Psychology 101 Understanding the Sleeper Effect With Examples

Psychology 101 Understanding the Sleeper Effect With Examples

Did You Know?

The sleeper impact turned into observed by using Carl Hovland, Arthur Lumsdaine, and Fred Sheffield in 1949, within the direction in their take a look at that examined the impact of a World War II propaganda movie on American soldiers.

During World War II, a chain of documentary films had been commissioned by way of the United States government as a way to explain to the American infantrymen the purpose behind the involvement of US forces inside the struggle. Carl Hovland and his colleagues had been curious to examine the lengthy-term effects of such propagandized messages. During the course of their observe, they discovered that the infantrymen first of all brushed off the records within the movies, because it turned into genuinely part of a propaganda, and as a result, changed into now not a very reliable supply of records. When reexamined after a massive time period, the researchers were astounded to discover that, in place of an boom within the rejection of the statistics, the squaddies showed an boom in its acceptability. This led Hovland and his colleagues to posit that, the passage of time had caused the soldiers to overlook the source of the data, and in flip result in the reputation it. This become the first documented instance of the sleeper impact.

Sleeper Effect

Normally, the persuasiveness of statistics progressively decreases over a period of time. Often, this facts is associated with cues consisting of source credibility and morality. Some of these cues are high-quality, even as some are negative. Messages followed by way of wonderful cues are commonly effortlessly familiar and believed by way of humans, even as those associated with poor cues (discounting cues) are regarded suspiciously and once in a while even dismissed.

However, it's been found in many research that in spite of the initial rejection of the message, human beings generally tend to get persuaded over time, main to an growth within the popularity of that message. This phenomenon of delayed persuasion is referred to as the sleeper effect.

However, for the sleeper effect to show up, 3 basic situations ought to be met. They are:

The message itself should be persuasive
The discounting cue should to start with suppress mindset alternate
The discounting cue need to emerge as dissociated from the message through the years

It should be mentioned that the effect is seen to disappear if the audience is reminded of the supply.

How Does It Work?

There exist 3 hypotheses that try to explain the motive behind this impact.


The sleeper effect prompted Hovland and his colleagues to agree with that attractiveness was possible due to the non-remembrance of the discounting cue. To take a look at this speculation, the researchers carried out a series of experiments which had been made up of sets of human beings each. Each set was instructed the identical message or information, however one become related to a relatively credible supply, while the other become associated with an untrustworthy supply. Following up on the two agencies confirmed that, to begin with, the message from the credible supply became easily well-known compared to the message from the unreliable supply. After a positive time frame, the subjects have been again tested. This examination discovered that there was a big boom inside the acceptability of the message related to the discounting cue. This brought about the hypothesis that the effect became found because of the reality that the topics had forgotten the unreliable nature of the supply. However, later examinations revealed that, despite the boom in acceptability, maximum of the topics still remembered the non-credible supply of the message.


Due to the drawback of the above hypothesis, the researchers proposed a brand new principle, one which claimed that the topics did not forget about the source completely, however merely possessed a weakened association with the message, or in different words, the message and discounting cue had been dissociated. Since the association of the source and message is weakened over time, so that it will be dissociated, take into account of the message could not reason the recall of the source as well, thereby inflicting a not on time reputation/persuasion, which results in the sleeper impact.

Differential Decay

Hovland and his colleagues succeeded in elaborating many sides of this effect, but they managed to ignore one issue, this is, why the discounting cue changed into easily forgotten or much less accessible, but now not the message itself. This question turned into investigated by using Greenwald, Pratkanis, and their team, in a chain of experiments designed to decide the unique parameters required for the incidence of the sleeper effect. Their experimental consequences recommend that, the message and the cue decay at distinct quotes. After publicity, the impact or reminiscence of the cue degrades or decays plenty quicker, compared to the impact of the message. Also, interestingly, the sequence of the cue and message additionally played an essential position in bringing approximately the sleeper effect. The impact become visible simplest in instances in which the cue accompanied the message and bolstered the message content material.

Real-existence Examples

➠ During political election campaigns, regularly, the applicants of the opposing birthday celebration are focused through bad feedback, advertisements, or news. This in large part impacts the not sure voters, who first of all push aside those occurrences as being slanderous tries, but later, due to the sleeper impact, keep best the reminiscence of the message however now not the source, causing them to vote in opposition to the defamed candidates.

➠ Young children of divorced parents, who display no signs and symptoms of mental pressure or trauma as a result of the divorce, often showcase difficulties regarding relationships, believe, and intimacy at some point of early adulthood.

➠ The frequent concept that autism is because of MMR vaccines is due to the sleeper impact because of an unreliable supply inside the shape of an incorrect clinical have a look at.

➠ The sleeper impact is obvious in the case of word of mouth advertising. Product reviews are frequently unfold this way. It may also both be a friend telling you about it, or a salesman. The identical can occur on web sites and forums as properly.

➠ Reading approximately facts, facts, or anecdotes from an unreliable supply might also bring about the presentation of this impact.

➠ Social media applications can act as systems for the propagation of untruths or propaganda in opposition to or in assist of an man or woman or entity.

The best powerful way to triumph over any and all results of the sleeper effect is to impeach and look into the supply of your know-how. If a certain piece of data reaches you, you should decide the steadiness of the supply, and confirm the validity of the statistics earlier than applying it in any manner.

Subscribe to receive free email updates: