Climbing fiber lesions disrupt conditioning of the nictitating membrane response in the rabbit

The pattern of acquisition of the classically conditioned nictitating membrane response was determined in rabbits which had recovered from a surgical lesion of the olivary decussation. In comparison with sham-operated controls, the animals with climbing fiber lesions showed delayed and incomplete conditioning. This observation supports the hypothesis of Marr and Albus that motor learning occurs in the cerebellar cortex when conjunctive inputs arrive along both the mossy and climbing fiber pathways.