The functional role of the frontal face patches in face perception.

Facial information is critically important for guiding interactions among conspecifics of many social species, including humans. In primates, an extensive network of interconnected brain areas processes such facial information. This face-processing network comprises several well-studied ventral stream areas, but also some prefrontal regions whose functional characteristics, connectivity and functional role in face perception are severely understudied. Therefore, we propose a series of experiments to i) map category-selectivity of frontal cortex and characterize the responses of frontal face patches using state-of-the-art sub-mm fMRI and single-unit recordings. ii) Guided by these maps, we will investigate how frontal face patches are effectively connected with the rest of the face processing network using a combination of fMRI and microstimulation. iii) Finally, we will determine whether the frontal face patches are causally involved in shaping face-selective responses in occipital face patches, and in face identification. To this end, we will perturb the activity of frontal face patches with hyperpolarizing red-shifted opsins during face-identification, and passive viewing tasks aimed to dissect specific types of facial processing (configuration and feature signals). Our results will provide key insights about the mesoscopic functional layout and effective connectivity of the largely understudied frontal face processing network and its functional role in face perception.