Response properties of the human fusiform face area.

We used functional magnetic resonance imaging to study the response properties of the human fusiform face area (FFA: Kanwisher, McDermott, & Chun, 1997) to a variety of face-like stimuli in order to clarify the functional role of this region. FFA responses were found to be (1) equally strong for cat, cartoon and human faces despite very different image properties, (2) equally strong for entire human faces and faces with eyes occluded but weaker for eyes shown alone, (3) equal for front and profile views of human heads, but declining in strength as faces rotated away from view, and (4) weakest for nonface objects and houses. These results indicate that generalisation of the FFA response across very different face types cannot be explained in terms of a specific response to a salient facial feature such as the eyes or a more general response to heads. Instead, the FFA appears to be optimally tuned to the broad category of faces.