Active avoidance behavior using pontine nucleus stimulation as a conditioned stimulus in the rat.

Five groups of rats were trained in an active avoidance task in a shuttle box with different conditioned stimuli. Animals with either a light-conditioned stimulus or with electrical stimulation of the ventral pontine nucleus as a conditioned stimulus rapidly learned to avoid an aversive event, while those with no conditioned stimulus, with electrical stimulation of the lateral pontine nucleus or the medial lemniscus did not learn to avoid. Therefore, stimulation of a specific subdivision of the pontine nucleus is as effective as a light-conditioned stimulus to learn an active avoidance task.