High-resolution multi-voxel pattern analysis of category selectivity in the medial temporal lobes.

Although the parahippocampal cortex (PHc) is known to be critical for memory formation, little is known about what is encoded by this area. Using multi-voxel pattern analysis of high-resolution functional magnetic resonance imaging (MRI) data, we examined responses to blocks of categorically coherent stimuli and found that patterns of activity in PHc were selective for not only scenes, but also for other nonspatial object categories (e.g., faces and toys). This pattern of results was also found in the parahippocampal place area (PPA), indicating that this region is not sensitive exclusively to scenes. In contrast, neither the hippocampus nor perirhinal cortex (PRc) were found to be selective for category information. The results indicate that regions within the medial temporal lobe may support distinct functions, and that the PHc appears to be particularly sensitive to category-level information. (c) 2008 Wiley-Liss, Inc.