Evolution of evoked potentials during conditioning in immobilized cats

To establish the relevancy of motor feedback in the evolution of evoked potentials during conditioning, recordings were made from the Caudate Nucleus (CN), the Lateral Geniculate Body (LGB), the Mesencephalic Reticular Formation (MRF), the Occipital Cortex (OC) and the Cerebellar Cortex (Cer. C) in immobilized and non-immobilized cats before and during classical conditioning. As a result of the conditioning we observed an enhancement of the average evoked potentials (AEP) recorded in CN and in LGB in those animals able to perform the conditioned response. In contrast, the AEP recorded in CN diminished in the immobilized animals, and no changes were observed in the recordings made from the other structures, except for the appearance of polyphasic components of small amplitude and high frequency (200 Hz) in the average evoked potentials' 2nd peak, recorded from LGB. From these results we conclude that the motor feedback produced by the execution of the response is important to establish the AEP changes observed in the CN.