Abstract
A very simple antirotatory device permitting free movement of small and middle-sized animals is described. It allows the performance of chronic experiments in animals bearing several catheters and wires for perfusion or recording purposes. A set of eight metal plates, articulated end to end by small brackets, sets the animal's head at a fixed point on the ceiling of the cage. This device has been perfectly tolerated by rats during 2 wk to 3 mo.