Classical nictitating membrane conditioning in the rabbit (Oryctolagus cuniculus) as a function of unconditioned stimulus locus

Examined the effects of different placements of electrodes used to present a shock UCS on conditioning the rabbit nictitating membrane response (NMR) in 2 experiments with 32 New Zealand and 24 albino rabbits. Ss were conditioned with shock leads attached either circumorbitally, at the ear base, or at the ear tip. In 1 circumorbital shock group, nictitating membranes of both shocked and unshocked eyes were monitored. Circumorbital, ear base, and ear-tip shock yielded best to poorest performances, respectively, and the shocked membrane yielded better performance than the unshocked one. Analysis of UCR and CR latencies and peak amplitude, as well as slow motion films of responses, suggests that poorer performance resulted from the elicitation of other responses, of which the NMR may have been a secondary or indirect component.