How does a drinking bottle or food on the cage affect the motion detection through the MOUSE-E-MOTION Universal Data Logger?

The infrared radiation emited by the animals is almost completely absorbed by a drinking bottle or food bits, preventing an accurate motion detection. To achieve extensive detection of activity it is recommended to use a small drinking bottle (50-100ml) and as less food as possible on top of a cage, or to provide the animals directly in the cage with water (e.g. through agar cubes) and food during the experiment. (Normally, a small “blind spot” in the experiment setup doesn’t make a difference and is statistically irrelevant.)