Summary
We have analyzed the distributions of inter-hemispheric and striate-peristriate connections in the South American marsupial, Marmosa elegans (mouse opossum). Following multiple injections of horseradish peroxidase (HRP) into one hemisphere, we found that anterogradely labeled terminations and retrogradely labeled perikarya are distributed unevenly in the contralateral hemisphere, forming a distinct tangential pattern in striate and peristriate cortex. This pattern delineates as many as eight peristriate areas relatively poor in commissural connections in lateral peristriate cortex, and in lateral and anterolateral portions of peristriate cortex. Single injections of HRP conjugated with wheat germ agglutinin into anterior or posterior regions of striate cortex produced as many as nine discrete ipsilateral fields of labeled perikarya, and terminations distributed over a broad cortical area in lateral and anterolateral peristriate cortex. Our observations of multiple areas with little or no HRP labeling in the interhemisferic pattern, and of multiple ipsilateral striate projection fields, indicate that the topography of visual cortex in Marmosa is highly elaborate, and suggest that extrastriate cortex is subdivided into several visual areas. Furthermore, by showing that the organization of visual cortex in this marsupial is as complex as in many placental mammals, our data support the view that a basic cortical plan, consisting of multiple visual areas, appeared early in mammalian evolution.
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References
Benevento LA, Ebner FF (1971) The areas and layers of cortico cortical terminations in the visual cortex of the Virginia opossum. J Comp Neurol 141:157–190
Bravo H, Olavarria J, Torrealba F (1990) Comparative study of visual inter and intrahemispheric cortico-cortical connections in five native Chilean rodents Anat Embryol 181:67–73
Cabana T, Martin GF (1985) The development of commissural connections in somatic motor-sensory areas of neocortex in the North American opossum. Anat Embryol 171:121–128
Coleman J, Clerici WJ (1981) Organization of thalamic projections to visual cortex in Opossum. Brain Behav Evol 18:41–59
Crewther DP, Crewther SG, Sanderson KJ (1984) Primary visual cortex in the brushtailed possum: receptive field properties and corticocortical connections. Brain Behav Evol 24:184–197
Cusick CG, MacAvoy MG, Kaas JH (1985) Interhemispheric connections of cortical sensory areas in tree shrews. J Comp Neurol 235:111–128
Ebner FF (1967) Afferent connections to Neocortex in the opossum (Didelphis virginiana). J Comp Neurol 129:241–268
Granger CG, Masterton RB, Glendenning KK (1985) Origins of interhemispheric fibers in acallosal opossum (with comparison to callosal origins in rat). J Comp Neurol 241:82–98
Gibson AR, Hansma DI, Houk JC, Robison FR (1984) A sensitive low artifact TMB procedure for demonstration of WGA-HRP in the CNS. Brain Res 298:235–241
Gray PA (1924) The cortical lamination pattern of the opossum (Didelphis virginiana). J Comp Neurol 37:221–263
Heath CJ, Jones EG (1971) Interhemispheric pathways in the absence of corpus callosum. J Anat 109:253–270
Hess DT, Merker BH (1983) Technical modification of the Gallyas silver stain for myelin. J Neurosci Methods 8:95–97
Martinich S, Bravo H (1987) Estudio de las proyecciones comisurales visuales en el marsupial Marmosa elegans. VIII Congreso, Asociación Panamericana de Anatomía, Santiago Chile, Res 70
Montero VM, Rojas A, Torrealba F (1973a) Retinotopic organization of striate and peristriate visual cortex in the albino rat. Brain Res 53:197–201
Montero VM, Bravo H, Fernández V (1973b) Striate-peristriate cortico-cortical connections in the albino and gray rat. Brain Res 53:202–207
Olavarria J, Montero VM (1984) Relation of callosal and striate-extrastriate cortical connections in the rat: morphological definition of extrastriate visual areas. Exp Brain Res 54:240–252
Olavarria J, Montero VM (1989) Organization of visual cortex in the mouse revealed by correlating callosal and striate-extrastriate connections. Visual Neurosci 3:59–69
Olavarria J, Montero VM (1990) Elaborate organization of visual cortex in the hamster. Neurosci Res 8:40–47
Olavarria J, Van Sluyters RC (1983) Widespread callosal connections in infragranular visual cortex of the rat. Brain Res 279:233–237
Olavarria J, Van Sluyters RC (1984) Callosal connections of the posterior neocortex in normal-eyed, congenitally anophthalmic, and neonatally enucleated mice. J Comp Neurol 230:249–268
Sanderson IT (1955) Mammals of the world. Hamish Hamilton, London
Sesma MA, Casagrande VA, Kaas JH (1984) Cortical connections of area 17 in tree shrews. J Comp Neurol 230:337–351
Sousa APB, Gattass R, Oswaldo-Cruz E (1978) The projection of the opossum's visual field on the cerebral cortex. J Comp Neurol 177:569–588
Simpson GG (1970) South American mammals. Chilton Books
Thomas HC, Espinosa SG (1987) Relationship between interhemispheric cortical connections and visual areas in hooded rats. Brain Res 417:214–224
Van Essen DC, Zeki SM (1978) The topographic of the rhesus monkey prestriate cortex. J Physiol (Lond) 277:193–226
Whitteridge (1965) Area 18 and the vertical meridian of vision. In: Etlingen EG (ed) CIBA Studies group 20, Functions of corpus callosum. Churchill, London
Zeki SM (1977) Simultaneous anatomical demonstration of the representation of the vertical and horizontal meridian in areas V2 and V3 of rhesus monkey visual cortex. Proc R Soc Lond [Biol] 195:517–523
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Bravo, H., Olavarría, J. & Martinich, S. Patterns of interhemispheric and striate-peristriate connections in visual cortex of the South American marsupial Marmosa elegans (mouse opossum). Anat Embryol 182, 583–589 (1990). https://doi.org/10.1007/BF00186465
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DOI: https://doi.org/10.1007/BF00186465