Stimuli with a positive valence can facilitate cognitive control

In the process of interacting with people and objects, humans assign affective valence. By using an association-transfer paradigm, the current study investigated whether the emotion associated with a stimulus would have an impact on cognitive control outcomes. During the association phase of two experiments reported here, participants identified the emotion expressed by an actor's face as either positive (i.e., smiling) or negative (i.e., frowning). Half of the actors expressed positive emotions (MP) on 80% of trials, while the other half expressed negative emotions (MN) on 80% of trials. We tested the cognitive effect of these associations in two experiments. In the transfer phase of Experiment 1, the same actors from the association phase were shown with neutral expression during a gender Stroop task, requiring participants to identify the gender of the face while ignoring a gender word (congruent or incongruent) that was imposed upon the face. The Stroop effect was significant for the MN faces, but the effect disappeared for the MP faces. In the transfer phase of Experiment 2, the emotionless faces were presented in a task-switching paradigm, in which participants identified the age (i.e., old or young) or the gender depending on the task cue. The task switch cost was smaller (though significant) for the MP faces than for the MN faces. These results suggest that, relative to social stimuli associated with negative expressions, social stimuli associated with positive expressions can promote better cognitive control and inhibit distractor interference in goal-oriented behavior.