In Vivo Identification of Thick, Thin, and Pale Stripes of Macaque Area V2 Using Submillimeter Resolution (f)MRI at 3 T. (28th December 2017)

• Record Type: Journal Article
• Authors: Li, Xiaolian; Zhu, Qi; Janssens, Thomas; Arsenault, John T; Vanduffel, Wim
• Is Part Of: Cerebral cortex. Volume 29:Number 2(2019)
• Page Start: 544
• Page End: 560
• Publication Date: 2017-12-28
• Subjects: color -- columns -- disparity -- high-resolution fMRI -- myelin; Cerebral cortex -- Periodicals; Brain -- Periodicals; 612.825
• DOI: 10.1093/cercor/bhx337
• Languages: English
• ISSNs: 1047-3211

Abstract

Abstract: Primate area V2 contains a repetitive pattern of thick, thin and pale cytochrome oxidase stripes that are characterized by largely discrete in- and output channels, as well as differences in function, and myelo- and cytoarchitecture. Stripes have been identified mainly using microscope-based imaging of tiny portions of superficially located V2, or by postmortem methods, hence, the quest for (quasi) noninvasive tools to study these mesoscale functional units. Only recently, stripe-like V2 patterns have been demonstrated in humans with high-field (functional) magnetic resonance imaging (f)MRI, but in both such studies only 2 stripe compartments could be identified. Although interstripe distances in monkeys are ~half of those in humans, we show that all 3 V2 stripe classes can be reliably separated using submillimeter (f)MRI (0.6 mm isotropic voxels) on regular 3 T scanners by combining contrast agents and implanted phased-array coils. Specifically, we show highly reproducible fMRI patterns, both within and across subjects, of color-selective thin and disparity-selective thick stripes. Furthermore, reliable MRI-based higher myelin-density was observed in pale stripes. Hence, this is the first study showing segregation of columns using (f)MRI-based methods in macaque cortex, which opens the possibility of studying these elementary building blocks of the visual system noninvasively on a large scale.