The interest of science, and particularly of the fields of biology and neuroscience, is in understanding the functioning of the nervous system in relation to the products of brain activity, such as cognition and behavior, has led to the development of several investigations that put their focus of study in the frontal lobes, especially in the prefrontal regions. The dorsolateral, medial and orbito prefrontal cortex have been functionally studied; however, the anatomical projections of the axons and the description of the neural networks that originate in these areas of the brain have brought more interest in some than in others. With that being said, the medial region of the prefrontal lobes have not received sufficient attention in the approach and detail of its projections and relations with the subcortical structures of the brain, among which the tonsils and hippocampus are noted for having a functional relationship when considering the manifestations clinics of neurological and neuropsychological syndromes resulting from medial prefrontal cortex damage. Therefore, this research proposal is aimed to establish the neuroanatomic substrate of the cognitive and visceral-motor circuits of the prelimbic and infralimbic cortex of the medial prefrontal cortex and their projections and interactions with subcortical complexes in Callithrix Jacchus primate; delimited to areas and nucleus of the diencephalic, amygdaloid and hippocampus complexes. The research developed is presented as a comparative descriptive study, with non-probabilistic sampling, considering the use of the primate as an animal study model, of the species Callithrix Jacchus (known as Marmoset). As a technique to track nerve cells, the technique of axon marking, antegrade marking was used; deposited in the pre-limbic (PL) and infralimbic (IL) cortices. Among the planned hypotheses, it was proposed that there is an organized and exclusive distribution in the directionality of the fibers towards the subcortical regions associated with the three complexes of interest, in primates, a fact that was possible to corroborate from the results obtained. Most of the areas and nuclei of the diencephalic and amygdaloid complex received fibers of both cortices (PL and IL), and in the diencephalon, the four regions were reached from the PL, and the fibers of the IL were restricted to the thalamus and the epithalamus; in general, at different densities, but in the hippocampus complex the fibers were restricted to PL projections. It was also possible to determine the pattern of rostral-caudal distribution of the fibers in these areas, as well as to identify that the groups of fibers that come from the IL are more grouped within the complexes, than the groups that originate in the PL. These and other findings in this research stand out for their originality, as well as the pioneering methodological characteristics in achieving their objective; facts that, as a novelty, contribute to the study of the morphological correlates of the anatomical-functional activity in the brain.