Mechanisms of Long-Term Nonexternally Reinforced Preference Change: Functional Connectivity Changes in a Longitudinal Functional MRI Study.

Behavioral change studies mostly focus on external reinforcements to modify preferences. Cue-approach training (CAT) is a paradigm that influences preferences by the mere association of stimuli, sensory cues, and a rapid motor response, without external reinforcements. The behavioral effect has been shown to last for months after less than 1 h of training. Here, we used a modified version of CAT by changing the neutral-cue to a number that represented a monetary amount of reward that the participants accumulate (i.e., incentive-cue). After a single training session, we compared behavioral performance and functional connectivity (FC), as measured by resting-state scans using functional magnetic resonance imaging, between two groups (total of 107 males and females in both groups), one receiving a neutral-cue and the other receiving an incentive-cue, at five time points across 1 year. We replicated the maintenance of behavioral changes after 6 months for the nonexternally reinforced neutral-cue participants, but not for the reinforced group. The reinforced training group showed higher FC within the limbic system, whereas the nonexternally reinforced group showed higher functional connectivity within and between default mode and dorsal attention networks. Our findings offer putative neural correlates for both reinforced and nonexternally reinforced preference changes that are maintained over time and which could be implemented in future behavioral change interventions.