Differential Connections of the Temporal Pole with the Orbital and Medial Prefrontal Networks in Macaque Monkeys HIDEKI KONDO, KADHARBATCHA S. SALEEM, AND JOSEPH L. PRICE * Department of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, Missouri 63110 ABSTRACT Previous studies indicate that the orbital and medial prefrontal cortex (OMPFC) is organized into “orbital” and “medial” networks, which have distinct connections with cortical, limbic, and subcortical structures. In this study, retrograde and anterograde tracer experi- ments in monkeys demonstrated differential connections between the medial and orbital networks and the dorsal and ventral parts of the temporal pole. The dorsal part, including dysgranular and granular areas (TGdd and TGdg), is reciprocally connected with the medial network areas on the medial wall and gyrus rectus (areas 10m, 10o, 11m, 13a, 14c, 14r, 25, and 32) and on the lateral orbital surface (areas Iai and 12o). The strongest connections are with areas 10m (caudal part), 14c, 14r, 25, 32, and Iai. The agranular temporal pole (TGa) is connected with several areas, but most strongly with medial network area 25. The granular area around the superior temporal sulcus (TGsts) and the ventral dysgranular and granular areas (TGvd and TGvg) are reciprocally connected with the orbital network (especially areas 11l, 13b, 13l, 13m, Ial, Iam, and Iapm). TGsts is strongly connected with the entire orbital network, whereas areas TGvd and TGvg have lighter and more limited connections. Intrinsic connections within the temporal pole are also restricted to dorsal or ventral parts. Together with evidence that the dorsal and ventral temporal pole are differentially connected to auditory and visual areas of the superior and inferior temporal cortex, the results indicate separate connections between these systems and the medial and orbital prefrontal networks. J. Comp. Neurol. 465:499 –523, 2003. © 2003 Wiley-Liss, Inc. Indexing terms: orbital cortex; medial prefrontal cortex; temporal cortex; anterograde axonal tracers; retrograde axonal tracers; architectonic areas Recent anatomical studies of the orbital and medial prefrontal cortex (OMPFC) in monkeys defined two dis- tinct prefrontal networks, an “orbital network,” which con- sists of most of the areas on the orbital surface, and a “medial network,” which consists of areas on the medial wall and a few areas on the orbital surface. The two networks were defined from an analysis of corticocortical connections within the OMPFC (Carmichael and Price, 1996), but they also have distinct connections with other cortical, limbic, and subcortical areas (Ray and Price, 1993; Carmichael and Price, 1995a,b; An et al., 1998; O ¨ ngu ¨ r et al., 1998; Ferry et al., 2000; O ¨ ngu ¨ r and Price, 2000). The orbital network receives several sensory inputs from visual, somatosensory, olfactory, and gustatory cor- tical areas (Carmichael et al., 1994; Carmichael and Price, 1995b). It appears to be involved in analysis of sensory stimuli related to food and reward (Rolls, 2000). The me- dial network receives few of these sensory inputs (Car- michael and Price, 1995b) but sends outputs to the hypo- thalamus (O ¨ ngu ¨ r et al., 1998) and the periaqueductal gray (An et al., 1998). It has been considered to be a viscero- motor or emotomotor system (O ¨ ngu ¨ r and Price, 2000). In Grant sponsor: National Institutes of Health; Grant number: DC000093. *Correspondence to: Joseph L. Price. Department of Anatomy & Neuro- biology, Campus Box 8108, Washington University School of Medcine, 660 S. Euclid Avenue, St. Louis, MO 63110. E-mail: pricej@pcg.wustl.edu Received 21 March 2003; Revised 19 May 2003; Accepted 20 May 2003 DOI 10.1002/cne.10842 Published online the week of September 8, 2003 in Wiley InterScience (www.interscience.wiley.com). THE JOURNAL OF COMPARATIVE NEUROLOGY 465:499 –523 (2003) © 2003 WILEY-LISS, INC.