Kelman (1953) thought that the greater the reward, the more likely the person is to say he likes the activity, for which he was rewarded. In fact, the opposite was found.

The hypothesis is stated in quasi-mathematical terms. Simply, dissonance occurs when you go against what you truly believe. Consonance is when you can rationalise your actions. Your action needs to be consistent with your beliefs. If you have been paid a lot of money to say something you personally do not agree with, then you can rationalise that it is OK to say these things because you have been paid to say them. If, on the other hand, you have not been paid very much, then you would need to convince yourself that you truly believe in what you are saying. Failure to do this would result in cognitive dissonance. This is when you feel uneasy with yourself over your actions. This is a situation that needs to be resolved.


71 male students from Stanford University were used. All took part as part of the course requirement. They were studying introductory psychology. In the first week of the course, they were told that they would be required to take part in experiments. Also, they would be interviewed afterwards. This was in order to evaluate the experiments. Students were urged to be honest.

When each subject was tested, they were told that the experiment was about `Measures of Performance'. They were told it would take about an hour. They were told that they would be interviewed about the experiment afterwards. The experiment was a monotonous task, involving using one hand to put spools on a tray, and turning them a quarter turn clockwise. The idea was to make the experiment as boring as possible, so that no one in their right mind would say that it was fun.

At the end of the tasks, the experimenter gave a false debriefing about the experiment. The subject was told that he was in a control condition, having not been told anything before hand. The experimental condition was where the subject had been told that the experiment was fun beforehand. The idea being, to see whether this affected performance.


In the control condition, subjects went straight to another room to be interviewed. In the other, experimental conditions, the subjects were either given $1 or $20 to persuade the next `subject' that the tasks were enjoyable. The experimenter explained that the student that usually does this couldn't make it. The next `subject' was to be a girl. Remember the true subject, thought she was in condition B of the performance experiment. The conversation between the subject and the girl was recorded on a hidden tape recorder.

The girl said nothing, until she heard a positive remark. Then, the girl said that she was surprised because a friend had told her that the experiment was boring. The conversation was for two minutes. On the way to the post-experimental interview, the experimenter said that he hoped the subject had enjoyed the experiment, and that most subjects have said that they had.

The post-experimental interview involved rating their responses using an 11 point scale. The subjects were encouraged to talk about their responses as well. The questions were:

  1. Were the tasks interesting and enjoyable? In what way were they interesting and enjoyable? The scale used ranged from -5 to +5.
  2. Did the experiment give you an opportunity to learn about your own ability to perform the tasks? The scale went from 0 to 10.
  3. Was the experiment measuring anything important? The scale went from 0 to 10.
  4. Would you have any desire to participate in another similar experiment? The scale went from -5 to +5.

The subject was asked whether he was suspicious of anything. 11 of the 71 were discarded for reasons, as stated on p147. Table 9.1 gives the average ratings of subjects. It was predicted that the $1 group would be more positive towards the experiment than either of the other two groups. For three of the questions, this is the case. the $1 group did not feel that they had learnt as much as either of the other two groups.



This is the main question. Remember that cognitive dissonance was created specifically over this point; the subjects had been asked to lie about how enjoyable the tasks were, in return for a small reward. The difference between the $1 and control groups was significant (t=2.48, p<0.02, 2 tailed). The difference between the $1 and $20 groups was also significant (t=2.22, p<0.03). The difference between the control and the $20 groups was not significant. this suggests that the small reward ($1) group have persuaded themselves that the task was enjoyable. this is what dissonance reduction theory would predict.


None of the differences reach an acceptable level of significance (i.e. p< or = 0.05).


None of the differences reach an acceptable level of significance.


There are only negligible differences between the groups. This suggests that pretending to themselves that they could learn from the experiment, would not have reduced dissonance.


It might have been said that the self convincing effect of mental rehearsal might explain the results better. If this was the case, then surely, the $20 condition subjects would have worked harder at trying to convince the girl about how enjoyable the tasks were, and by doing so, they should have convinced themselves that the experiment was fun. In fact, there is no significant difference between the $1 and $20 groups. It will be remembered that the $1 group found the task more enjoyable than the $20 group. If the self-convincing theory was operating here, then the $20 group should have worked harder and thus convinced themselves about how enjoyable the tasks were. Neither of these things happened. The alternative theory can be ruled out.


  1. If somebody does something that conflicts with his private opinion, then he will tend to change his opinion.
  2. If a lot of pressure has been brought to bear, then the person can rationalise that his action was due to the pressure. There would be no need to change one's opinion.



The theory of cognitive dissonance assumes that we like to be in a state of cognitive consistency. It is difficult to handle cognitive data if the data conflicts. This leads to a feeling of 'psychological discomfort or tension'. This is a theory of motivation, with dissonance being a negative drive state (like a punishment). People are therefore driven to reduce this state. the theory has been previously tested. It was found that if a subject makes a choice between two equally attractive alternatives, the rejected choice is subsequently viewed negatively. If subjects are put through a stressful or embarrassing situation, only to find that it was a trivial situation, the situation is subsequently seen to be more important.


Please refer to Gross Key Studies.
  1. The results are counterintuitive.
  2. The title mentions 'forced compliance'. Although this is not literally true, psychologically it is. It was difficult for the subjects to refuse the request of an authority figure.
  3. Carlsmith et al (1966) found that if the subject has to lie publicly (achieved by the subject being video taped), then more dissonance is aroused.
  4. Cooper and Fazio (1984) believed that the essential ingredient of dissonance was personal responsibility for negative outcomes, with cognitive inconsistency having little to do with it.
  5. Bem (1972) argues against cognitive dissonance by proposing his alternative theory; Self-Perception theory. We look at our actions in order to understand our beliefs. Outside observers were able to predict the subjects' responses; but, you know this would be a dispositional attribution (see Nisbett). The observer can not have access to personal information about how enjoyable a task is. Also remember subjects would be more likely to give a situational reason for their actions. This, they did not do. The observers are giving the right answers for the wrong reasons.
  6. Bem's theory is supported by the overjustification effect. This is when you receive an extrinsic reward for something that you enjoy doing anyway (already receive an intrinsic reward). We observe our behaviour, and therefore assume that we are performing the action partly for the reward. the corollary of this is that we do not hold the activity in such high regard. This is what Bem's theory predicts, and this is what usually happens.
  7. Tedeschi et al (1971) believed that a private attitude change did not occur; Instead, subjects were trying to cover up the social embarrassment of appearing insincere. This can not be the case. The $20 group did not hide their insincerity. Also, the responses were given to another experimenter, who had no knowledge of the subject's condition; so, where was the motivation to avoid social embarrassment?
  8. There exists a circular argument. Cognitive dissonance exists because the subject's rate the task as enjoyable. Subject's rated the task as more enjoyable. Because the subjects rated the task as more enjoyable cognitive dissonance exists. Zanna & Cooper (1974) gave subjects a placebo pill, that had a 'relaxing' effect. Subjects in the 'high-choice' (experiencing 'cognitive dissonance') condition, still felt tense, even though they had taken the pill. This is independent evidence to support dissonance theory.
  9. Consider what would have happened if subjects were asked to tell the truth (i.e. how boring the tasks were)?
  10. Consider what would have happened if the subjects had to lie to a male. What about the effect of the subject feeling attracted to the female?
  11. Ethics. Deceit and asking the subject to lie.
  12. This is a note about how theories are refined.

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