Perception of Natural and Artificial Dynamic Facial Expressions During Stroboscopic Presentation

Abstract

In an experimental study, we explored the role of the natural or artificial character of expression and the speed of its exposure in the recognition of emotional facial expressions during stroboscopic presentation. In Series 1, participants identified emotions represented as sequences of frames from a video of a natural facial expression; in Series 2 participants were shown sequences of linear morph images. The exposure speed was varied. The results showed that at any exposure speed, the expressions of happiness and disgust were recognized most accurately. Longer presentation increased the accuracy of assessments of happiness, disgust, and surprise. Expression of surprise, demonstrated as a linear transformation, was recognized more efficiently than frames of natural expression of surprise. Happiness was perceived more accurately on video frames. The accuracy of the disgust recognition did not depend on the type of images. The qualitative nature of the stimuli and the speed of their presentation did not affect the accuracy of sadness recognition. The categorical structure of the perception of expressions was stable in any type of exposed images. The obtained results suggest a qualitative difference in the perception of natural and artificial images of expressions, which can be observed under extreme exposure conditions.