Is it time to lay the sleeper effect to rest?

Abstract

The "sleeper effect" has been defined as a delayed increase in the persuasive impact of a communication from a source low in credibility. This effect failed to appear in the present series of seven replications (total N = 656) of a sleeper effect experiment. However, the effectiveness of communications attributed to a source high in credibility did significantly decrease with passage of time when subjects were unprepared to counterargue with the communication. On the basis of these results and a retrospective review of related studies, it was concluded that the latter effect, by itself, could account satisfactorily for previous findings that source credibility effects dissipate or disappear with passage of time.As many undergraduate psychology students have by now learned, the "sleeper effect" is an established phenomenon in the attitude change literature. This effect is said to occur when a communication from a source of low credibility has a greater persuasive impact after some time delay than on original exposure. The communication works, that is, while the audience "sleeps" on it. Descriptions of the sleeper effect may be found in a variety of social psychology texts. Examination of the authors' bookshelves indicated that approximately 75% of recent survey texts make explicit reference to the sleeper effect as an established phenomenon.The negative results of seven replications of a sleeper effect experiment to be reported here p r o m~t e d the authors to reexamine the empirical literature on this phenomenon. Remarkably, this retrospective review led to the conclusion that the sleeper effect has never had a truly satisfactory emnirical basis. The origin21 report of a sleeper effect by Hovland, Lumsdaine, and Sheffield (1949) was based on only a subset of the opinion items they 'This research was supported in part by Grants GS-1601 and GS-3050 from the National Science Foundation and by Grant 1-R01-MH23527-01 from the United States Public Health Service. The authors are grateful to Thomas D. Cook and Walter Weiss for critically reading an earlier draft of this article; to David D. S. Poor for assistance in data analysis; and to James A. Chase, Merry Edison, Shiloh Glass, Peter Jay, Kurt Kahler, and Richard Pr6e for assistance in conducting the studies.2 Requests for reprints should be sent to Anthony G. Greenwald, Department of Psychology, Ohio State University, 404C West 17th Avenue, Columbus, Ohio 43210.used: these authors did not report any criteria that could be used to sort items, a priori, into ones that would show a sleeper effect and ones that would not. I n subsequent reports of a sleeper effect, a statistically significant increase in opinion for a group receiving a communication from a low-credibility source has never been r e p~r t e d !~ Typically, statistical significance has been achieved in sleeper effect studies bv contrasting the nonsignificant (or absent) delayed i m~a c t of a communication from a low-credibility source with a substantial decrease in impact over time in a group receiving ...

In search of reliable persuasion effects: III. The sleeper effect is dead: Long live the sleeper effect.

“…Although, the dissociation hypothesis could be modified to explain these factors, it nonetheless appears to have abdicated its sleeper effect claims, and the "old" sleeper effect-the one that has been sought in experiments that merely presented a discounting cue before an otherwise effective message-remains dormant and moribund (cf. Gillig & Greenwald, 1974). However, a new differential decay interpretation, one that serves as a more powerful summary of the empirical results, has appeared as heir to the sleeper effect throne.…”

“…A series of experiments conducted by Gillig and Greenwald (1974) is representative of many past sleeper effect studies. In their seven separate tests of the sleeper effect, which involved 656 subjects, Gillig and Greenwald found evidence for the relative sleeper effect but not for the sleeper effect proper.…”

TheOprahEffect: How Soft News Helps Inattentive Citizens Vote Consistently

“…The effects of variations in hard news consumption are virtually unchanged from Model 2. Some research-the so-called "sleeper effect" literature (see Gillig and Greenwald 1974)-suggests that individuals forget their own assessments of source unreliability (i.e., discounting cues) more quickly than the actual content of media messages (or at least disassociate the former from the latter). If so, media effects would increase over time, net of the erosion of the discounting cue.…”

The Sleeper Effect in Persuasion: A Meta-Analytic Review.

“…Such a presumption would be correct, at least in part. For instance, Capon and Hulbert (1973) qualitatively reviewed the literature on the sleeper effect available at the time and concluded that the effect was so unreliable that researchers would be better off accepting the null hypothesis than continuing to further examine the phenomenon (for similar conclusions, see Gillig & Greenwald, 1974). Other reviewers, however, have cautioned against accepting the null hypothesis and have suggested that a careful review of past data, as well as rigorous theorizing testing would resolve the controversy Eagly & Chaiken, 1993;Gruder et al, 1978).…”