The investigation of the effect of emotion on rule-based and similarity-based categorization processes in the context of appraisal tendency framework

Previous research based on the appraisal tendency framework (Lerner, & Keltner, 2000, 2001) showed that emotions associated with certainty appraisals increase the tendency to use intuitive strategies, heuristics, and biasing cues; whereas uncertainty-associated emotions increase the need for extra information, and lead to deliberative processing in reasoning and decision making tasks (e.g., Bagneux et al., 2012, 2013; Bollon, & Bagneux, 2013; Tiedens, & Linton, 2001). In the present study, we aimed to test the modulatory effects of emotional (un)certainty on a different cognitive domain, i.e. rule-based versus similarity-based categorization processes. In accordance with this purpose, we conducted four experiments using the categorization task introduced by Brooks and colleagues (Allen, & Brooks, 1991; Regehr, & Brooks, 1993). Specifically, participants were given a perfectly predictive classification rule, and asked to categorize the stimuli according to that rule by receiving feedbacks. After the training phase, their emotional state was manipulated, and they performed the test phase without receiving feedbacks. We hypothesized that, participants in the certainty-associated emotion conditions would rely more on similarity-based categorization processes, whereas participants in the uncertainty conditions would tend to use rule-based categorization processes. The results were mostly in the expected direction, demonstrating that in comparison with certainty-associated emotions (i.e., disgust and happiness), uncertainty-associated emotions (i.e., fear and fear/anxiety) decreased the exemplar effects, and enhanced the reliance on rule-based strategies while categorizing the transfer stimuli in the test phase. The findings were discussed in the frame of emotional theories, and depth of processing models.