Abstract
Eight groups of subjects were trained to make a button-press avoidance response and were then given 15 treatment trials before being tested for extinction. Subjects in the Flooding group were exposed to the 2000-Hz tone (CS) for 20.0 sec. irrespective of their responding. In six other groups subjects were treated according to a 2 × 3 design. They were either exposed to the original CS (CS groups) or a hierarchy of tone stimuli leading to the CS (Graded CS groups). Subjects were asked either to imagine nothing (CS-only and Graded CS-only), imagine neutral events (CS-neutral and Graded CS-neutral), or imagine pleasant events (CS-pleasant and Graded CS-pleasant). A Yoked-flooding group in which CS durations were identical to the CS durations in the CS-pleasant group was also tested. Testing during extinction showed that avoidance responding was most resistant to extinction in the CS-only, Graded CS-only, and Neutral groups and least in the Flooding group. The Pleasant groups showed quicker extinction than the Neutral, CS-only, and Graded CS-only groups. The CS-pleasant group was quicker to extinguish than the Yoked-flooding group. Although flooding was the most effective procedure, the results showed that not all the effects of response competition, through imagination of pleasant experiences, could be explained through the CS-exposure hypothesis.