Effect of CS habituation on eyelid conditioning

Administered 3 independent groups of 10 rabbits each 500 acquisition and 200 extinction trials in the eyelid conditioning situation following either 1300, 100, or 0 exposures to the CS prior to conditioning. The Ss receiving 1300 and 100 preconditioning CS presentations were slower to start conditioning than the Ss receiving no such presentations. In addition, the Ss receiving 1300 exposures to the CS prior to conditioning required more trials to reach a high level of acquisition performance and evidenced longer latency CRs at asymptotic performance levels than the other Ss. Rapidity of extinction was directly related to the number of preconditioning CS presentations.