Talk by Dr. René Doursat
Research Group in Biomimetics (GEB), Universidad de Málaga (UMA), Spain
Complex Systems Institute, Paris (ISC-PIF), CREA, CNRS and Ecole Polytechnique, France
- 15 Mar 2012 14:30
- 15 Mar 2012 15:30
Morphogenetic “neuron flocking”:
The dynamic self-organization of neural activity into mental shapes
My aim is to contribute to a new research focus on the theoretical modeling of the “shapes” of multiscale spatiotemporal phenomena in large neural populations. I wish to emphasize the “complex systems” view of the brain as a recurrent network chiefly occupied with its own intrinsic, emergent activity (sometimes also called “ongoing activity”, although this term is more evocative of a background nuisance than a core function). Traditionally, neural models have followed a rather naive paradigm of input/output signal processing, in which the system is considered passive and essentially stimulus-driven. We should now encourage a recent trend of computational neuroscience to move away from this linear reduction, in order to explore a dynamical paradigm of active self-organization. In this paradigm, stimuli only trigger or distort preexisting internal states, which have been molded and imprinted in synaptic connections during development and Hebbian-like learning. At one or several appropriate mesoscopic levels, the neocortex could be construed as a “pattern formation machine”, generating specific dynamical regimes made of myriads of bioelectrical neuronal signals – not unlike many other biological collective phenomena such as bird flocking, ant colonies or, closer to neurons, multicellular development. Dynamical “neuron flocking”, for its part, happens in phase space and across a complex network topology: What are the emergent mesoscopic objects of its dynamics? Can we characterize their fine spatiotemporal structure through experimental data and/or theoretical models? How are they are endogenously produced by the neuronal substrate – and exogenously evoked and perturbed by perceptual stimuli? How do they interact (bind and compose, breakup and compete) with each other and with motor action? I will present a few of my studies that have started to address these important questions of dynamical neural assembly and shape formation.