The effect of the inter-trial interval on the acquisition, extinction, and recovery of verbal expectations.

Abstract

Verbal expectations of 3 groups of 152, 50, and 67 college students were studied under the following conditions: Group I- 24 acquisition, 24 1st extinction, and 20 2d extinction trials were given at a 5-sec. rate. A 30 min. recovery period intervened between 1st and 2d extinction. Group II-conditions were the same as for Group I except trials occurred at a 10-sec. rate and the recovery interval was 4 mins. Group III-24 acquisition and 15 extinction trials were given at a 20-sec. rate. Recovery was not tested. Within the time limits here employed spaced practice is of no advantage in either acquisition or extinction of verbal expectations and spontaneous recovery of verbal expectations occurs, but within the limits of the time intervals used, no evidence of progressive recovery is obtained. Both the progressive character of spontaneous recovery and the beneficial effects of spaced practice in conditioning expts. are apparently due to decremental rather than expectancy factors.