Listeners:
Top listeners:
play_arrow
Paul Verschure on consciousness and distributed adaptive control CSN Podcasts
play_arrow
Edvard Moser on grid cells and entorhinal cortex CSN Podcasts
play_arrow
Giacomo Rizzolatti on mirror neurons and action understanding CSN Podcasts
play_arrow
Robert Axelrod on game theory and prisoner's dilemma CSN Podcasts
play_arrow
Adrian Owen on disorders of consciousness and vegetative state CSN Podcasts
play_arrow
Jonathan Whitlock on markerless motion capture and posterior parietal cortex CSN Podcasts
play_arrow
Luis Puelles on neuroanatomy and prosomeric model CSN Podcasts
play_arrow
Zoltan Molnar on subplate neurons and cortical development CSN Podcasts
Episode 6 15.03.2014
play_arrow
PLAY EPISODE
What if the most widely used model of brain connectivity is too crude to capture what actually makes the cortex work? Neuroanatomist Henry Kennedy presents evidence that connection strength, not mere presence or absence of links, is where the real specificity of cortical architecture lies , spanning five orders of magnitude. Subscribe for more from the Convergent Science Network podcast series. Henry Kennedy joins Paul Verschure and Tony Prescott at the BCBT summer school to present his quantitative tract-tracing data from the macaque monkey cortex, challenging the utility of small-world network models for understanding cortical organization. With a connection density of roughly 70 percent among 91 cortical areas, Kennedy argues that binary descriptions of connectivity tell you almost nothing , at that density, everything is virtually connected to everything else. The real information lies in the weights: connection strengths that span five orders of magnitude and follow an exponential distance rule, declining sharply with the physical distance between areas. The discussion reveals that this single exponential distance rule, when used to generate random networks, reproduces many observed properties of the real cortical network , including motif distributions, clique structures, and efficiency measures under progressive thresholding. Kennedy shows that the macaque cortex achieves optimal placement of areas to minimize wiring given these weight constraints, while the mouse brain does not, suggesting fundamentally different organizational principles across species. The comparison between primate and rodent brains reveals that mice have shallower distance-decay functions, fewer cliques, and suboptimal area placement, raising serious questions about using the mouse as a model for primate cortical organization. Key topics include why weighted directed networks are more informative than binary connectivity graphs, how the exponential distance rule generates realistic cortical network properties, what optimal area placement means and how it differs between primates and rodents, why diffusion MRI cannot capture the range of connection strengths revealed by tract tracing, and how cortical folding and surface distances reshape our understanding of the distance rule across species. Part of the Convergent Science Network podcast series from the BCBT Summer School.
Tagged as:
Cortical cortical connectivity Distance Rule Exponential Distance exponential distance rule Orders Magnitude
About the author call_made
Both the triumphs of humanity and its most evil deeds have resulted from collaboration. In a time where humanity is required to aspire to the former and minimize the latter, the question arises of how collaboration arises and why it fails. Surprisingly, this phenomenon, so central to who we are, is not well understood. Hence, a collaborative effort is required to understand collaboration in its full biological, psychological, sociological, cultural, and economic complexity and to translate this understanding into operational impact. This series of podcasts is one step toward achieving these complementary goals. The Collaboration Podcast presents interviews with people who are central orchestrators of collaboration in various domains including business, government, science, art, health, sustainability, and the military. The discussions were conducted by Prof. Dr. Paul F.M.J. Verschure and members of the Program Advisory Committee of the Ernst Strungmann Forum on Collaboration (https://www.esforum.de/forums/ESF32_Collaboration.html) during 2021 and had the goal to sketch a map of opportunities, challenges, and obstacles in human collaboration. The forum took place in May 2022, and now we would like to share this series of interviews with a broader audience. The full report of the Forum will be published in 2023 by MIT Press. The podcast was produced by the Convergent Science Network (https://www.convergentsciencenetwork.org/). Context: The stability of social systems depends critically on realizing sustainable methods of “collaboration,” yet how and by which means collaboration is achieved is not clearly understood; neither are the conditions or processes that lead to its breakdown or failure. Collaboration can be understood as cooperation between agents toward mutually constructed goals. Part of the reason for our lack of understanding is that the phenomenon of collaboration is, by nature, a highly multidisciplinary problem, and effective research into its complexities has been difficult to achieve across the broad range of scientific and technical disciplines involved. The need for a fundamental understanding of collaboration, however, has become increasingly important. Not only does humankind demand answers as it attempts to address critical challenges at multiple scales (e.g., climate change, migration, enhanced automation, social and economic inequality), but ever-increasing technological and economic means of interconnecting people and societies are disrupting long-established, familiar patterns of how we interact. Radical technological changes that are ongoing have the potential to reshape collaboration in ways that are currently hard to predict or influence (e.g., by altering configurations in interaction, information creation, and modes of communication). On one hand, such changes could disrupt hitherto stable forms of collaboration by affecting critical communication channels and traditional roles, as can be observed in the rapidly changing patterns in governance, commerce, and social interaction. Conversely, technology could lead to the emergence of novel, successful forms of collaboration that deviate from traditional “hierarchical” architectures. Evidence of this can be seen in areas as diverse as highly automated manufacturing plants, the open science movement, collaborative software repositories, user-centered services, and the sharing of economy-based modes of organization. Without a fundamental understanding of the mechanisms, processes, and boundary conditions of collaboration, it is not possible to evaluate or predict which of these possible scenarios are sustainable or even plausible. The Forum “How Collaboration Arises and Why it Fails” (May 8–13, 2022, Location: Frankfurt am Main, Germany) Chairs: Andreas Roepstorff and Paul Verschure Program Advisory Committee: Jenna Bednar, Julia R. Lupp, Bhavani R. Rao , Andreas Roepstorff, Ferdinand von Siemens, and Paul Verschure
Exploring the convergence of neuroscience, robotics, and AI through conversations with leading researchers since 2010.
A project of the Convergent Science Network Foundation.
© CSN Podcasts. Developed by IMCreative & WEBC
✖
✖
Are you sure you want to cancel your subscription? You will lose your Premium access and stored playlists.
✖
Be the first to leave a comment