The light/dark transition test (LDT) is one of the most widely used tests to measure anxiety-like behavior in mice. The test is based on the natural aversion of mice to brightly illuminated areas and on their spontaneous exploratory behavior in response to mild stressors, such as novel environment and light. This test is also sensitive to anxiolytic drugs treatment. The test apparatus consists of a box divided into a small (one third) dark chamber and a large (two thirds) brightly illuminated chamber. Mice are placed into the lit compartment and allowed to move freely between the two chambers. The first latency to enter the dark compartment and the total time spent in lit compartment are indices for bright-space anxiety in mice. Transitions are index of activity-exploration, because of habituation over time. LDT is quick and easy to use, without requiring prior training of animals. Here, we present our protocol that has been able to detect both anxiolytic-like (reduced anxiety) and anxiogenic-like (increased anxiety) behavior in mice.
Laboratory-bred mice Note: Mice housed in groups 3-5 per cage, kept in a room with controlled temperature (~23 °C) and humidity under 12 h light/dark cycle (lights on at 7:00 AM) with ad libitum access to food and water.
70% ethanol
Equipment
The apparatus for the light/dark transition test consists of a box (42 x 21 x 25 cm) divided into a small (one third) dark compartment and a large (two thirds) illuminated compartment (Crawley and Goodwin, 1980). A restricted opening 3 cm high by 4 cm wide connects the two chambers (Figure 1).
Indirect white light source
Digital lux meter
Video camera (placed directly above the apparatus)
Digital chronometers for manual analysis or computer for automated analysis
Figure 1. Light-dark transition test apparatus
Software
TSE-Systems, model: VideoMot2 (computer software for automated analysis)
Serchov, T., van Calker, D. and Biber, K. (2016). Light/Dark Transition Test to Assess Anxiety-like Behavior in Mice. Bio-protocol 6(19): e1957. DOI: 10.21769/BioProtoc.1957.