Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Direct visual input to the limbic system: Crossed retinal projections to the nucleus anterodorsalis thalami in the tree shrew

  • 85 Accesses

  • 65 Citations


Evidence for a direct projection from the retina to the nucleus anterodorsalis thalami in the insectivore, Tupaia glis, is presented. 100 μCi tritiated amino acid or amino acid/monosaccharide cocktail were administered as two separate intravitreal injections of 50 μCi each. Fibers were traced using thawmount autoradiography in which tissue is frozen in liquid propane, cryostat-cut, and mounted on photographic emulsion precoated slides (Conrad and Stumpf, 1974). From the dorsolateral geniculate body, contralateral retinal fibers continue as a dorsomedial extension of the optic tract. When traced rostrally from this point, the fibers form a thin fascicle coursing medially under the third ventricle. In the anterior thalamus the bundle arborizes within the n. anterodorsalis, infiltrating its caudal pole completely but only encapsulating the nucleus anteriorly.

This new retino-anterodorsal thalamic projection, together with the known anterior thalamic-retrosplenial projection, represents a third visual pathway in Tupaia glis distinct from the retino-geniculo-striatal and retino-tecto-pulvinarperistriatal systems. It is significant that each of these thalamic relay nuclei projects to an architectonically different cortical region, with the nucleus anterodorsalis sending afferents to the phylogenetically most primitive of the visual cortices, the retrosplenial proisocortex or prostriata (Vitzthum and Sanides, 1967). It is proposed that the retino-anterior thalamic-retrosplenial circuit forms an anatomical substrate by which light cues may affect emotional behavior and corresponding neurovisceral responses.

This is a preview of subscription content, log in to check access.


  1. Conrad, C.D., Stumpf, W.E.: Retinal projections traced with thaw-mount autoradiography and multiple injections of tritiated precursor or precursor cocktail. Cell Tiss. Res. 155, 283–290 (1974)

  2. Conrad, C.D., Stumpf, W.E.: Endocrine-optic pathways to the hypothalamus. In: Anatomical Neuroendocrinology. (W. E. Stumpf and L.D. Grant, Eds.). New York: Karger (in press), 1975)

  3. Domesick, V.B.: Thalamic relationships of the medial cortex in the rat. Brain Behav. Evol. 6, 457–483 (1972)

  4. Ebbesson, S.O.E.: On the organization of central visual pathways in vertebrates. Brain Behav. Evol. 3, 178–194 (1970)

  5. Gergen, J.A., MacLean, P.D.: The limbic system: photic activation of limbic cortical areas in the squirrel monkey. Ann. N. Y. Acad. Sci. 117, 69–87 (1964)

  6. Guillery, R.W.: Degeneration in the hypothalamic connexions of the albino rat. J. Anat. (Lond.) 91, 91–115 (1957)

  7. LeGros Clark, W.E.: Studies on the optic thalamus of the insectivora — the anterior nuclei. Brain 52, 334–358 (1929)

  8. MacLean, P.D.: The limbic and visual cortex in phylogeny: further insights from anatomic and microelectrode studies. In: Evolution of the Forebrain: Phylogenesis and Ontogenesis of the Forebrain. (R. Hassler and H. Stephan, Eds.), pp. 443–453. New York: Plenum Press 1967

  9. MacLean, P.D., Creswell, G.: Anatomical connections of the visual system with limbic cortex of monkey. J. comp. Neurol. 138, 265–278 (1970)

  10. MacLean, P.D., Yokuta, T., Kinnard, M.A.: Photically sustained on responses of units in posterior hippocampal gyrus of awake monkey. J. Neurophysiol. 31, 870–883 (1968)

  11. O'Leary, J.L., Bishop, G.H.: Margins of the optically excitable cortex in the rabbit. Arch. Neurol. Psychiat. (Chic.) 40, 482–499 (1938)

  12. Pandya, D.N., Sanides, F.: Architectonic parcellation of the temporal operculum in Rhesus monkey and its projection pattern. Z. Anat. Entwickl.-Gesch. 139, 127–161 (1973)

  13. Papez, J.W.: A proposed mechanism of emotion. Arch. Neurol. Psychiat. (Chic.) 38, 725–743 (1937)

  14. Rose, J.E., Woolsey, C.N.: Structure and relations of limbic cortex and anterior thalamic nuclei in rabbit and cat. J. comp. Neurol. 89, 279–347 (1948)

  15. Snyder, M., Diamond, I.T.: The organization of the visual cortex in the tree shrew. Brain Behav. Evol. 1, 244–288 (1968)

  16. Thompson, J.M., Woolsey, C.N., Talbot, S.A.: Visual areas I and II of cerebral cortex of rabbit. J. Neurophysiol. 13, 277–288 (1950)

  17. Vitzthum, H.G., Sanides, F.: Entwicklungsprinzipien der menschlichen Sehrinde. In: Evolution of the Forebrain. (R. Hassler and H. Stephan, Eds.), pp. 435–442. New York: Plenum Press 1967

Download references

Author information

Additional information

Supported by NICHHD grant HD-03110 to the Biological Sciences Research Center of the Child Development Institute; by NIMH grant 11107 and a grant from the Alfred P. Sloan Foundation to the Neurobiology Program; and by US PHS grant 09914 to W.E.S.

Predoctoral Trainee in Neurobiology.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Conrad, C.D., Stumpf, W.E. Direct visual input to the limbic system: Crossed retinal projections to the nucleus anterodorsalis thalami in the tree shrew. Exp Brain Res 23, 141–149 (1975). https://doi.org/10.1007/BF00235456

Download citation

Key words

  • Retinal projections
  • Anterior thalamus (nucleus anterodorsalis)
  • Limbic system
  • Visual system
  • Autoradiography (radioautography)