If we were told that sometimes we think we are more of a political speech or a propaganda ad after a few months of seeing it than not at the very moment we receive it, we would surely say that is just impossible.
However, in social and experimental psychology, the existence of the sleep effect was raised, A strange phenomenon that occurs when, after a few weeks, our attitudes towards a persuasive message change significantly.
This phenomenon is extremely rare and it has even been suggested that it is not something that actually happens, but it has received several explanations and attempts have been made to remedy it experimentally. Let’s take a closer look at what it is.
Sleep effect: what is it?
The effect of sleep is a curious phenomenon, proposed by social and experimental psychology, which maintains that sometimes a message that was meant to be persuasive from the start, instead of being assimilated immediately, will receive more force when a certain time has passed.
Usually when you say or show something that carries a message, be it political, opinionated, ethical or of any kind, it is usual for the person to express a series of immediate attitudes towards it. of the content of the message itself. Depending on the credibility of what is said in the message, the person has essentially made one of two decisions: to accept what they are telling you or to simply not accept it.
Whether or not you think the information you just received is true, it is normal that after a while you will forget the content of the message. In other words, if a person is exposed to a message of any kind, it is normal that they made a greater impression immediately after receiving it than not a few weeks.
However, and depending on the definition of the effect of sleep, what sometimes happens is that the message, which was not originally taken for granted, is taken into account after weeks. Not only does the person still remember what they were told a long time ago, but they also show a whole series of favorable attitudes or agree with what they were told at the beginning.
This phenomenon, as described here, may seem counterintuitive. If you doubt the content of a message from the start, especially because you doubt the veracity of the source of the information, it is normal that over time it will end up being forgotten or become even more critical by compared to what was said in it.
The origins of the definition of this particular phenomenon can be found at the time of World War II. The United States clearly had an interest in keeping morale high and convincing its troops of the need to help its allied countries, including Britain. To this end, the war department of this country used propaganda entertainment, especially films, in which it was intended to convey a message of optimism and sympathy towards the Allies.
However, despite the large investment of the United States in the making of these films does not seem to have produced the expected effects. That is why, through a series of experiments, it was proposed to see how the message spread among the troops. Thanks to these experiences, we saw that the message they intended to spread was not as well received as they thought.
We have seen that these short films which were informative in nature and sought to reinforce certain existing attitudes related to the war seemed to have a very moderate impact in the short term. However, after a few weeks it was seen that among the troops there was a marked increase in this optimism and support both to their nation and to allied countries.
Theories behind this phenomenon of persuasion
As we were discussing, the effect of sleep is striking because it is a rather counterintuitive phenomenon. The normal thing would be that when faced with a post that we doubt, its content is viewed even more critically over time.Don’t end up seeing it as a real thing after a few weeks.
Several aspects have been proposed in an attempt to explain why and how the effect of sleep occurs, although to this day there is still controversy in this regard and it seems that, experimentally, it is difficult to reproduce.
1. Forget it’s doubtful
The first to describe this phenomenon were Hovland, Lumsdaine and Sheffield in 1949. These researchers, taking the case of American soldiers, hypothesize that, some time after receiving the message, forgets that it has questionable aspects and remains the content. of the message itself. .
In other words, over time, the attitudes initially expressed are forgotten, which makes the content of the message itself more important, Generate new attitudes.
This, however, is not that simple. It is quite simplistic that people, after a while, change their attitude just because they forget where a particular message came from or they will believe what has been suddenly said.
The other proposition of the same research group is that in reality the origin of the message is not forgotten, what happens is that it dissociates with the message. In other words, it is known to have had a dubious origin, but it is not known which one.
Faced with this fact, the person gives him more importance, and even gives him another opportunity to “see” it more objectively, which can affect his attitudes if the original persuasive objective of the “message is satisfied.”
2. Different content and treatment of the source
Years after Hovland’s group proposed what we saw in the previous point, Pratkanis, Greenwald, Leipe and Baumgardner’s group came up with an alternative hypothesis to the pre-1988 explanation.
This research group proposed that the effect was given because people encode the content of the message differently from the source it came from.
In other words, we know how to objectively differentiate what the message implies versus who is the source.
By treating content and source differently, the origin is the forgetfulness or loss of strength over time, while the content or the message itself remains.
By contemplating content separate from its origin, it is more likely to be seen as something true.
How is it given?
Anyway, the mechanism that can give a more objective explanation to this strange phenomenon, so that the message is retained over time, must meet the following two conditions:
1. Strong initial impact
The effect of sleep cannot occur if the message that was sent at the beginning has a strong and remarkable persuasive impact.
Although the person won’t believe it, the fact that this message is strong keeps it in their long-term memory.
2. Message rejected a posteriori
When a message comes from an information source that is not considered reliable, that message tends to be discredited from the start.
However, if it is discovered that the source of the information is unreliable, but after the message has been issued, the message will be better remembered, run the risk of being more suggestible in the long term.
For example, we attend a political meeting on television, and at the end of the candidate’s speech, a presenter comes out pointing out, with evidence, all the election promises broken by the same candidate when he won a past election.
While we have had proof that this politician is untrustworthy, just seeing the evidence after hearing the speech does not take away from the fact that we remember what he said when exposing this. what he would do if he won this election.
After a few months, we are more likely to remember the content of the speech than the evidence that has been given after it’s over.
Criticisms of this phenomenon
The main controversy to which this phenomenon has been exposed is the way in which it is product. It is very difficult to foresee the possibility that a message that has just been released and that the public did not believe it or question it a lot, over time will end up being taken into account and even drastically change the attitudes of those who received it at the beginning.
It was practically impossible to reproduce this phenomenon under laboratory conditions.. The theories raised by the Hovland and Pratkanis groups stand out for their clarity on what they mean by persuasive message and unreliable source. Experimental psychology strongly doubts that this phenomenon is plausible in real life beyond its hypothetical approach.
- Capon, N. & Hulbert, J., “The Sleeper Effect – An Awakening”, Public Opinion Quarterly, Vol.37, No.3, (Fall 1973), pp. 333-358.
- Cook, TD, Gruder, CL, Hennigan, KM, and Flay, BR, “History of the Sleeper Effect: Some Logical Pitfalls for Accepting the Null Hypothesis,” Psychological Bulletin, Vol.86, no. 4, (July 1979), pages 662-679.
- Hovland, CI, Lumsdale, AA and Sheffield, FD, Experiments on Mass Communication: Studies in Social Psychology in Second World War: Volume III, Princeton University Press, (Princeton), 1949.
- Hovland, CI, Weiss, W., “The Influence of Source Credibility on Communication Effectiveness,” Public Opinion Quarterly, Vol.15, No.4, (Winter 1951), pp. 635-650.
- Pratkanis, AR, Greenwald, AG, Leippe, MR and Baumgardner, MH (1988). In search of reliable persuasive effects: III. The sleep effect is dead: long live the sleep effect. Journal of Personality and Social Psychology, 54 (2), 203-218. https://doi.org/10.1037/0022-35126.96.36.199