Distinct effects of monetary versus social reward magnitudes on the emotional congruency effect in subclinical depression: a word-face Stroop study

Background: Although incentives modulate cognitive processes, their differential effects of monetary versus social reward gradients on emotional conflict resolution in subclinical depression remain poorly understood. This study investigated how reward type and magnitude influence emotional congruency effects in this population. Methods: Two experiments used a word-face Stroop paradigm with a Latin square design. Ninety-nine undergraduates (47 with subclinical depression) completed monetary (0, 20, 100, 500 CNY) and social (no praise to university-level praise) reward tasks. A mixed-design ANOVA examined effects of reward level, emotional congruency, and group. Results: The subclinical depression group showed reduced emotional congruency, marked by lower accuracy in congruent trials than controls. Monetary rewards exhibited a threshold effect: accuracy gains plateaued beyond 100 CNY with no further improvement at 500 CNY. Social reward modulation was similar between groups, though reaction times under class-level praise were significantly higher in incongruent trials. Notably, under high monetary rewards (500 CNY), the subclinical group demonstrated shorter reaction times in congruent trials, indicating heightened sensitivity to substantial incentives. Conclusion: Emotional conflict processing in subclinical depression is differentially modulated by reward type and magnitude. Monetary rewards show saturating effects, while social rewards elicit uniform nonlinear influences. These findings highlight reward sensitivity as a crucial factor for cognitive-affective profiling and targeted interventions.