Cytoarchitectonic mapping of the human dorsal extrastriate cortex

C. & O. Vogt Institute for Brain Research, University of Düsseldorf, Düsseldorf, Germany.
Brain Structure and Function (Impact Factor: 5.62). 02/2012; 218(1). DOI: 10.1007/s00429-012-0390-9
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ABSTRACT The dorsal visual stream consists of several functionally specialized areas, but most of their cytoarchitectonic correlates have not yet been identified in the human brain. The cortex adjacent to Brodmann area 18/V2 was therefore analyzed in serial sections of ten human post-mortem brains using morphometrical and multivariate statistical analyses for the definition of areal borders. Two previously unknown cytoarchitectonic areas (hOc3d, hOc4d) were detected. They occupy the medial and, to a smaller extent, lateral surface of the occipital lobe. The larger area, hOc3d, is located dorso-lateral to area V2 in the region of superior and transverse occipital, as well as parieto-occipital sulci. Area hOc4d was identified rostral to hOc3d; it differed from the latter by larger pyramidal cells in lower layer III, thinner layers V and VI, and a sharp cortex-white-matter borderline. The delineated areas were superimposed in the anatomical MNI space, and probabilistic maps were calculated. They show a relatively high intersubject variability in volume and position. Based on their location and neighborhood relationship, areas hOc3d and hOc4d are putative anatomical substrates of functionally defined areas V3d and V3a, a hypothesis that can now be tested by comparing probabilistic cytoarchitectonic maps and activation studies of the living human brain.

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Available from: Simon B Eickhoff, Jan 23, 2014
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    • "Regions of interest ( ROIs ) were taken from the literature ( Geyer et al . , 1999 , 2000 ; Amunts et al . , 2000 ; Binkofski et al . , 2000 ; Rademacher et al . , 2001 ; Rottschy et al . , 2007 ; Scheperjans et al . , 2008 ; Caspers et al . , 2010 , 2013 ; Kolster et al . , 2010 ; Kujovic et al . , 2013 ) ; they were defined as 6 - mm radius spheres in both hemispheres . We included 15 seeds to assess functional connectivity ( Table 2 , Figure 1 ) . These seeds were selected within the occipital cortex ( i . e . , V1 , V2 , hOC3V , hOC3D , hOC4V , hOC4D , MT / V5 , and fusiform gyrus ) , parietal cortex ( S1 , lateral BA5 , anterior BA"
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    Frontiers in Neuroanatomy 07/2015; 9:86. DOI:10.3389/fnana.2015.00086 · 3.54 Impact Factor
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    • "This probability is even lower than the critical uncorrected p threshold corresponding to a FWE-corrected threshold in a single image from our analysis (p \ 0.0000058). For anatomical localization of the functional data, we referred to probabilistic cytoarchitectonic maps (Eickhoff et al. 2005; Amunts et al. 2000; Malikovic et al. 2007; Kujovic et al. 2013). "
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    Brain Structure and Function 09/2014; DOI:10.1007/s00429-014-0898-2 · 5.62 Impact Factor
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    • "In V2d, V2v and V3d myelin density appears lower in the peripheral representation, but it is difficult to exclude systematic biases related to cortical folding and/or cortical thickness in these regions. Cytoarchitectonic differences have been reported between h0c3d and hOc3v (Kujovic et al., 2013). In the macaque, functional and architectonic differences between V3d and V3v have been reported , though of opposite polarity in terms of myeloarchitecture (Burkhalter et al., 1986), but V3d and V3v are now widely regarded as subdivisions of a single retinotopic area (Lyon and Kaas, 2002). "
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