Evaluative conditioning shapes affective face perception and approach responses: A behavioral and eye movement study

The emotional significance of social stimuli can be manipulated through Evaluative Conditioning (EC), a form of associative learning where an object's subjective value changes - becoming more liked or disliked - due to its repeated pairing with positive or negative stimuli. For example, through repeated pairings with negative stimuli, unfamiliar faces acquire aversive value, resulting in decreased liking and increased avoidance behavior (Schlund et al., 2021). However, EC in relation to positive social stimuli remains unexplored. In this context, the present study aims to investigate whether the association of unfamiliar neutral faces with positive verbal stimuli alters their affective evaluation and motivational responses to approaching unfamiliar individuals. Ten healthy young adults (18–35 years) completed a two-day protocol including Face Assessment Task (FAT) and Approach–Avoidance Task (AAT) before (t0) and after (t1) being exposed to videos where unfamiliar faces were paired with rewarding (CS+) or neutral (CS-) visual and verbal stimuli. Behavioral measures included face ratings and eye movements within facial regions of interest (FAT), as well as reaction time, movement duration, final picture size, and accuracy (AAT). At t1 compared to t0, preliminary results show faster pull responses and reduced avoidance toward conditioned faces, along with increased ratings of trustworthiness and likeability. Eye-tracking data indicated longer dwell times on the eye region. Overall, these findings suggest that positive evaluative conditioning reshapes motivational and evaluative responses to social stimuli, and they provide a framework for developing interventions to strengthen adaptive social motivation in conditions characterized by reduced social engagement.