Brain’s GPS cells map time and distance, not just location
When rats run on a treadmill, grid cells act like clocks and odometers
![](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2015/11/110315_ls_grid-cell-main.jpg?fit=860%2C460&ssl=1)
KEEPING TIME A grid cell fires off signals at particular times as a rat runs on a treadmill. The cell behaved similarly as the rat ran at slow (blue), moderate (brown) and fast (green) speeds.
B. Kraus et al/Neuron 2015