Magnetic field polarity fails to influence the directional signal carried by the head direction cell network and the behavior of rats in a task requiring magnetic field orientation.

Many different species of animals including mole rats, pigeons, and sea turtles are thought to use the magnetic field of the earth for navigational guidance. While laboratory rats are commonly used for navigational research, and brain networks have been described in these animals that presumably mediate accurate spatial navigation, little has been done to determine the role of the geomagnetic field in these brain networks and in the navigational behavior of these animals. In Experiment 1, anterior thalamic head direction (HD) cells were recorded in female Long-Evans rats while they foraged in an environment subjected to an experimentally generated magnetic field of earth-strength intensity, the polarity of which could be shifted from one session to another.