title: Functional Subdomains within Scene-Selective Cortex: Parahippocampal Place Area, Retrosplenial Complex, and Occipital Place Area.
abstract: Functional MRI studies suggest that at least three brain regions in human visual cortex-the parahippocampal place area (PPA), retrosplenial complex (RSC), and occipital place area (OPA; often called the transverse occipital sulcus)-represent large-scale information in natural scenes. Tuning of voxels within each region is often assumed to be functionally homogeneous. To test this assumption, we recorded blood oxygenation level-dependent responses during passive viewing of complex natural movies. We then used a voxelwise modeling framework to estimate voxelwise category tuning profiles within each scene-selective region. In all three regions, cluster analysis of the voxelwise tuning profiles reveals two functional subdomains that differ primarily in their responses to animals, man-made objects, social communication, and movement. Thus, the conventional functional definitions of the PPA, RSC, and OPA appear to be too coarse. One attractive hypothesis is that this consistent functional subdivision of scene-selective regions is a reflection of an underlying anatomical organization into two separate processing streams, one selectively biased toward static stimuli and one biased toward dynamic stimuli.
  
  
  
  Visual scene perception is a critical ability to survive in the real world. It is therefore reasonable to assume that the human brain contains neural circuitry selective for visual scenes. Here we show that responses in three scene-selective areas-identified in previous studies-carry information about many object and action categories encountered in daily life. We identify two subregions in each area: one that is selective for categories of man-made objects, and another that is selective for vehicles and locomotion-related action categories that appear in dynamic scenes. This consistent functional subdivision may reflect an anatomical organization into two processing streams, one biased toward static stimuli and one biased toward dynamic stimuli.
authors.affiliation: Department of Electrical and Electronics Engineering, Ulusal Manyetik Rezonans Araştırma Merkezi, Sabuncu Brain Research Center, and Neuroscience Program, Bilkent University, Ankara 06800, Turkey, cukur@ee.bilkent.edu.tr gallant@berkeley.edu.
authors.forename: Tolga
authors.initials: T
authors.lastname: Çukur
authors.affiliation: Helen Wills Neuroscience Institute.
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Huth
authors.affiliation: Graduate School of Frontier Biosciences, Osaka University, Osaka 565-0871, Japan, and.
authors.forename: Shinji
authors.initials: S
authors.lastname: Nishimoto
authors.affiliation: Helen Wills Neuroscience Institute, Program in Bioengineering, and Department of Psychology, University of California, Berkeley, California 94720 cukur@ee.bilkent.edu.tr gallant@berkeley.edu.
authors.forename: Jack L
authors.identifier: 0000-0001-7273-1054
authors.initials: JL
authors.lastname: Gallant
mesh_terms: D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology*; D003142:Communication; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008959:Models, Neurological; D009068:Movement; D009778:Occipital Lobe / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D020534:Parahippocampal Gyrus / Q000502:physiology*; D010775:Photic Stimulation; D055815:Young Adult
chemical_list: D010100:Oxygen
keywords: OPA; PPA; RSC; category representation; fMRI; scene; subdomain; tuning profile; voxelwise model