar