Although the functional properties of these areas have been studied extensively, we do not yet have a comprehensive understanding of how the face-processing network functions in a dynamic manner. Similarly, a number of so-called face patches have been identified in macaque monkeys along the superior temporal sulcus ( Tsao et al., 2003 Tsao et al., 2006 Tsao et al., 2008). Three bilateral face-selective areas are considered as the core face-processing system, defined in functional Magnetic Resonance Imaging (fMRI) studies as regions showing significantly higher response to faces than objects, which are Occipital Face Area (OFA) in the inferior occipital gyrus ( Gauthier et al., 2000 Haxby et al., 1999), Fusiform Face Area (FFA) in the fusiform gyrus ( Kanwisher et al., 1997 Grill-Spector et al., 2004) and a face-sensitive area in the posterior superior temporal sulcus (pSTS) ( Hoffman and Haxby, 2000 Puce et al., 1998). There is ample evidence to show that the processing of face information involves a distributed neural network of face-sensitive areas in the occipitotemporal cortex and beyond ( Duchaine and Yovel, 2015 Haxby et al., 2000). Together, our findings chronicle the precise timing of bottom-up, top-down, as well as context-facilitated processing sequences in the occipital-temporal face network, highlighting the importance of the top-down operations especially when faced with incomplete or ambiguous input. Further, face-specific responses elicited by contextual cues alone emerged simultaneously in the right ventral face-selective regions, suggesting parallel contextual facilitation. However, processing of two-tone Mooney faces lacking explicit prototypical facial features engaged top-down projection from the right posterior fusiform face area to right occipital face area. This bottom-up processing sequence was also observed even when internal facial features were misarranged. Processing of normal faces started in the posterior occipital areas and then proceeded to anterior regions. ![]() Here, we uncovered the timing of activation in core face-selective regions using functional Magnetic Resonance Imaging and Magnetoencephalography in humans. Although face processing has been studied extensively, the dynamics of how face-selective cortical areas are engaged remains unclear.
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