How we change what others think, feel, believe and do
Do or say something (A). Then repeat it (A). Then a third time do or say something different (B).
In persuasion, use the surprise of the third element to help change minds.
I like the idea. I like the though. But I won't buy it at that price.
The managers like it The employees like it. But the shareholders are against it. So let's figure out together what we can do.
The basic principle of the AAB pattern is that by repeating two items (the two As), the very human pattern-detection system is stimulated. This leads to prediction of a continuation of the pattern with a third A. When the B appears (ie. not A), this causes surprise, which makes the person more open to persuasion. In this way AAB uses the repetition principle to set up the AA pattern and then creates confusion with the unexpected B.
You can also use pattern-change variants such as AAAB, AAAAB, etc. AAB is simply the most economic version of this pattern. Adding more As strengthens the pattern and so also increases expectation and hence the B creates even greater surprise and confusion.
Spotting patterns is essential to basic survival as it enables us to predict the future, as, by definition, patterns generally consist of items that repeat themselves more than once.
This patterning is deliberately used in music where a sequence is repeated and then changed to create a stimulating and pleasurable feeling.
It also appears in humor, where the unexpected appearance of the B is found to be funny.
Both music and humor are difficult to explain in terms of evolutionary benefit. This view of pattern interruption helps link it as an adaptation to situations other than threat assessment.
Rozin P, Rozin A, Appel B, Wachtel C. (2006). Documenting and explaining the common AAB pattern in music and humor: establishing and breaking expectations. Emotion. 6(3), 349-55.