Morphological patterns of the intraparietal sulcus and the anterior intermediate parietal sulcus of Jensen in the human brain

Abstract

Distinct parts of the intraparietal sulcal cortex contribute to sensorimotor integration and visual spatial attentional processing. A detailed examination of the morphological relations of the different segments of the complex intraparietal sulcal region in the human brain in standard stereotaxic space, which is a prerequisite for detailed structure-to-function studies, is not available. This study examined the intraparietal sulcus (IPS) and the related sulcus of Jensen in magnetic resonance imaging brain volumes registered in the Montreal Neurological Institute stereotaxic space. It was demonstrated that the IPS is divided into two branches: the anterior ramus and the posterior ramus of the IPS, often separated by a submerged gyral passage. The sulcus of Jensen emerges between the anterior and posterior rami of the IPS, and its ventral end is positioned between the first and second caudal branches of the superior temporal sulcus. In a small number of brains, the sulcus of Jensen may merge superficially with the first caudal branch of the superior temporal sulcus. The above morphological findings are discussed in relation to previously reported functional neuroimaging findings and provide the basis for future exploration of structure-to-function relations in the posterior parietal region of individual subjects.

Structural and functional integration between dorsal and ventral language streams as revealed by blunt dissection and direct electrical stimulation

“…In fact, microdissections showed a prevalent horizontal U-fibers orientation between SMG and AG due to the vertical sulcal organization of this region, including the supramarginal sulcus and the first, second, and third caudal branches of the STS (respectively, cSTS1, cSTS2, cSTS3) [Zlatkina and Petrides, 2014]. Particularly, the horizontal U-fibers underlying the cSTS1, which constitute a real elongation of the STS within the IPL, provide a unique and direct connection between the SMG/AG and the posterior thirds of STG and MTG (Fig.…”

Specifying the brain anatomy underlying temporo-parietal junction activations for theory of mind: A review using probabilistic atlases from different imaging modalities

“…Another issue we address is that TPJ shows high interindividual variability in macroanatomy [e.g., Segal and Petrides, 2012;Zlatkina and Petrides, 2014], which is characteristic for multimodal association areas of the cortex [Van Essen, 2005]. This could obscure an accurate anatomical characterization of functional activations found in the area.…”

Human Paleoneurology and the Evolution of the Parietal Cortex

“…The homology between humans and nonhuman primates for their parietal cortex is not clear, although the complexity of the intraparietal sulcus in H. sapiens may have displaced and repositioned internal and external folding regions, generating a lack of correspondence between human and nonhuman cortical topology [Zlatkina and Petrides, 2014]. It must be taken into account that most inferences are based on comparisons between humans and macaques, two lineages that are not closely related in terms of phylogeny, and that underwent separation and independent evolution for some 20 million years.…”