Publication of "The Extended Mind" (1998) - Andy Clark and David Chalmers proposed the revolutionary theory that cognition extends beyond the brain into the environment, influencing both cognitive science and philosophy of mind.
Discovery of Grid Cells (2005) - May-Britt and Edvard Moser identified grid cells in the entorhinal cortex that create a coordinate system in the brain, complementing place cells in the brain's navigation system.