Come closer if you dare: A validation of the revised Reinforcement Sensitivity Theory by behavioral responses to positive and negative stimuli

The revised Reinforcement Sensitivity Theory (rRST) is an influential personality theory that provides explanations for differences in approach and avoidance tendencies. In this study, we aim to test assumptions of the rRST, originally developed using animal models, in an experimental setting with humans. Therefore, we designed a paradigm in which N = 65 healthy participants are confronted with positive and negative images to measure their unconscious change in distance to the computer screen by means of a face recognition software. Persons with a more sensitive fight-flight-freezing system (FFFS; constituting fear, regulating avoidance) showed stronger distancing from negative images relative to positive images than people with a less sensitive FFFS. The behavioral inhibition system (BIS; constituting anxiety) showed no moderation on distance change, indicating that the systems underlying fear and anxiety adopt different regulatory functions. Concerning the behavioral approach system (BAS; regulating approach), also no effects were observed, although a BAS-dependent approach to positive stimuli was hypothesized. However, there was a main effect of picture valence, indicating closer distances for more positive stimuli. Overall, our data provide further evidence for the validity of the rRST, using the change in distance to the monitor as exciting operationalization of approach and avoidance behavior.