Sleeping effect

Usually, when people are influenced by a persuasive message (for example, they see ads that they like), their attitude to the content of the message changes immediately: the credibility of the received message grows. However, after some time, the attitude to the topic covered in the message will become closer to the original: as if people had never heard this message or advertisement. This means that the new entity that was formed under the influence of a persuasive message will be replaced by another entity that is closer to the original entity. It is such a pattern that occurred most frequently in longitudinal studies devoted to the study of persuasive communication . ^[one]

And vice versa: when a message is accompanied by a depreciating stimulus (for example, a counterargument, or it comes from a source that is not credible), there will not be an initial change in the attachment to the message subject. Most likely, this situation will cause suspicion of the message recipient of the implausibility of the information. However, after some time, the level of trust in the received message will still grow. This is called the " sleeping effect ." ^{[2] [3]}

For example, during a political campaign for the upcoming elections, an undecided voter sees negative information about one of the parties. At the end of the message is a mention that the text was ordered by the opposition party . Most likely, this will make the voter doubt the veracity of the message, and his opinion about the party mentioned in the text will not worsen after reading the ordered anti-advertisement. However, even though the source of the message is not trustworthy, the voter is likely to believe in the information received after a while and will vote against the party mentioned in the revealing anti-advertising.

Such a phenomenon of changing attitudes has puzzled social psychologists for half a century, firstly, because of its illogicality, and, secondly, because of its potential importance for understanding the processes of formation and change of attitudes. ^[1] The phenomenon of the “Sleeping Effect” has been widely studied in studies of persuasive communication. Despite the rather long study period, the “sleeping effect” proved to be very difficult to detect or repeat, with the exception of a few studies. ^[four]

For the first time, the “sleeping effect” was discovered among soldiers of World War II as a result of attempts to change their beliefs and moral principles regarding the war. Hovland , Lamsdane and Sheffield showed soldiers a film on army propaganda (“ Why We Fight ” - “Fighting Britain” cycle), and then measured the soldiers ’opinions 5 days and 9 weeks after watching. It turned out that after 5 days there were practically no differences in beliefs between those who watched (experimental group) and those who did not watch the film (control group), i.e. There was no result from propaganda. However, during the measurement, 9 weeks after watching the film, the beliefs of the soldiers who watched the film changed: they began to feel better about the war. This delayed effect of the influence of beliefs in the experimental group, Howland and his colleagues called the "sleeping effect." ^[2]

The name "sleeping effect," given by Karl Hovland , dates back to the field of espionage . ^[5] So, a sleeping agent , or a sleeping spy, is usually called an agent sent to an enemy camp and “lying” there “to the bottom”. ^[6] He lives an ordinary life, his task is to gradually establish contacts, rooting in the enemy’s system. He does not take any immediate action, but activates when his help is needed.

The first attempts to confirm the “sleeping effect” were developed in accordance with the existing understanding of the process of persuasion. Hovland and his colleagues presented a research program aimed at examining the relationship of the message source and the attituation to information as components of the “sleeping effect”. They suggested that over time, people forget about the unreliable source of the message, and the initial distrust of the information decreases. ^{[7] [2]}

Then, the authors somewhat changed their minds and suggested that the recipients of the information do not completely forget about the source of the information: rather, over time, the association between the devaluing stimulus and the information weakens, and due to this, the “sleeping effect” is observed. ^[2]

The difference between these two assumptions is that when forgotten, the devaluing stimulus disappears from memory altogether, and when dissociated, these two components - the message and the devaluing stimulus - remain in memory, but become more independent from each other.

Howland and Weiss conducted a study to test their dissociation hypothesis. Researchers studied attitudes toward nuclear submarines and antihistamines. At the same time, authoritative persons - scientists, and in the second case - unauthorized newspapers (devaluing incentive) turned out to be conditional sources of information. In the direct measurement of the attitudes immediately after receiving information, trust was greater in the information received from the scientist. However, after 4 weeks, according to the results of the delayed measurement, confidence in the information received from an authoritative person decreased, and trust in information received from a low-authority person (depreciating incentive) increased. Moreover, if we recall the source of the information (scientist or newspaper), the subjects' attitude to the information and trust in it will return to the level of initial, direct measurement: the information received from the scientist will again be trusted more, and the information received from the newspaper - less. ^[2]

There is something important that Howland and his colleagues did not take into account: why, over time, the devaluing stimulus becomes less accessible than information, if initially both of these parts were equally significant. To answer this question, Greenwald, Pratkanis et al. ^{[8] [9]} conducted a study to identify the conditions under which the “sleeping effect” will or will not occur. Pratkanis conducted a series of 17 experiments in which he placed a depreciating stimulus either before or after the message, and found that the “sleeping effect” occurred mainly in those cases when the depreciating stimulus followed the message, and not when it came in front of it. In order to explain their discovery, Pratkanis et al proposed a slightly modified hypothesis of forgetting: they suggested that the “sleeping effect” arises from the fact that the influence of the message and the effect of the devaluing stimulus are destroyed at different rates. At the heart of this is the assumption that communication and a depreciating stimulus act as two connections working in opposite directions. The “sleeping effect” occurs when the effect of both parts is initially approximately the same, but the effect of the devaluing stimulus decays faster. At the same time, the timing of the presentation of the depreciating stimulus is important, since the message presented first may remain in memory longer, while more recent information interferes faster. Thus, the “sleeping effect” should occur in cases where a depreciating stimulus is presented at the end of the act of persuasive communication, thereby stimulating the influence of the information content of the message.

Thus, Pratkanis, Greenwald, Leppe and Baumgardner ^[9] proposed an alternative hypothesis, which differed from the hypothesis of Howland and his colleagues ^[2] . This hypothesis emphasized the importance of the conditions for the emergence of the “sleeping effect”, which were not mentioned in the dissociation hypothesis. In addition, the requirements for the occurrence of the “sleeping effect” proposed by Gruder et al. ^[10] did not detail the empirical conditions necessary for the manifestation of this effect.

One of the main reasons for doubts about the existence of the "sleeping effect" is the difficulty of reproducing this effect in the course of scientific research. For example, in 7 studies by Gilling and Greenwald in 1974, the “sleeping effect” was not detected. Researchers measured over 600 subjects who received reports on various topics (for example, the benefits of penicillin, vitamin C, and medical examinations). Messages were attributed to a source of low confidence: the traditional healer. However, there was no delayed increase in the impact of the message. ^[eleven]

However, Cook et al suggested that in previous studies the “sleeping effect” was not detected for reasons not meeting all the necessary requirements. In particular, they argued that the “sleeping effect” would only occur when:

1. The message is convincing;
2. The depreciating stimulus is strong enough to prevent an initial change in attribute;
3. A sufficient amount of time has passed between the direct measurement of the attribute and the delayed measurement;
4. The message itself is strong enough to act on the appraisal during delayed metering.

Moreover, all 4 conditions must be satisfied simultaneously. ^[12]

In the studies of Gruder and colleagues, the following conditions for the occurrence of the “sleeping effect” were noted: a) the recipients of the message were encouraged to pay attention to the content of the message with a request to note the most important arguments in it; b) the devaluing stimulus was presented after the message; and c) the recipients evaluated the degree of trust in the message source immediately after receiving the message and the devaluing stimulus. ^[13]

Thus, in a study by Gruder and co-authors, subjects were provided with a text with the shortcomings of a 4-day work week. During the reading, respondents had to highlight the most important arguments; after reading the text, a counterargument was given, and immediately after that the degree of trust in the source was assessed. The results were such that the effect of a persuasive message increased with a delayed measurement after 6 weeks, compared with a direct evaluation: the subjects showed a more negative attitude to the introduction of a 4-day week. ^[14]

The ability to comply with all of the above conditions is unlikely. However, the above facts confirming the manifestation of the "sleeping effect" exist. This suggests that the onset of the “sleeping effect” may simply be based on other conditions and methods.