[Sturctural outline of spontaneous motor activity monitor using infrared photoelectric switch for small animals (author's transl)].

A simple monitor was developed for measuring the spontaneous motor activity (SMA) of small laboratory animals. The monitor was designed to measure animal ambulation along a horizontal axis by means of two infrared photo-beams. Using the monitor, male mice 7 to weeks of age at the commencement of this experiemtn showed high SMA values for the first 15 min and low values for the last 15 min of the experiment.