Cognitive dissonance resolution depends on episodic memory

Mariam Chammat (1) , Imen El Karoui (1) , Sébastien Allali (1) , Joshua Hagège (1) , Katia Lehongre (2, 1) , Dominique Hasboun (3, 1) , Michel Baulac (4, 1, 3) , Stéphane Epelbaum (1, 4) , Agnès Michon (4) , Bruno Dubois (1, 3, 4) , Vincent Navarro (4, 1, 3, 4) , Moti Salti (5) , Lionel Naccache (1, 3, 4, 4)

1 ICM - Institut du Cerveau et de la Moëlle Epinière = Brain and Spine Institute
2 CENIR - Plateforme de neuroimagerie CENIR = Center for NeuroImaging Research-Human MRI Neuroimaging core facility for clinical research [ICM Paris]
3 UPMC - Université Pierre et Marie Curie - Paris 6 - UFR de Médecine Pierre et Marie Curie
4 CHU Pitié-Salpêtrière [AP-HP]
5 BGU - Ben-Gurion University of the Negev

The notion that past choices affect preferences is one of the most influential concepts of social psychology since its first report in the 50 s, and its theorization within the cognitive dissonance framework. In the free-choice paradigm (FCP) after choosing between two similarly rated items, subjects reevaluate chosen items as more attractive and rejected items as less attractive. However the relations prevailing between episodic memory and choice-induced preference change (CIPC) remain highly debated: is this phenomenon dependent or independent from memory of past choices? We solve this theoretical debate by demonstrating that CIPC occurs exclusively for items which were correctly remembered as chosen or rejected during the choice stage. We used a combination of fMRI and intra-cranial electrophysiological recordings to reveal a modulation of left hippocampus activity, a hub of episodic memory retrieval, immediately before the occurrence of CIPC during item reevaluation. Finally, we show that contrarily to a previous influential report flawed by a statistical artifact, this phenomenon is absent in amnesic patients for forgotten items. These results demonstrate the dependence of cognitive dissonance on conscious episodic memory. This link between current preferences and previous choices suggests a homeostatic function of this regulative process, aiming at preserving subjective coherence.

Domaines: Médecine humaine et pathologie

Mariam Chammat, Imen El Karoui, Sébastien Allali, Joshua Hagège, Katia Lehongre, et al.. Cognitive dissonance resolution depends on episodic memory. Scientific Reports, 2017, 7, pp.41320. ⟨10.1038/srep41320⟩. ⟨hal-01449795⟩