Receptor-driven, multimodal mapping of cortical areas in the macaque monkey intraparietal sulcus

Abstract

<jats:p>The intraparietal sulcus (IPS) is structurally and functionally heterogeneous. We performed a quantitative cyto- and receptor architectonical analysis to provide a multimodal map of the macaque IPS. We identified 17 cortical areas, including novel areas PEipe, PEipi (external and internal subdivisions of PEip), and MIPd. Multivariate analyses of receptor densities resulted in a grouping of areas based on the degree of (dis)similarity of their receptor architecture: a cluster encompassing areas located in the posterior portion of the IPS and associated mainly with the processing of visual information, a cluster including areas found in the anterior portion of the IPS and involved in sensorimotor processing, and an 'intermediate' cluster of multimodal association areas. Thus, differences in cyto- and receptor architecture segregate the cortical ribbon within the IPS, and receptor fingerprints provide novel insights into the relationship between the structural and functional segregation of this brain region in the macaque monkey.</jats:p>

A dopamine gradient controls access to distributed working memory in monkey cortex

“…Receptor density at the synapse is the functionally important quantity, and is directly measured here. The map of D1 receptor density here greatly expands previous descriptions of D1 receptor densities (Goldman-Rakic et al 1990;Impieri et al 2019;Lidow et al 1991;Niu et al 2020;Richfield et al 1989). We show that D1 receptor density increases along the cortical hierarchy, peaking in prefrontal and posterior parietal cortex.…”

“…Collection of this data is underway and will be made available in future studies. With the exception of the receptor densities in the superior parietal lobe (Impieri et al 2019) and intraparietal sulcus (Niu et al 2020), all D1 receptor densities are reported for the first time in this study.…”

“…All anatomical data was mapped to the appropriate parcellations on the Yerkes19 surface. For the present study, we mapped all data to the 40 area Lyon subgraph Markov et al 2014b, as the areas in this parcellation were generally larger than those in the Jülich macaque atlas (Impieri et al, 2019;Niu et al, 2020;Rapan et al, In Prep;Niu et al, In prep; this paper) and the Queensland (spine count) injection sites (Elston 2007), and closer to standard areal descriptions than the Vanderbilt (neuronal density) (Collins et al 2010) sections.…”

“…Dopamine modulates neural activity through its receptors, of which the D1 receptor is the most common in cortex. The density of D1 receptors is known only for small sections of monkey cortex (Goldman-Rakic et al 1990;Impieri et al 2019;Lidow et al 1991;Niu et al 2020;Richfield et al 1989). A detailed map of the density of D1 receptors across cortex would clarify the degree to which dopamine's influence on cortical processing is restricted to specific sections of cortex, or distributed throughout cortical systems.…”

Functional links between sensory representations, choice activity, and sensorimotor associations in parietal cortex

“…Visually guided interactions with the environment require the creation of robust 3D object representations from ambiguous sensory signals and mapping of those representations to appropriate motor responses. In this study, we investigated the relationships between the robustness of 3D visual representations, choice-related activity, and motor-related activity in area CIP, a relatively understudied region of parietal cortex that was only recently confirmed to be an architectonically distinct brain region ( Katsuyama et al, 2010 ; Niu et al, 2020 ). Our findings revealed previously unrecognized links between the fidelity of high-level sensory representations, choice-related activity, and motor-related activity.…”