Kolloquien
Sommersemester 2022
URL zum ICS-Kalender dieses Seminars
Kirchhoff-Institut für Physik, Otto-Haxel-Hörsaal
freitags 17:15
Vorträge
29.7.2022 17:00
Prof. Dr. Iain Couzin, Max Planck Institute of Animal Behavior and Center for the Advanced Study of Collective Behaviour, University of Konstanz INF 308, Hörsaal 1
A central challenge for animals when alone, or when grouping with others, is deciding
where to go. Running, swimming, or flying through the world, animals are constantly
making decisions while on the move—decisions that allow them to choose where to
eat, where to hide, and with whom to associate. Despite this, most studies have
considered only on the outcome of, and time taken to make, decisions. Motion is,
however, crucial in terms of how space is represented by organisms during spatial
decision-making. Employing a range of new technologies, including automated
tracking, computational reconstruction of sensory information, and immersive
‘holographic’ virtual reality (VR) for animals, experiments with fruit flies, locusts and
zebrafish (representing aerial, terrestrial and aquatic locomotion, respectively), I will
demonstrate that this time-varying representation results in the emergence of new and
fundamental geometric principles that considerably impact decision-making.
Specifically, we find that the brain encodes space in a non-Euclidean manner and
spontaneously reduces multi-choice decisions into a series of abrupt (‘critical’) binary
decisions in space-time, a process that repeats until only one option—the one
ultimately selected by the individual—remains. Due to the critical nature of these
transitions (and the corresponding increase in ‘susceptibility’) even noisy brains are
extremely sensitive to very small differences between remaining options (e.g., a very
small difference in neuronal activity being in “favor” of one option) near these locations
in space-time. This mechanism facilitates highly effective decision-making, and is
shown to be robust both to the number of options available, and to context, such as
whether options are static (e.g. refuges) or mobile (e.g. other animals). In addition, we
find evidence that the same geometric principles of decision-making occur across
scales of biological organisation, from neural dynamics to animal collectives,
suggesting they are fundamental features of spatiotemporal computation.