Cytoarchitectonic segregation of human posterior intraparietal and adjacent parieto-occipital sulcus and its relation to visuomotor and cognitive functions

Abstract

Human posterior intraparietal sulcus (pIPS) and adjacent posterior wall of parieto-occipital sulcus (POS) are functionally diverse, serving higher motor, visual and cognitive functions. Its microstructural basis, though, is still largely unknown. A similar or even more pronounced architectonical complexity, as described in monkeys, could be assumed. We cytoarchitectonically mapped the pIPS/POS in 10 human postmortem brains using an observer-independent, quantitative parcellation. 3D-probability maps were generated within MNI reference space and used for functional decoding and meta-analytic coactivation modeling based on the BrainMap database to decode the general structural–functional organization of the areas. Seven cytoarchitectonically distinct areas were identified: five within human pIPS, three on its lateral (hIP4-6) and two on its medial wall (hIP7-8); and two (hPO1, hOc6) in POS. Mediocaudal areas (hIP7, hPO1) were predominantly involved in visual processing, whereas laterorostral areas (hIP4-6, 8) were associated with higher cognitive functions, e.g. counting. This shift was mirrored by systematic changes in connectivity, from temporo-occipital to premotor and prefrontal cortex, and in cytoarchitecture, from prominent Layer IIIc pyramidal cells to homogeneous neuronal distribution. This architectonical mosaic within human pIPS/POS represents a structural basis of its functional and connectional heterogeneity. The new 3D-maps of the areas enable dedicated assessments of structure–function relationships.

Neural representations of own-voice in the human auditory cortex

“…Moreover, the left angular gyrus has the enhanced connectivity with the cerebellum and motor and pre-motor cortical regions, including the supplementary motor area, the pre-central gyrus, and the middle and superior frontal gyri 62 . This parieto-premotor cortical network is involved in the control of attention 63 and in visual 64 , 65 , auditory 66 , and cross-modal 67 , 68 processing. Thus it is possible that this network acts to direct attention simultaneously to the voice that closely resembles the own-voice.…”

Corticocortical Systems Underlying High-Order Motor Control

“…These encode actions of different complexity, from reaching and grasping to object manipulation and construction, tool use, oculomotor control, visuospatial attention, performance monitoring, as well as ethologically relevant functions underlying defensive behavior, and perform action observation-execution matching, as in the case of the mirror system. Parietofrontal streams can hardly be considered private routes devoted to just one function; rather, they are informationprocessing lines used for multiple purposes (Battaglia-Mayer and Caminiti, 2018;Borra and Luppino, 2018), as suggested by the multiplicity and functional heterogeneity of neural ensembles (Daitch and Parvizi, 2018) that they connect and by the complex organization of the intraparietal sulcus and parieto-occipital cortex in humans (Richter et al, 2019).…”

Cytoarchitectonic Characterization and Functional Decoding of Four New Areas in the Human Lateral Orbitofrontal Cortex

“…The present study provides a comprehensive cytoarchitectonic analysis of the human lateral OFC using a computerized approach to detect cytoarchitectonic borders between adjacent areas based on image analysis and statistical criteria (Schleicher et al, 1998(Schleicher et al, , 1999(Schleicher et al, , 2005, and provides cytoarchitectonic probabilistic maps in 3D reference space (Amunts and Zilles, 2015). The maps have been created based on the same methods as used for previous mapping studies of our group [most recent include, e.g., the parietal cortex (Richter et al, 2019), the motor cortex (Ruan et al, 2018), and the fusiform gyrus (Lorenz et al, 2017)], and allow to integrate them into a coherent atlas framework of the human brain. Meta-analytic connectivity modeling (MACM) was conducted to assess all task-based functional connectivities between the lateral OFC areas and their respective co-activated FIGURE 1 | Area 47 in the lateral orbitofrontal cortex (lateral OFC) in the human brain according to previous cytoarchitectonical analyses (Brodmann, 1909;von Economo and Koskinas, 1925;Von Economo, 1929;Öngür et al, 2003).…”