title: The impact of orientation filtering on face-selective neurons in monkey inferior temporal cortex.
abstract: Faces convey complex social signals to primates. These signals are tolerant of some image transformations (e.g. changes in size) but not others (e.g. picture-plane rotation). By filtering face stimuli for orientation content, studies of human behavior and brain responses have shown that face processing is tuned to selective orientation ranges. In the present study, for the first time, we recorded the responses of face-selective neurons in monkey inferior temporal (IT) cortex to intact and scrambled faces that were filtered to selectively preserve horizontal or vertical information. Guided by functional maps, we recorded neurons in the lateral middle patch (ML), the lateral anterior patch (AL), and an additional region located outside of the functionally defined face-patches (CONTROL). We found that neurons in ML preferred horizontal-passed faces over their vertical-passed counterparts. Neurons in AL, however, had a preference for vertical-passed faces, while neurons in CONTROL had no systematic preference. Importantly, orientation filtering did not modulate the firing rate of neurons to phase-scrambled face stimuli in any recording region. Together these results suggest that face-selective neurons found in the face-selective patches are differentially tuned to orientation content, with horizontal tuning in area ML and vertical tuning in area AL.
authors.affiliation: Face Categorization Lab, University of Louvain, Louvain-La-Neuve 1348, Belgium.|Laboratorium voor Neuro- en Psychofysiologie, KU Leuven, Leuven 3000, Belgium.
authors.forename: Jessica
authors.initials: J
authors.lastname: Taubert
authors.affiliation: Face Categorization Lab, University of Louvain, Louvain-La-Neuve 1348, Belgium.
authors.forename: Valerie
authors.initials: V
authors.lastname: Goffaux
authors.affiliation: Face Categorization Lab, University of Louvain, Louvain-La-Neuve 1348, Belgium.
authors.forename: Goedele
authors.initials: G
authors.lastname: Van Belle
authors.affiliation: Laboratorium voor Neuro- en Psychofysiologie, KU Leuven, Leuven 3000, Belgium.|MGH Martinos Center, Charlestown, MA 02129, USA.|Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Wim
authors.initials: W
authors.lastname: Vanduffel
authors.affiliation: Laboratorium voor Neuro- en Psychofysiologie, KU Leuven, Leuven 3000, Belgium.
authors.forename: Rufin
authors.initials: R
authors.lastname: Vogels
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001931:Brain Mapping; D005145:Face; D008253:Macaca mulatta; D008279:Magnetic Resonance Imaging; D008297:Male; D009474:Neurons / Q000502:physiology*; D009949:Orientation; D010364:Pattern Recognition, Visual; D013702:Temporal Lobe / Q000502:physiology*