Face Motion Form at Learning Influences the Time Course of Face Spatial Frequency Processing during Test.

Studies that use static faces suggest that facial processing follows a coarse-to-fine sequence; i.e., holistic precedes featural processing, due to low and high spatial frequencies (LSF, HSF) transmitting holistic/global and featural/local information respectively. Although recent studies have focused on the role of facial movement in holistic facial processing, it is unclear whether moving faces have the same processing mechanism as static ones, especially in the time course of processing. The current study uses the event-related potential technique to investigate this issue by manipulating the facial format at study and face spatial frequency during the test. ERP results showed that the P1 amplitude was increased by LSF faces relative to HSF ones, using both moving and static study faces, with the former larger than the latter. The N170 amplitude was more sensitive to HSF than LSF faces when only static study faces were used, while the P2 amplitude was more sensitive to LSF faces regardless of the facial study format. The above results were not modulated by the race of the faces. These results favor the view that regardless of face race, moving study faces promote holistic processing during the earliest stage of face recognition. Furthermore, holistic processing is observed to be the same for both static and moving study faces at a later stage associated with more in-depth processing. It is evident that facial motion should be factored into further studies of face recognition, given the distinctions between holistic and featural processing for moving and static study faces.