Anterior cingulate cortex
It appears to play a role in a wide variety of autonomic functions, such as regulating blood pressure and heart rate.
Cognitive dissonance
The results of the neural scan experiment support the original theory of Cognitive Dissonance proposed by Festinger in 1957; and also support the psychological conflict theory, whereby the anterior cingulate functions, in counter-attitudinal response, to activate the dorsal anterior cingulate cortex and the anterior insular cortex; the degree of activation of said regions of the brain is predicted by the degree of change in the psychological attitude of the person.
As an application of the free-choice paradigm, the study "How Choice Reveals and Shapes Expected Hedonic Outcome" (2009) indicates that after making a choice, neural activity in the striatum changes to reflect the person's new evaluation of the choice-object; neural activity increased if the object was chosen, neural activity decreased if the object was rejected. Moreover, studies such as "The Neural Basis of Rationalization: Cognitive Dissonance Reduction During Decision-making" (2010) and "How Choice Modifies Preference: Neural Correlates of Choice Justification" (2011) confirm the neural bases of the psychology of cognitive dissonance.