THE COGNITIVE ALGEBRA OF PROTOTYPICAL EXPRESSIONS OF EMOTION IN THE FACE: ONE OR MANY INTEGRATION RULES?
Since the upsurge of face measurement systems, considerable knowledge has accumulated on the association of visible facial actions with the expression of given emotions. Much less is known on how these â€œaction unitsâ€ are integrated by observers who evaluate the emotional content of overall expressions. This issue exceeds the common concern with emotion recognition to address the many possible continuous judgment dimensions (intensity, naturalness, trustworthiness). FACS defined action units were implemented in synthetic faces, one male and one female, and taken as factors in a set of integration tasks asking for either intensity or naturalness judgments of the final expressions. Facial actions were selected from Ekmanâ€™s depiction of prototypes and major variants of emotion displays. A general additive integration rule was found across tasks and emotion categories, while the valuation of action units as informers varied according to the dimension of judgment.