Time pressure inhibits dynamic advantage in the classification of facial expressions of emotion

Recent studies suggest an advantage in the recognition of dynamic over static facial expressions of emotion. Here, we explored the differences in the processing of static and dynamic faces under condition of time pressure. A group of 18 participants classified static and dynamic facial expressions (angry, happy, and neutral). In order to increase the goal-directed attention, instructions emphasized speed and announced time pressure in the interval for the response (maximal 600 ms). Participants responded faster and more accurately in the static than in the dynamic condition. Event-related potentials (ERPs) showed larger amplitude of the P1 (90-130 ms) and LPC (300-600 ms) components for dynamic relative to static stimuli, indicating enhanced early visual processing and emotional attention. On the other hand, the N170 was more negative in static relative to dynamic faces, suggesting better structural encoding for static faces under time pressure. The present study shows some advantages in the processing of static over dynamic facial expressions of emotion when the top-down (goal-driven) attention is strengthened.