Topographic organization of connections between the hypothalamus and prefrontal cortex in the rhesus monkey
Article first published online: 6 DEC 1998
Copyright © 1998 Wiley-Liss, Inc.
Journal of Comparative Neurology
Volume 398, Issue 3, pages 393–419, 31 August 1998
How to Cite
Rempel-Clower, N.L. and Barbas, H. (1998), Topographic organization of connections between the hypothalamus and prefrontal cortex in the rhesus monkey. J. Comp. Neurol., 398: 393–419. doi: 10.1002/(SICI)1096-9861(19980831)398:3<393::AID-CNE7>3.0.CO;2-V
- Issue published online: 6 DEC 1998
- Article first published online: 6 DEC 1998
- Manuscript Accepted: 4 MAY 1998
- Manuscript Revised: 20 MAR 1998
- Manuscript Received: 22 AUG 1997
- National Institutes of Health. Grant Number: NS24760
- National Institute of Mental Health. Grant Number: F32 MH11151
- medial prefrontal
Prefrontal cortices have been implicated in autonomic function, but their role in this activity is not well understood. Orbital and medial prefrontal cortices receive input from cortical and subcortical structures associated with emotions. Thus, the prefrontal cortex may be an essential link for autonomic responses driven by emotions. Classic studies have demonstrated the existence of projections between prefrontal cortex and the hypothalamus, a central autonomic structure, but the topographic organization of these connections in the monkey has not been clearly established. We investigated the organization of bidirectional connections between these areas in the rhesus monkey by using tracer injections in orbital, medial, and lateral prefrontal areas. All prefrontal areas investigated received projections from the hypothalamus, originating mainly in the posterior hypothalamus. Differences in the topography of hypothalamic projection neurons were related to both the location and type of the target cortical area. Injections in lateral eulaminate prefrontal areas primarily labeled neurons in the posterior hypothalamus that were equally distributed in the lateral and medial hypothalamus. In contrast, injections in orbitofrontal and medial limbic cortices labeled neurons in the anterior and tuberal regions of the hypothalamus and in the posterior region. Projection neurons targeting orbital limbic cortices were more prevalent in the lateral part of the hypothalamus, whereas those targeting medial limbic cortices were more prevalent in the medial hypothalamus. In comparison to the ascending projections, descending projections from prefrontal cortex to the hypothalamus were highly specific, originating mostly from orbital and medial prefrontal cortices. The ascending and descending connections overlapped in the hypothalamus in areas that have autonomic functions. These results suggest that specific orbitofrontal and medial prefrontal areas exert a direct influence on the hypothalamus and may be important for the autonomic responses evoked by complex emotional situations. J. Comp. Neurol. 398:393–419, 1998. © 1998 Wiley-Liss, Inc.