A telemeter for monitoring the electrocardiograms of freely moving mice.

Abstract Telemetry was used to monitor the electrocardiogram (ECG) of a freely moving mouse in three behavioral situations—shock avoidance runway, open field, and home cage. A small, inexpensive, easily fabricated telemeter was used to monitor the ECG. The circuit and characteristics of the telemeter are described as well as the harness, electrode placement, receiver and antennae. Experimental records are presented showing that the only period when the ECG was unreadable was during shock in the shock avoidance runway.