The influence of social cues in learning and decision-making over time.

Introduction: Initial visual impressions guide judgment and decision-making in social contexts, and social cues, such as facial trustworthiness, may bias choices by influencing individuals to prioritize appearance over actual behavioral outcomes. Key challenges for research in this field include clarifying the extent to which decision-making and learning under uncertainty are affected (1) by facial cues of trustworthiness vs. untrustworthiness, (2) by the congruence vs. incongruence of face-based visual cues and behavioral outcomes, and (3) in a social relative to a non-social decision context. Methods: This study used the Social Iowa Gambling Task (S-IGT), an adaptation of the Iowa Gambling Task (IGT). Extending traditional decision-making paradigms by systematically integrating several novel aspects, the S-IGT features: (1) the experimental manipulation of facial cues perceived as trustworthy vs. untrustworthy and (2) the incorporation of decision options paired with congruent (CS-IGT) vs. incongruent (IS-IGT) social cues; and was used here in combination with (3) a non-social/neutral control condition (the standard IGT). Results: Across 558 participants, we found that initial performance in the CS-IGT was higher than in the other two task conditions, yet participants' learning progress diminished over time in the CS-IGT. Discussion: These findings suggest that while social cues of facial trustworthiness may support early decision-making, they also may encourage reliance on initial impressions over feedback-driven exploration, thus crucially influencing choice and learning trajectories under uncertainty in social contexts. The results further highlight the complex role of visual facial and behavior-based information congruence vs. incongruence in dynamic social decision environments.