title: Effective Connectivity Reveals Largely Independent Parallel Networks of Face and Body Patches.
abstract: The primate brain processes objects in the ventral visual pathway. One object category, faces, is processed in a hierarchical network of interconnected areas along this pathway. It remains unknown whether such an interconnected network is specific for faces or whether there are similar networks for other object classes. For example, the primate inferotemporal cortex also contains a set of body-selective patches, adjacent to the face-selective patches, but it is not known whether these body-selective patches form a similar discretely connected network or whether cross-talk exists between the face- and body-processing systems. To address these questions, we combined fMRI with electrical microstimulation to determine the effective connectivity of fMRI-defined face and body patches. We found that microstimulation of face patches caused increased fMRI activation throughout the face-processing system; microstimulation of the body patches gave similar results restricted to the body-processing system. Critically, our results revealed largely segregated connectivity patterns for the body and face patches. These results suggest that face and body patches form two interconnected hierarchical networks that are largely separated within the monkey inferotemporal cortex. Only a restricted number of voxels were activated by stimulation of both the body and face patches. The latter regions may be important for the integration of face and body information. Our findings are not only essential to advance our understanding of the neural circuits that enable social cognition, but they also provide further insights into the organizing principles of the inferotemporal cortex.
authors.affiliation: Laboratorium voor Neuro- en Psychofysiologie, KU Leuven, 3000 Leuven, Belgium.
authors.forename: Elsie
authors.initials: E
authors.lastname: Premereur
authors.affiliation: Laboratorium voor Neuro- en Psychofysiologie, KU Leuven, 3000 Leuven, Belgium.
authors.forename: Jessica
authors.initials: J
authors.lastname: Taubert
authors.affiliation: Laboratorium voor Neuro- en Psychofysiologie, KU Leuven, 3000 Leuven, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Janssen
authors.affiliation: Laboratorium voor Neuro- en Psychofysiologie, KU Leuven, 3000 Leuven, Belgium. Electronic address: rufin.vogels@kuleuven.be.
authors.forename: Rufin
authors.initials: R
authors.lastname: Vogels
authors.affiliation: Laboratorium voor Neuro- en Psychofysiologie, KU Leuven, 3000 Leuven, Belgium; Department of Radiology, Harvard Medical School, Boston, MA 02115, USA; MGH Martinos Center for Biomedical Imaging, Charlestown, MA 02129, USA. Electronic address: wim@nmr.mgh.harvard.edu.
authors.forename: Wim
authors.initials: W
authors.lastname: Vanduffel
mesh_terms: D001931:Brain Mapping; D004558:Electric Stimulation; D004594:Electrophysiology; D005145:Face; D005556:Form Perception; D006801:Humans; D008279:Magnetic Resonance Imaging; D010364:Pattern Recognition, Visual; D021641:Recognition, Psychology; D014795:Visual Pathways
keywords: body-selective areas; connectivity; effective connectivity; extrastriate visual cortex; fMRI; face areas; macaque; microstimulation; monkey; networks