A building block-based beam-break (B 5 ) locomotor activity monitoring system and its use in circadian biology research.

Locomotor activity is one of the most commonly assayed animal behaviors. It is the gold standard for assessing behavioral circadian rhythmicity. Here, we develop a flexible and affordable locomotor activity monitoring system that does not interfere with the behavior of animals. We validate the reliability of the system in multiple circadian biology research scenarios. This device is customizable and can be used for many animal species.