Rapid transfer of training occurs when direct mossy fiber stimulation is used as a conditioned stimulus for classical...

Fifteen rabbits were classically conditioned using stimulation of the right pontine nuclei as a conditioned stimulus and a corneal airpuff as an unconditioned stimulus. After conditioning criterion was reached, the stimulation conditioned stimulus was transferred to the left pontine nuclei and the rate of conditioned response acquisition observed. Our results indicate that when electrodes were placed symmetrically in the right and left pontine nuclei, extremely rapid transfer of training occurred. Together with previous data, the present data supply further indirect evidence that the site of neural plasticity which underlies acquisition and retention of classically conditioned skeletal muscle responses is located efferent to the pontine nuclei, namely in the cerebellum.