The Second Visual System of The Tree Shrew

• Published in: Journal of comparative neurology (1911) Vol. 527; no. 3; pp. 679 - 693
• Main Authors: Petry, Heywood M., Bickford, Martha E.
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 15.02.2019
• Subjects: Flight simulation; Historical account; Lateral geniculate nucleus; Pulvinar; Retina; striate cortex; Superior colliculus; temporal cortex; Thalamus; Tupaia; Visual cortex; Visual pathways; Visual system; striate cortex; pulvinar; temporal cortex; Tupaia; superior colliculus; thalamus
• ISSN: 0021-9967; 1096-9861
• DOI: 10.1002/cne.24413

This review provides a historical account of the discovery of secondary visual pathways (from retina to the superior colliculus to the dorsal thalamus and extrastriate cortex), and Vivien Casagrande's pioneering studies of this system using the tree shrew as a model. Subsequent studies of visual pathways in the tree shrew are also reviewed, beginning with a description of the organization and central projections of the tree shrew retina. The organization and connectivity of second visual system components that include the retino‐recipient superior colliculus, tecto‐recipient pulvinar nucleus and its projections, and the tecto‐recipient dorsal lateral geniculate nucleus and its projections are detailed. Potential functions of the second visual system are discussed in the context of this work and in the context of the behavioral studies that initially inspired the secondary visual system concept. This review provides a historical account of the discovery of secondary visual pathways (from retina to the superior colliculus to the dorsal thalamus and extrastriate cortex), and Vivien Casagrande's pioneering studies of this system using the tree shrew as a model. The organization and connectivity of second visual system components are detailed. Potential functions of the second visual system also are discussed in the context of this work and in the context of the behavioral studies that initially inspired the second visual system concept.