Abstract
This study investigates perception for momentary changes in facial expressions using motion stimuli of faces. Within each set of motion stimuli, a facial expression showing either anger, sadness, or happiness was inserted momentarily, presented for either 130 ms, 220 ms, 330 ms, or 530 ms. One group of participants was asked to rate the level of pleasantness evoked by the complete set of stimuli, while a second group was asked to categorize the inserted facial expression as being happy, sad, angry, or neutral. Pleasantness ratings were higher when the inserted expression was happy compared to sad or angry. Categorization of the inserted facial expressions was quite accurate for angry and happy, but correct categorizations of angry were lower in the 130 ms condition. Although the pattern of results indicate that the participants were sensitive to momentary changes in facial expressions at durations of at least 200 ms, further research is needed to investigate why the perception of momentary changes varies for happy, angry and sad.
