On rodents, the sight of a predator may induce 2 types of behavioral responses: freezing and/or flight. The looming has been developed to mimic different threatening situations for animals and thus to study these responses.
Photo credit: “Vision Guides Selection of Freeze or Flight Defense Strategies in Mice” (Current biology)
The looming includes:
- An experimental chamber, dimensions: L 480 x l 300 x h 200 mm,
- A screen located above the cage that projected the “predator”,
- One or more refuges that can be positioned in the middle or on sides of the cage
- A computer with POLY_LOOMING software to manage the experiment and POLY_Files to extract the results,
- An electronic interface,
- A floor with infrared backlight.
A control camera and our POLYTRACK software can be combined with our videotracking system to analyze freezing and flight behaviors.
It is also possible to record electrophysiological activities of neurons in rodents by connecting one the animal to our 64-channel electric commutator. In this way, this system can synchronize neuronal and behavioral events; and also sequences of appearance of the predator.
Our POLY_LOOMING software allows to:
- Set the predator appearance up on the screen: shape, type of appearance (loom or sweep), start and end point, speed…
- Save freezing sequences
Our POLY_Files software calculates:
- Number of freezing area by area,
- Freezing duration,
- Flight speed,
- Delay of response…
All the results are displayed in a Microsoft Excel compatible datasheet.