1.   Another curious feature of the system is that the same place cell may be used in more than one spatial map.

2.   A place cell that fires when an animal is in one position will stop firing when the animal moves to a different place.

3.   A set of overlapping place cells forms a mental map as a pattern of strengthened synapses between the cells.

4.   Discovery of the place cells set up a debate among neuroscientists.

5.   Each place cell is activated when an animal is in a certain region in its environment, Wilson said.

6.   Hippocampal place cells that fired together when the rats explored the box showed an increased tendency to fire together during sleep, Wilson said.

7.   Humans also have place cells, Wilson said.

8.   In a series of experiments, Wilson implanted electrodes into so-called place cells in the rat hippocampus.

9.   Researchers can tell where a mouse is in its cage by noting which place cell is firing.

10.   The mouse hippocampus has about a million large, complex nerve cells known as place cells because of their role in recording spatial memories.