Cited research: Science 328, 1573–1576; 1576–1580 (2010)

How do newborn rats find their way around? Easily, it seems: two groups report that some basic elements of spatial representation don't require any experience.

Researchers recorded the activity of three types of neuron in the brains of rat pups as they explored their environment for the first time. Tom Wills, Francesca Cacucci and their colleagues at University College London report that head-direction neurons — which are tuned to fire according to the direction in which the animal points its head — are already fully developed by the time a pup first ventures from the nest. The basic properties of place cells, which respond to particular locations, are also established by then. Conversely, a third type of cell for spatial orientation, the grid cell, doesn't begin firing stably until later.

Edvard Moser and his colleagues at the Norwegian University of Science and Technology in Trondheim largely agree, but say that rudimentary grid-cell properties are also present during the pups' first explorations.

Both studies underscore that the animals may be born with spatial cognitive abilities. A.K.