Holding two contradictory ideas simultaneously is disconcerting. Laying uncomfortably in a MRI machine while being told to respond to sentences as through you were enjoying the experience — "I feel calm, peaceful in the scanner" YES, for example. Leon Festinger found that people change their attitudes to make such conflicts disappear. Unlike people that also make false sentences but get paid a dollar for false agreements, they report afterwards that they enjoyed the 'scanner experience'.
The scanner allows us to piece together what happens. The more part of the dorsal anterior cingulate cortex—an area long suspected to be involved in detecting and processing conflict—lights up, the more people shift attitudes to resolve their cognitive dissonance. Likewise for part of the anterior insula. This activation is a little trickier to explain. Perhaps it is related to the conflict involving the bodily experience of being in the scanner. The picture shows the activations on an inflated cortical surface.
As with every research, there are reservations. The task set up involved a social element that might have effected it.
They were then told that a patient had been scheduled to be scanned after them and was to perform a similar task in the scanner. This patient, the participants were told, was now in the scanner control room, watching the screen of the experimental control computer, and was very nervous and uncomfortable about the upcoming scanning session. The participants were then told that several of the sentences were about their attitudes toward the scanner and the task and were asked if they would be willing to respond as though they were enjoying being in the scanner and performing the task, regardless of how they actually felt about the experience. This, they were told, might put the patient’s mind at ease, as the patient in the control room could see the responses on screen.
Perhaps there was an empathy factor to the condition in which cognitive dissonance was induced (the person got a dollar instead, rather than this story). The researchers try and argue this was not a factor but one wonders why they did not give a dollar or some, for a variant of this story.
van Veen V, Krug MK, Schooler JW, Carter CS. (2009).
Nat Neurosci. 12: 1469 – 1474 doi:10.1038/nn.2413