Operant conditioning of trigeminal nuclear evoked potentials.

The purpose of this study was to demonstrate operant conditioning of potentials in the rat's trigeminal complex evoked by stimulation of the primary descending trigeminal tract. The amplitude of the prominent component of the potential, with a peak at 10 to 22 msec after the stimulus, was conditioned. Reinforcement was electrical stimulation of the medial forebrain bundle. A bidirectional conditioning paradigm was used to control for noncontingent effects of the reinforcer. Eight of the thirteen animals demonstrated control of the evoked potential. Application of the neural conditioning paradigm to the investigation of loci of neuronal plasticity is discussed.