Abstract
Previous studies in rabbits identified an array of extrastriate cortical areas anatomically connected with V1 but did not describe their internal topography. To address this issue, we injected multiple anatomical tracers into different regions in V1 of the same animal and analyzed the topography of resulting extrastriate labeled fields with reference to the patterns of callosal connections and myeloarchitecture revealed in tangential sections of the flattened cortex. Our results extend previous studies and provide further evidence that rabbit extrastriate areas resemble the visual areas in rats and mice not only in their general location with respect to V1 but also in their internal topography. Moreover, extrastriate areas in the rabbit maintain a constant relationship with myeloarchitectonic borders and features of the callosal pattern. These findings highlight the rabbit as an alternative model to rats and mice for advancing our understanding of cortical visual processing in mammals, especially for projects benefiting from a larger brain.
Highlights
An important goal of visual system studies in animals is to understand vision in humans
Numerous studies in rats and mice have convincingly shown that the occipital cortex surrounding primary visual cortex (V1, striate cortex) is significantly more elaborate than previously thought, consisting of about a dozen of interconnected, topographically organized extrastriate visual areas [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]
In a group of albino rabbits we injected multiple distinguishable tracers into different regions of V1 in the same animal and analyzed the topography of resulting extrastriate labeled fields with reference to the patterns of callosal connections and myeloarchitecture revealed in tangential sections of the flattened cortex, an approach that has been fruitful for delineating the location and topography of extrastriate visual areas in several species [6, 7, 38]
Summary
An important goal of visual system studies in animals is to understand vision in humans. Numerous studies in rats and mice have convincingly shown that the occipital cortex surrounding primary visual cortex (V1, striate cortex) is significantly more elaborate than previously thought, consisting of about a dozen of interconnected, topographically organized extrastriate visual areas [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15] This knowledge, together with the availability of genetic and molecular tools, especially in mice, has triggered a surge of studies using rodents as models for advancing our understanding of cortical visual processing in mammals. While these and other studies have pointed out differences between rodents, carnivores, and primates [16, 22, 23], they highlight the usefulness of rodents as models in mammalian visual research
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.