Cortical and subcortical afferent connections of the primate's temporal pole: A study of rhesus monkeys, squirrel monkeys, and marmosets

Abstract

The afferent connections of the primate's temporopolar cortex were investigated with the retrograde horseradish peroxidase technique. Old World and New World monkeys received small unilateral injections of horseradish peroxidase. These labeled cells in a number of cortical, thalamic, and brainstem regions and in a few further telencephalic and diencephalic regions. Cortically, the neighboring areas of the inferior and superior temporal gyrus and the insula contained a considerable number of labeled cells. Furthermore, a substantial projection arose from the orbitofrontal and the frontopolar cortex. The cingulate gyrus contained only very few labeled cells. Interhemispherically, corticocortical connections arose mainly from temporal lobe areas. Labeled cells were seen in various regions of the basal forebrain and cells labeled only faintly in the lateral and basal accessory nuclei of the amygdala. The claustrum contained labeled neurons only in one rhesus monkey. On the diencephalic level, the caudal medial portion of the medial pulvinar was the principal thalamic source of afferents to the temporopolar cortex. Furthermore, labeled cells were found in the neighboring, caudal part of the mediodorsal nucleus, within and along the nucleus limitans, in the medial geniculate nucleus, and in several nuclei of the nonspecific system. The fields of Forel, the zona incerta, and lateral and dorsomedial hypothalamic areas contained a few labeled cells. Within the brainstem of the rhesus monkeys those regions projecting diffusely to the cortex contained a few labeled neurons. Furthermore, these brains had some labeled cells in the regions of the nuclei medialis annuli aqueductus, tractus mesencephalicus nervi trigemini, and trochlearis. Although among the three species differences in the cortical and thalamic projection patterns were observed, the regions projecting most densely to the temporal pole were similar in principle. This statement holds in particular for cortical and thalamic sites. However, the greatest number of labeled cells was found in the rhesus monkey, a fact that cannot be attributed solely to the size of the horseradish peroxidase injections and the size of the brain, but that appears rather to represent a true species difference. From our results we conclude that the temporopolar cortex constitutes a cortical area necessary for effective affectional-sensory integration.

Thalamic Connections of Auditory Cortex in Marmoset Monkeys: Lateral Belt and Parabelt Regions

“…The concentration of cells in PM was mainly in the medial portion, which has been associated with auditory cortex Jacobson, 1975, 1976;Romanski et al, 1997;Hackett et al, 1998b). The strong connections between PM and the parabelt are consistent with the position of the parabelt as a later stage in the hierarchy of auditory cortex (Hackett, 2011) as often claimed for higher order areas which receive strong pulvinar inputs (DeVito and Simmons, 1976;Markowitsch et al, 1985;Yeterian and Pandya, 1989;Schmamann and Pandya, 1990;Cusick et al, 1993). The strong links between the pulvinar and parabelt may also indicate that the parabelt is involved in the proposed corticothalamocortical (CTC) circuits that serve to relay information between cortical areas (Sherman and Guillery, 2001;Guillery and Sherman, 2002;Sherman and Guillery, 2002;Sherman, 2007).…”

A role for left temporal pole in the retrieval of words for unique entities

“…Other lesion studies implicate the left anterior thalamus [Cohen et al, 1994, Moreaud et al, 1995Semenza and Zettin, 1988;Luchelli and De Renzi, 1992]. Tracer studies in nonhuman primates have identified parts of the medial dorsal and pulvinar nuclei as connected to BA 38 [Trojanowski and Jacobson, 1974;Markowitsch et al, 1985;Gower, 1989]. It is possible that the lesions in those studies affected the interaction of anterior temporal cortex with thalamic nuclei.…”

Cerebral Representation of One’s Own Past: Neural Networks Involved in Autobiographical Memory

“…Additional support to this hypothesis is provided by clinical observations of retrograde amnesia in patients with combined damage of anterolateral temporal areas and prefrontal areas (Markowitsch, 1995b), suggesting that the prefrontal cortex acts as a kind of control center for effortful initiation of recall (Jetter et al, 1986) and the sequencing and organizing of information (Milner et al, 1985;Goldman-Rakic and Friedman, 1991;Stuss et al, 1994;GoldmanRakic, 1995). This, together with the anterolateral temporal cortex which provides a connecting link to posterior cortical centers of integration as the major storage places of engrams (Markowitsch et al, 1985), implies an important role of the prefrontal cortex in the initiation of directed ecphory. The results on prefrontal activation obtained in the present study are in good agreement with the above ideas, because the prefrontal cortex is activated during the ecphory of autobiographical memory retrieval.…”