The Electrophysiology of Cognitive Dissonance-elicited Attitude Change

Despite the influence that cognitive dissonance theory has had in psychology over the last sixty years, its neural correlates have only recently been investigated. The current study used electroencephalography (EEG) to explore cognitive dissonance-elicited attitude change in a free-choice paradigm. Event-related potentials (ERPs) time-locked to stimulus onset found greater voltage negativity over centro-parietal scalp during re-evaluation of dissonant choice items relative to consonant choice items, and greater negativity over left lateral anterior scalp during trials containing dissonance-reducing attitude change relative to trials without. Left lateral anterior scalp voltage amplitude was found to be negatively correlated with the magnitude of resulting attitude change. A time-frequency analysis revealed effects for high and low alpha and theta frequencies. These finding are consistent with a model of cognitive dissonance in which cortical projections of ventral striatal activity reflect reward signal changes, and where left prefrontal cortex is recruited for cognitive control and emotional down-regulation.