The light-dark paradigm is a widely used quick and easy test on unconditioned anxiety in rodents that does not require prior training. It is based on a conflict between the innate aversion to a brightly lit area and the spontaneous exploratory drive in response to a novel environment. If given a choice between a brightly lit and a dark compartment, rodents spontaneously prefer the dark. Anxiolytic compounds increase the time spent in the bright compartment – anxiogenic compounds work the opposite way.
The Light-Dark module in the Multi Conditioning System “2-compartment paradigms” software package requires a special 2-compartment Light-Dark arena that features an automated door and is therefore also suited for Passive Avoidance tests. Since the experiment is performed in a strictly controlled environment no external influences can interfere with animal behavior thus increasing the validity of acquired data. Change the light level of the bright compartment up to 1000 Lux to adapt the test to strain requirements.
In addition to the standard data – latency to enter the dark side and time of stay and visits in both compartments – many more behavioral measures are provided as compared to standard systems that rely on simple transfer detection only. This is especially important in evaluating the baseline behavior of the control group in drug-testing assays.
The Light-Dark test can also be performed using the MCS Open Field/Activity software package. Here a special arena without an automated door and with a dark compartment covering 33% of the test area is available.