Development of the Hippocampal Cognitive Map in Preweanling Rats

The Space in Your Head Space, and events associated with places and spaces, are represented in the brain by a circuitry made of place cells, head direction cells, grid cells, and border cells. These cell types form a collective dynamic representation of our position as we move through the environment. How this representation is formed has remained a mystery. Is it acquired, or are we born with the ability to represent external space (see the Perspective by Palmer and Lynch )? Langston et al. (p. 1576 ) and Wills et al. (p. 1573 ) investigated the early development of spatial activity in the hippocampal formation and the entorhinal cortex of rat pups when they first began to explore their environment. Rudiments…