ABSTRACTThe present study demonstrates that the orienting response (OR) to the conditional stimulus can be conditioned with a delayed differential conditioning paradigm. Controls utilized were two “sensitization” and one backward‐trace differential conditioning group. Conditioned ORs, conditioned anticipatory responses, and conditioned responses at latency of unconditioned response in the absence of the unconditioned stimulus were all demonstrated. In the backward conditioning group the amplitude of the OR to the tone preceded by shock was lower than that found for any other group. Refractoriness of the peripheral components of the electrodermal response (EDR) are invoked to account for this fi