Ila Fiete, PhD

Professor, Department of Brain and Cognitive Sciences

MIT

Host(s): Mingye (Christina) Wang (Graduate Student), Stefano Fusi (Faculty)

Modeling the emergence of complex cortical structure from simple precursors in the brain: maps, hierarchies, and modules

Modular and hierarchical structures are ubiquitous in the brain. Two distinct hypotheses for such morphogenesis involve genetic specification (the positional information hypothesis) or spontaneous structure emergence from symmetry breaking (the pattern formation hypothesis). Indeed, there is rich evidence supporting both hypotheses in different systems, and more recently evidence that both systems might interact, for instance with genetic specification providing an initial but relatively low-information scaffold of positional guidance and pattern formation constructing sharper structures by bootstrapping from this guidance. In this talk, I will consider the emergence of two systems in the brain: the visual processing hierarchy with topographic structure, and a modular cognitive circuit consisting of functionally independent grid cell networks that compute spatial location from velocity cues as animals move and navigate the world. I will describe how simple activity-driven growth and competition rules can lead to the emergence of topographically ordered sensory processing hierarchies, and how genetically specified smooth gradients with purely local recurrent interactions on two scales can lead to global module emergence. In sum, simple growth rules, local interactions and smooth gradients can interact to produce rich emergent order on multiple scales in the form of maps, modules, and hierarchies, with predictions that bridge scales from genes to connectivity to function.

Relevant Publications:

Self-organized emergence of modularity, hierarchy, and mirror reversals from competitive synaptic growth in a developmental model of the visual pathway

From smooth cortical gradients to discrete modules: A biologically plausible mechanism for the self-organization of modularity in grid cells

Venue Information:

Speaker Location: Jerome L. Greene Science Center, Kavli Auditorium, 9th Floor Lecture Hall

The Columbia Neuroscience Seminars have been organized to help build community and collaboration among researchers interested in this broad field across campus. The in-person activities, including the talks, provide meaningful interactions for the speakers, many of whom have traveled a long way to visit Columbia. However, if you are a Columbia researcher on another campus and are unable to attend the talk at the Jerome L. Greene Science Center, please email [email protected] at least 48 hours in advance to request an individual, one-time Zoom link (livestream only, no Q&A). 

If you have a short- or long-term accommodation request (medical issue, travel, other concerns, etc.), or any other questions, please also reach out to [email protected].

Tuesdays@10 is a signature Zuckerman Institute initiative that aims to expose researchers at all levels to high-quality science and stimulate scientific discourse. The speakers featured in this series represent various fields and techniques in neuroscience, and include invited guests of the Columbia Neuroscience Seminars, the Zuckerman Institute's Local Circuits Affiliates Program, and other special seminar series through a combined, collaborative effort of one or more of the following: Columbia's Zuckerman Institute, the Center for Precision Psychiatry, the Department of Neuroscience, the Doctoral Program in Neurobiology and Behavior and the Columbia Translational Neuroscience Initiative, and with support from the Kavli Institute for Brain Science. 

More information and a full schedule can be found here.