[A supernormal period in the parallel fibers of the cerebellum of the rat and mouse].

The response to a conditioning stimulus applied to a bundle of parallel fibres of the Rat or Mouse cerebellum is followed by a supernormal period during which the fibre conduction velocity increases by an average of 12% in the Rat and 6% in the Mouse. The duration of this effect is about 250 msec. in the Rat and 350 msec. in the Mouse, with maximal values at 60 and 100 msec. respectively.