Contribution of Top and Bottom Part of a Face to the Perception of Facial Expressions: A Gaze-Contingency Investigation

Abstract

It is widely believed that face recognition is achieved via holistic processing of the representation integrated over parts of a face. In contrast, processing of facial expressions can be undertaken based on representation of separate parts. In three experiments we examined contribution of top and bottom part of a face to the perception of facial expressions. In Experiment 1, we examined the role that top and bottom part of a face may play in perceiving emotional expression by combining an expressive half with an emotionally congruent half or a neutral half, in comparison to a half face being presented alone. Results showed the bottom part of a face (typically with a smiling mouth) played a dominant role in expressing happiness, whereas the top part appeared to play an influential role in expressing sadness. For the remaining expressions, neither the top nor bottom part played a distinct role. In Experiment 2, we employed gaze contingency to (a) replicate the findings by Calvo and his colleagues that a smiling mouth could dominate the perception of happy expression (Calvo, Fernández-Martín, & Nummenmaa, 2013), and (b) extend the finding to see whether the top half would play a similar role in the perception of sad expression. The results, while replicating Calvo et al.'s overall findings, revealed that the role of top part in expressing sadness was less straightforward. Finally, in Experiment 3, we explicitly directed participants' attention to the top part of a sad face and found that the top part required focal attention in order for it to affect the expression of sadness. Taken together, these results suggest that the contribution of top and bottom part of a face to the perception of facial expression may vary between holistic and part-based processing, depending upon the nature of specific emotions to be conveyed. Meeting abstract presented at VSS 2016