title: Resting-state connectivity and functional specialization in human medial parieto-occipital cortex.
abstract: According to recent models of visuo-spatial processing, the medial parieto-occipital cortex is a crucial node of the dorsal visual stream. Evidence from neurophysiological studies in monkeys has indicated that the parieto-occipital sulcus (POS) contains three functionally and cytoarchitectonically distinct areas: the visual area V6 in the fundus of the POS, and the visuo-motor areas V6Av and V6Ad in a progressively dorsal and anterior location with respect to V6. Besides different topographical organization, cytoarchitectonics, and functional properties, these three monkey areas can also be distinguished based on their patterns of cortico-cortical connections. Thanks to wide-field retinotopic mapping, areas V6 and V6Av have been also mapped in the human brain. Here, using a combined approach of resting-state functional connectivity and task-evoked activity by fMRI, we identified a new region in the anterior POS showing a pattern of functional properties and cortical connections that suggests a homology with the monkey area V6Ad. In addition, we observed distinct patterns of cortical connections associated with the human V6 and V6Av which are remarkably consistent with those showed by the anatomical tracing studies in the corresponding monkey areas. Consistent with recent models on visuo-spatial processing, our findings demonstrate a gradient of functional specialization and cortical connections within the human POS, with more posterior regions primarily dedicated to the analysis of visual attributes useful for spatial navigation and more anterior regions primarily dedicated to analyses of spatial information relevant for goal-directed action.
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, G. D'Annunzio University, Via dei Vestini, 33, 66013, Chieti, Italy. annalisa.tosoni@hotmail.com.|Institute for Advanced Biomedical Technologies "ITAB", G. D'Annunzio Foundation, Chieti, Italy. annalisa.tosoni@hotmail.com.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Tosoni
authors.affiliation: Department of Motor, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy.|Laboratory of Neuropsychology, Santa Lucia Foundation, Rome, Italy.
authors.forename: Sabrina
authors.initials: S
authors.lastname: Pitzalis
authors.affiliation: Department of Neuroscience, Imaging and Clinical Sciences, G. D'Annunzio University, Via dei Vestini, 33, 66013, Chieti, Italy.|Institute for Advanced Biomedical Technologies "ITAB", G. D'Annunzio Foundation, Chieti, Italy.
authors.forename: Giorgia
authors.initials: G
authors.lastname: Committeri
authors.affiliation: Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Fattori
authors.affiliation: Department of Pharmacy and Biotechnology, University of Bologna, Bologna, Italy.
authors.forename: Claudio
authors.initials: C
authors.lastname: Galletti
authors.affiliation: Laboratory of Neuropsychology, Santa Lucia Foundation, Rome, Italy.|Department of Psychology, Sapienza University, Rome, Italy.
authors.forename: Gaspare
authors.initials: G
authors.lastname: Galati
mesh_terms: D000328:Adult; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009778:Occipital Lobe / Q000502:physiology*; D010296:Parietal Lobe / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D013329:Structure-Activity Relationship; D014793:Visual Cortex / Q000502:physiology; D014795:Visual Pathways / Q000502:physiology*
keywords: Functional connectivity MRI; V6Av–V6Ad; Visual area V6; Visuo-motor area V6A