Abstract
Emotion results from our action, and in turn emotion affects our action. Previous research shows that social stimuli (e.g., human faces) associated with a high level of cognitive effort can acquire positive valence: Faces that frequently appear with incongruent distractors are subsequently recognized faster when the faces express positive rather than negative emotion. Emotion arising from social interaction involves recognition of others’ emotions, while emotion arising from non-social stimuli (e.g., sceneries, words) requires the retrieval of emotional appraisal. For example, a picture of a merry-go-round can only be “positive” when we retrieve the fun memories associated with the ride. The current study examined whether the effort-based valence evaluation is generalized to non-social stimuli. Participants performed the color Stroop task with item-specifically manipulated proportion congruency: Some colors were frequently presented as incongruent, effortful stimuli, while others as congruent, low-effort stimuli. Later, using these same colors as a prime, participants generated an emotional response toward neutral stimuli (Experiment 1), or recognized emotion of human faces (Experiment 2). The results show that high effort primes produced numerically higher positive responses in Experiment 1, and that low effort primes produced faster reaction time to positive than negative emotion in Experiment 2. These results suggest that the acquisition of positive valence is dependent on the category of stimulus “socialness”.