Friday, Jun 27: 1:00 PM - 2:00 PM
1366
Roundtable
Brisbane Convention & Exhibition Centre
Room: M2 (Mezzanine Level)
Recent articles from Noble et al. and Petersen et al. have voiced opposing opinions on the question of whether the mapping of cortical areas should remain a goal of neuroimaging investigations of brain function. Noble et al. state that cortical organization is multidimensional and dynamic and that focusing on cortical areas may limit computational models of function. Petersen et al. state that the cortical area remains a fundamental unit of cortical organization that should strongly constrain any computational models of function. These strongly held views influence both the types of analyses that current studies will utilize as well as the characteristics of future large neuroimaging studies such as the ABCD and HCP projects.
In this roundtable we will host a discussion of these viewpoints with the goal of reconciliation. The panel will include the senior authors of both opinion pieces as well as perspectives from other human and non-human primate researchers. Dustin Scheinost will present the perspective in Noble et al., and Evan Gordon will present the perspective in Petersen et al. Nicola Palomero-Gallagher will discuss the cortical distribution of receptors in relation to cytoarchitectonic organization, Sarah Heilbronner will discuss the levels of cortical organization from microscopic to macroscopic, and Ting Xu will discuss the principles of macroscopic brain organization. Gaurav Patel and Avram Holmes will provide introduction and moderate.
Audience members will learn differing perspectives on the principles of cortical organization, how these principles may apply to their own studies, and how compatible these perspectives are.
1: What are the principles used to define a cortical area?
2: What are the similarities and differences in the localization and anti-localization schools of thought?
3: What are the potential units of cortical organization from microscopic to macroscopic?
The target audience for this roundtable discussion would people who use anatomical and functional imaging techniques to exam brain functioning and brain-behavior relationships, whether in neurotypical or clinical populations.
Presentations
Human neuroscience research remains largely preoccupied with mapping distinct brain areas to complex psychological processes and features of mental health disorders. While this reductionist and localizationist perspective has resulted in several substantive contributions to the field, it has long been viewed as only a piece of the puzzle. Emerging evidence now empirically demonstrates how a historical reliance on localizationist techniques may underlie recent challenges to reproducibility and translation in human neuroscience. To advance discovery, we must collectively better incorporate complex systems and machine-learning approaches that better capture the multidimensional, dynamic, and interacting nature of the brain. Moreover, we must begin to contend with how to best integrate complementary modalities beyond the brain to better understand complex mental processes.
Cortical organization should constrain the study of how the brain performs behavior and cognition. A fundamental concept in cortical organization is that of arealization: that the cortex is parceled into discrete areas. I will discuss how principles of cortical arealization apply to neuroimaging research, and I will highlight examples of these principles using high-data “precision” neuroimaging in single individuals. I will further discuss how some interpretations of neuroimaging observations require assumptions that violate the principles of arealization. I will close by articulating how principles of neurobiology should strongly guide the nature of computational explanations.
Presenter
Evan Gordon, Ph.D., Washington University School of Medicine
Radiology
St. Louis, MO
United States
Drawing on studies of the human and macaque cortex, I will discuss how the analysis of receptor distribution patterns serves to link structural and functional segregation patterns of the brain. Simultaneous examination of the distribution of cell bodies and multiple receptor types in the human and macaque brain has shown that changes in receptor density are indicative of boundaries between areas, and that changes in receptor architecture occur at positions comparable to those of cytoarchitectonic borders. What makes this multimodal approach particularly powerful is that not all receptors delineate every possible cytoarchitectonic boundary. Thus, each neurotransmitter receptor reveals larger or smaller 'families' of cytoarchitectonically distinct but neurochemically related areas. Importantly, similarities between areas in their specific co-distribution patterns of multiple receptors, i.e., their receptor fingerprint, constitute the molecular basis for communication between these areas. It is these similarities that give brain areas the ability to form a network that supports a specific functional system. Furthermore, receptor fingerprints also reveal hierarchical processing levels and segregate cortical types. Thus, receptor fingerprints enable the analysis of both the structural segregation of the brain and its functional connectivity principles.
The anatomical parcellation of the cerebral cortex into brain areas is foundational to cognitive and systems neuroscience. I will critically explore the neuroanatomical foundations of areal parcellation, incorporating cytoarchitecture, connectivity, and transcriptomics. I argue that the brain area, as it is generally understood, is just one of several equally important organizing principles of the cerebral cortex. Other organizations include macroscale gradients, distributed networks, layers, and patchy and columnar structures at multiple scales.
Recent debates in neuroscience highlight differing perspectives on cortical organization, particularly the roles of discrete arealization and continuous gradients in understanding brain organization. Traditional approaches emphasize distinct cortical areas as fundamental units of organization. However, emerging evidence suggests that cortical organization may also reflect large-scale, multidimensional gradients that span the brain, capturing continuous aspects of functional connectivity. Studies in humans and nonhuman primates reveal organizational principles that may blend these frameworks, with functional axes emerging at the macroscale while finer-scale analyses uncover localized areas. I will explore empirical evidence from comparative studies that illustrate how large-scale gradients may coexist with localized arealization, offering a more integrated view of cortical organization.
Presenter
Ting Xu, Child Mind Institute New York, NY
United States