Incubation of anxiety: Effect on temporal generalization

Abstract

Temporal generalization gradients were obtained, either immediately after training or after a 6-hr. delay, from Ss exposed to either aversive or innocuous reaction time signals. Smaller generalization decrements were found for Ss receiving delayed testing, and signal aversiveness did not affect the magnitude of the decrement. Instead of finding support for an "anxiety-incubation" hypothesis, it was concluded that non-emotional factors associated with elapsed time produce flattened generalization gradients.For human Ss, the effect of delayed testing on the PGR has been to elevate, but not flatten, the generalization gradient, suggesting an increase, or "incubation," of conditioned anxiety across time (Mednick, 1957). However, several acquired-drive studies have indicated that, following classical aversive conditioning, rats show smaller generalization decrementS-without elevation of the overall gradient-if time elapses between conditioning and testing (McAllister & McAllister, 1963; Desiderato, Butler, & Meyer, 1966).While it is possible that the "incubation effect" may be limited to human Ss, wide procedural differences make comparison between these studies difficult. Accordingly, the present study is an additional test of the "incubation effect" at the human level, using a temporal generalization paradigm. To test whether gradient effects associated with delay necessarily involve changes in conditioned emotionality, for half the Ss, the training phase did not involve aversive stimulation. Thus, gradient effects could be attributed to an "incubation" process only in the case of Ss tested following aversive training. MethodThe Ss were 40 college women. 3 Following the procedure for obtaining temporal gradients described elsewhere (Desiderato, 1964), each S was trained for 25 trials to press a telegraph key in response to an auditory signal delivered via earphones once every 12 sec. Since the S's response immediately terminated the signal, signal duration was equivalent to her reaction time. Throughout the experiment, for half the Ss, the signal was white noise at an aversive level of 119 dB, SPL (Group N); the remaining Ss heard a pure tone of 1000 cps, at 86 dB, SPL (Group T).Following the 25th training trial, for half the Ss in each group the generalization test commenced without interruption. Ss in the remaining subgroups were asked to return for a continuation of the experiment 6 hr. later. Every S received five testblocks,eachconsisting of seven trials. Within each block, the following interstimulus intervals were used: 5.5, 7.0, 9.0, 12.0, 15.5, Psychon. Sci., 1966, Vol. 6 (4) 20.0, and 26.0 sec. The order varied randomly from S to S and from block to block. After the last test trial, Ss were asked to indicate on 5-point rating scales how unpleasant they found (1) the signal to respond (noise or tone) and (2) the entire experiment. Results and DiscussionAll RT scores were transformed into reciprocals. Analysis of training trials revealed that Group N responded faster than Group T, F=34.71, df=I/36, P < ....