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The morphology and distribution of striate cortex terminals in the inferior and lateral subdivision of the Macaca monkey pulvinar
Author(s) -
Ogren Marilee P.,
Hendrickson Anita E.
Publication year - 1979
Publication title -
journal of comparative neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.855
H-Index - 209
eISSN - 1096-9861
pISSN - 0021-9967
DOI - 10.1002/cne.901880113
Subject(s) - superior colliculus , neuroscience , biology , visual cortex , thalamus , superior colliculi , axon , retinotopy , anatomy , cortex (anatomy) , cerebral cortex , visual system
The origin of the various types of axon terminals in Macaca pulvinar remains uncertain because of the contradictory results obtained in EM degeneration studies. We have used EM‐autoradiography to determine the morphology of terminals in the inferior and lateral pulvinar which originate from neurons in visual cortex. After injections of H 3 proline into area 17, both the small diameter (RS) and the large diameter (RL) terminals containing round vesicles and making asymmetric contacts are labeled in the two pulvinar subdivisions. Labeled and unlabeled terminals are intermixed within the pulvinar focus which suggests that the dendrites of the same pulvinar neuron receive overlapping inputs from several cortical areas. Because only 5% of the pulvinar terminals are RLs (Ogren and Hendrickson, '79), and this small number of RLs originates from at least two visual cortical areas plus the superior colliculus (Partlow et al., '77), superior colliculus input to inferior pulvinar is small compared to the combined RS and RL cortical input. Together the findings from this study and the preceding paper (Ogren and Hendrickson, '79), show that while pulvinar is typical of other thalamic nuclei in the structure of its neurons and synapses, it differs in that the input from subcortical structures is minimal. It is suggested that inferior and lateral pulvinar function principally as integrators of visual cortical information.