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A Locus in Human Extrastriate Cortex for Visual Shape Analysis
A Locus in Human Extrastriate Cortex for Visual Shape Analysis Nancy Kanwisher Harvard University Roger P. Woods, Marco Iacoboni, and John C. Mazziotta Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/9/1/133/1755424/jocn.1997.9.1.133.pdf by guest on 18 May 2021 University of California, Los Angeles Abstract Positron emission tomography (PET) was used to locate an fusiform gyms) when subjects viewed line drawings of area in human extrastriate cortex that subserves a specific 3dimensional objects compared to viewing scrambled draw- component process of visual object recognition. Regional ings with no clear shape interpretation. Responses were Seen blood flow increased in a bilateral extrastriate area on the for both novel and familiar objects, implicating this area in inferolateral surface of the brain near the border between the the bottom-up (i.e., memory-independent) analysis of visual occipital and temporal lobes (and a smaller area in the right shape. INTRODUCTION 1980; Glaser & Dungelhoff, 1984). Such efficiency and automaticity are characteristic of modular processes (Fo- Although neurophysiological studies over the last 25 dor, 1983). Second, abilities critical for survival (such as years have provided a richly detailed map of the 30 or rapid and accurate object recognition) are the ones most more different visual areas of the macaque brain (Felle- likely to be refined by natural selection through the man & Van Essen, 1991), the mapping of human visual construction of innate and highly specialized brain mod- cortex -
Traveling Cortical Netwaves Compose a Mindstream
bioRxiv preprint doi: https://doi.org/10.1101/705947; this version posted April 29, 2020. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC 4.0 International license. Traveling cortical netwaves compose a mindstream Ernst Rudolf M. Hülsmann 26 Rue de Bonn. CH-3186 Guin. Switzerland. [email protected] ABSTRACT The brain creates a physical response out of signals in a cascade of streaming transformations. These transfor- mations occur over networks, which have been described in anatomical, cyto-, myeloarchitectonic and functional research. The totality of these networks has been modelled and synthesised in phases across a continuous time- space-function axis, through ascending and descending hierarchical levels of association1-3 via changing coalitions of traveling netwaves4-6, where localised disorders might spread locally throughout the neighbouring tissues. This study quantified the model empirically with time-resolving functional magnetic resonance imaging of an imperative, visually-triggered, self-delayed, therefor double-event related response task. The resulting time series unfold in the range of slow cortical potentials the spatio-temporal integrity of a cortical pathway from the source of perception to the mouth of reaction in and out of known functional, anatomical and cytoarchitectonic networks. These pathways are consolidated in phase images described by a small vector matrix, which leads to massive simplification of cortical field theory and even to simple technical applications. INTRODUCTION On a first sight it seems to be self-evident that a local perturbation within the cortical sheet should spread locally. -
Mapping Striate and Extrastriate Visual Areas in Human Cerebral Cortex EDGAR A
Proc. Natl. Acad. Sci. USA Vol. 93, pp. 2382-2386, March 1996 Neurobiology Mapping striate and extrastriate visual areas in human cerebral cortex EDGAR A. DEYOE*, GEORGE J. CARMANt, PETER BANDETTINIt, SETH GLICKMAN*, JON WIESER*, ROBERT COX§, DAVID MILLER1, AND JAY NEITZ* *Department of Cellular Biology and Anatomy, and Biophysics Research Institute, The Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226; tThe Salk Institute for Biological Studies, La Jolla, CA 92037; tMassachusetts General Hospital-NMR Center, Charlestown, MA 02129; §Biophysics Research Institute, The Medical College of Wisconsin, Milwaukee, WI 53226; and lBrown University, Providence, RI 02912 Communicated by Francis Crick The Salk Institute for Biological Sciences, San Diego, CA, November 14, 1995 (received for review August 2, 1995) ABSTRACT Functional magnetic resonance imaging represented by each active site in the brain (12). A similar (fMRI) was used to identify and map the representation of the technique has been described by Engel et al. (15). visual field in seven areas of human cerebral cortex and to To enhance activation of extrastriate cortex (12) and to help identify at least two additional visually responsive regions. maintain attention and arousal, the subject was required to The cortical locations of neurons responding to stimulation detect a small target appearing at a random position super- along the vertical or horizontal visual field meridia were imposed on the checkered hemifield or annulus. A new target charted on three-dimensional models of the cortex and on was presented every 2 sec and the subject activated one of two unfolded maps of the cortical surface. -
Cytoarchitectonic Mapping of the Human Dorsal Extrastriate Cortex
Brain Struct Funct (2013) 218:157–172 DOI 10.1007/s00429-012-0390-9 ORIGINAL ARTICLE Cytoarchitectonic mapping of the human dorsal extrastriate cortex Milenko Kujovic • Karl Zilles • Aleksandar Malikovic • Axel Schleicher • Hartmut Mohlberg • Claudia Rottschy • Simon B. Eickhoff • Katrin Amunts Received: 23 September 2011 / Accepted: 31 January 2012 / Published online: 22 February 2012 Ó The Author(s) 2012. This article is published with open access at Springerlink.com Abstract The dorsal visual stream consists of several superimposed in the anatomical MNI space, and probabi- functionally specialized areas, but most of their cytoar- listic maps were calculated. They show a relatively high chitectonic correlates have not yet been identified in the intersubject variability in volume and position. Based on human brain. The cortex adjacent to Brodmann area 18/V2 their location and neighborhood relationship, areas hOc3d was therefore analyzed in serial sections of ten human post- and hOc4d are putative anatomical substrates of function- mortem brains using morphometrical and multivariate ally defined areas V3d and V3a, a hypothesis that can now statistical analyses for the definition of areal borders. be tested by comparing probabilistic cytoarchitectonic Two previously unknown cytoarchitectonic areas (hOc3d, maps and activation studies of the living human brain. hOc4d) were detected. They occupy the medial and, to a smaller extent, lateral surface of the occipital lobe. The Keywords Cytoarchitecture Á Visual cortex Á hOc3d Á larger area, hOc3d, is located dorso-lateral to area V2 in the hOc4d Á V3 Á V3a Á Probabilistic maps Á Human brain atlas region of superior and transverse occipital, as well as parieto-occipital sulci. -
Mapping Striate and Extrastriate Visual Areas in Human Cerebral Cortex EDGAR A
Proc. Natl. Acad. Sci. USA Vol. 93, pp. 2382-2386, March 1996 Neurobiology Mapping striate and extrastriate visual areas in human cerebral cortex EDGAR A. DEYOE*, GEORGE J. CARMANt, PETER BANDETTINIt, SETH GLICKMAN*, JON WIESER*, ROBERT COX§, DAVID MILLER1, AND JAY NEITZ* *Department of Cellular Biology and Anatomy, and Biophysics Research Institute, The Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226; tThe Salk Institute for Biological Studies, La Jolla, CA 92037; tMassachusetts General Hospital-NMR Center, Charlestown, MA 02129; §Biophysics Research Institute, The Medical College of Wisconsin, Milwaukee, WI 53226; and lBrown University, Providence, RI 02912 Communicated by Francis Crick The Salk Institute for Biological Sciences, San Diego, CA, November 14, 1995 (received for review August 2, 1995) ABSTRACT Functional magnetic resonance imaging represented by each active site in the brain (12). A similar (fMRI) was used to identify and map the representation of the technique has been described by Engel et al. (15). visual field in seven areas of human cerebral cortex and to To enhance activation of extrastriate cortex (12) and to help identify at least two additional visually responsive regions. maintain attention and arousal, the subject was required to The cortical locations of neurons responding to stimulation detect a small target appearing at a random position super- along the vertical or horizontal visual field meridia were imposed on the checkered hemifield or annulus. A new target charted on three-dimensional models of the cortex and on was presented every 2 sec and the subject activated one of two unfolded maps of the cortical surface. -
Topographic Organization of Human Visual Areas in the Absence of Input from Primary Cortex
The Journal of Neuroscience, April 1, 1999, 19(7):2619–2627 Topographic Organization of Human Visual Areas in the Absence of Input from Primary Cortex Heidi A. Baseler,1 Antony B. Morland,1,2 and Brian A. Wandell1 1Psychology Department and Neuroscience Program, Stanford University, Stanford, California 94305, and 2Biophysics Section, Physics Department, Imperial College, London SW7 2BZ, United Kingdom Recently, there has been evidence for considerable plasticity in responses were found primarily in dorsal extrastriate areas. primary sensory areas of adult cortex. In this study, we asked to Furthermore, cortex that had formerly shown normal topogra- what extent topographical maps in human extrastriate areas phy now represented only the visual field around the lower reorganize after damage to a portion of primary visual (striate) vertical meridian. Several possible sources for this reorganized cortex, V1. Functional magnetic resonance imaging signals activity are considered, including transcallosal connections, were measured in a subject (G.Y.) with a large calcarine lesion direct subcortical projections to extrastriate cortex, and resid- that includes most of primary visual cortex but spares the foveal ual inputs from V1 near the margin of the lesion. A scheme is representation. When foveal stimulation was present, intact described to explain how the reorganized signals could occur cortex in the lesioned occipital lobe exhibited conventional based on changes in the local neural connections. retinotopic organization. Several visual areas could be identi- fied (V1, V2, V3, V3 accessory, and V4 ventral). However, when Key words: fMRI; retinotopy; visual areas; cortical plasticity; stimuli were restricted to the blind portion of the visual field, V1; hemianope A general view of brain development holds that some aspects of visual signals delivered to extrastriate cortical areas and presents neural development arise without the benefit of experience, an opportunity for considerable reorganization. -
Subdivision of the Occipital Lobes: an Anatomical and Functional MRI Connectivity Study
cortex xxx (2012) 1e17 Available online at www.sciencedirect.com Journal homepage: www.elsevier.com/locate/cortex Special issue: Research report Subdivision of the occipital lobes: An anatomical and functional MRI connectivity study Michel Thiebaut de Schotten a,b,c,d,*, Marika Urbanski b,c,f, Romain Valabregue b,c,d,e, Dimitri J. Bayle c and Emmanuelle Volle b,c a Natbrainlab, Department of Forensic and Neurodevelopmental Sciences, Institute of Psychiatry, King’s College London, London, UK b Universite´ Pierre et Marie Curie-Paris 6, Centre de Recherche de l’Institut du Cerveau et de la Moelle e´pinie`re (CRICM), UMRS 975, Paris, France c Inserm, U 975, Paris, France d CNRS, UMR 7225, Paris, France e Centre de Neuroimagerie de Recherche CENIR, Groupe Hospitalier Pitie´-Salpeˆtrie`re, Paris, France e Service de Me´decine et de Re´adaptation, Hoˆpitaux de Saint-Maurice, Saint-Maurice, France article info abstract Article history: Exploring brain connectivity is fundamental to understanding the functional architecture Received 28 May 2012 of the cortex. In our study we employed tractography-based parcellation, combined with Reviewed 3 July 2012 the principal component analysis statistical framework, to divide the occipital lobes into Revised 24 September 2012 seven areas in a group of eighteen healthy participants. Tractography-based parcellation is Accepted 6 December 2012 a method based on diffusion imaging tractography, which segregates the living human Published online xxx brain into distinctive areas showing sharp differences in their anatomical connectivity. The results were compared to covarying functional networks involving distinct areas Keywords: within the occipital lobes, that we obtained using resting state functional magnetic reso- Anatomy nance imaging (fMRI), as well as to other existing subdivisions of the occipital lobes.