Visual Neuroscience

Research Articles

Comparison of subcortical connections of inferior temporal and posterior parietal cortex in monkeys

Joan S. Baizera1, Robert Desimonea1 and Leslie G. Ungerleidera1

a1 Laboratory of Neuropsychology, National Institute of Mental Health, Bethesda

Abstract

To investigate the subcortical connections of the object vision and spatial vision cortical processing pathways, we injected the inferior temporal and posterior parietal cortex of six Rhesus monkeys with retrograde or anterograde tracers. The temporal injections included area TE on the lateral surface of the hemisphere and adjacent portions of area TEO. The parietal injections covered the posterior bank of the intraparietal sulcus, including areas VIP and LIP. Our results indicate that several structures project to both the temporal and parietal cortex, including the medial and lateral pulvinar, claustrum, and nucleus basalis. However, the cells in both the pulvinar and claustrum that project to the two systems are mainly located in different parts of those structures, as are the terminals which arise from the temporal and parietal cortex. Likewise, the projections from the temporal and parietal cortex to the caudate nucleus and putamen are largely segregated. Finally, we found projections to the pons and superior colliculus from parietal but not temporal cortex, whereas we found the lateral basal and medial basal nuclei of the amygdala to be reciprocally connected with temporal but not parietal cortex. Thus, the results show that, like the cortical connections of the two visual processing systems, the subcortical connections are remarkably segregated.

(Received February 02 1992)

(Accepted June 12 1992)

Correspondence:

p1 Present address of Joan S. Baizer: Department of Physiology, State University of New York at Buffalo, 4234 Ridge Lea Road, Amherst, NY 14226, USA.

Footnotes

Reprint requests to: Leslie G. Ungerleider, Laboratory of Neuropsychology, NIMH, Building 9, Room 1E104, Bethesda, MD 20892, USA.