title: Organization of the human inferior parietal lobule based on receptor architectonics.
abstract: Human inferior parietal lobule (IPL) plays a key role in various cognitive functions. Its functional diversity, including attention, language, and action processing, is reflected by its structural segregation into 7 cytoarchitectonically distinct areas, each with characteristic connectivity patterns. We hypothesized that commonalities of the cytoarchitectonic, connectional, and functional diversity of the IPL should be reflected by a correlated transmitter receptor-based organization. Since the function of a cortical area requires a well-tuned receptor balance, the densities of 15 different receptors were measured in each IPL area. A hierarchical cluster analysis of the receptor balance revealed a tripartite segregation of the IPL into a rostral, middle, and caudal group. Comparison with other cortical areas showed strong similarities with Broca's region for all 3 groups, with the superior parietal cortex for the middle, and with extrastriate visual areas for the caudal group. Notably, caudal-most area PGp has a receptor fingerprint very similar to that of ventral extrastriate visual cortex. We therefore propose a new organizational model of the human IPL, consisting of 3 clusters, which corresponds to its known cytoarchitectonic, connectional, and functional diversity at the molecular level. This might reflect a general organizational principle of human IPL, beyond specific functional domains.
authors.affiliation: Institute of Neuroscience and Medicine (INM-1, INM-2), Research Centre Jülich, 52425 Jülich, Germany. s.caspers@fz-juelich.de
authors.forename: Svenja
authors.initials: S
authors.lastname: Caspers
authors.forename: Axel
authors.initials: A
authors.lastname: Schleicher
authors.forename: Mareike
authors.initials: M
authors.lastname: Bacha-Trams
authors.forename: Nicola
authors.initials: N
authors.lastname: Palomero-Gallagher
authors.forename: Katrin
authors.initials: K
authors.lastname: Amunts
authors.forename: Karl
authors.initials: K
authors.lastname: Zilles
mesh_terms: D000368:Aged; D001345:Autoradiography; D001931:Brain Mapping; D016000:Cluster Analysis; D005260:Female; D006801:Humans; D008297:Male; D010296:Parietal Lobe / Q000378:metabolism*; D017981:Receptors, Neurotransmitter / Q000032:analysis* / Q000096:biosynthesis*
chemical_list: D017981:Receptors, Neurotransmitter