An image-dependent representation of familiar and unfamiliar faces in the human ventral stream

Abstract

People are extremely proficient at recognizing faces that are familiar to them, but are much worse at matching unfamiliar faces. We used fMR-adaptation to ask whether this difference in recognition might be reflected by an image-invariant representation for familiar faces in face-selective regions of the human ventral visual processing stream. Consistent with models of face processing, we found adaptation to repeated images of the same face image in the fusiform face area (FFA), but not in the superior-temporal face region (STS). To establish if the neural representation in the FFA was invariant to changes in view, we presented different images of the same face. Contrary to our hypothesis, we found that the response in the FFA to different images of the same person was the same as the response to images of different people. A group analysis showed a distributed pattern of adaptation to the same image of a face, which extended beyond the face-selective areas, including other regions of the ventral visual stream. However, this analysis failed to reveal any regions showing significant image-invariant adaptation. These results suggest that information about faces is represented in a distributed network using an image-dependent neural code.