NEW CONDITIONED-STIMULUS TRACE CIRCUIT FOR THE RABBITS NICTITATING-MEMBRANE RESPONSE

Classical conditioning is most effective when conditioned stimulus (CS) onset precedes unconditioned stimulus ( US) onset during training, and often produces a conditioned response (CR) with a mean topography that peaks when the US is expected, even if the CS terminates before US onset. It is commonly proposed that the CS activates some form of internal stimulus trace that subsequently becomes associated with the US and generates the CR. A new CS trace circuit (CSTC) suitable for this role is presented, and computer simulation results of its operation are compared with empirical results. The CSTC responds appropriately to changes in CS amplitude and duration and more favorably models the mean topography of the rabbit's nictitating membrane response than previous computational trace models.