title: Collective Activity of Many Bistable Assemblies Reproduces Characteristic Dynamics of Multistable Perception.
abstract: The timing of perceptual decisions depends on both deterministic and stochastic factors, as the gradual accumulation of sensory evidence (deterministic) is contaminated by sensory and/or internal noise (stochastic). When human observers view multistable visual displays, successive episodes of stochastic accumulation culminate in repeated reversals of visual appearance. Treating reversal timing as a "first-passage time" problem, we ask how the observed timing densities constrain the underlying stochastic accumulation. Importantly, mean reversal times (i.e., deterministic factors) differ enormously between displays/observers/stimulation levels, whereas the variance and skewness of reversal times (i.e., stochastic factors) keep characteristic proportions of the mean. What sort of stochastic process could reproduce this highly consistent "scaling property?" Here we show that the collective activity of a finite population of bistable units (i.e., a generalized Ehrenfest process) quantitatively reproduces all aspects of the scaling property of multistable phenomena, in contrast to other processes under consideration (Poisson, Wiener, or Ornstein-Uhlenbeck process). The postulated units express the spontaneous dynamics of attractor assemblies transitioning between distinct activity states. Plausible candidates are cortical columns, or clusters of columns, as they are preferentially connected and spontaneously explore a restricted repertoire of activity states. Our findings suggests that perceptual representations are granular, probabilistic, and operate far from equilibrium, thereby offering a suitable substrate for statistical inference.
  
  
  
  Spontaneous reversals of high-level perception, so-called multistable perception, conform to highly consistent and characteristic statistics, constraining plausible neural representations. We show that the observed perceptual dynamics would be reproduced quantitatively by a finite population of distinct neural assemblies, each with locally bistable activity, operating far from the collective equilibrium (generalized Ehrenfest process). Such a representation would be consistent with the intrinsic stochastic dynamics of neocortical activity, which is dominated by preferentially connected assemblies, such as cortical columns or clusters of columns. We predict that local neuron assemblies will express bistable dynamics, with spontaneous active-inactive transitions, whenever they contribute to high-level perception.
authors.affiliation: Institute of Biology, Otto-von-Guericke University, 39120 Magdeburg, Germany, Istituto Superiore di Sanità, 00161 Rome, Italy, and.
authors.forename: Robin
authors.initials: R
authors.lastname: Cao
authors.affiliation: Institute of Psychology, Otto-Friedrich-University, 96047 Bamberg, Germany.
authors.forename: Alexander
authors.identifier: 0000-0002-8738-8591
authors.initials: A
authors.lastname: Pastukhov
authors.affiliation: Istituto Superiore di Sanità, 00161 Rome, Italy, and.
authors.forename: Maurizio
authors.identifier: 0000-0002-2356-4509
authors.initials: M
authors.lastname: Mattia
authors.affiliation: Institute of Biology, Otto-von-Guericke University, 39120 Magdeburg, Germany, Center for Behavioral Brain Sciences, 39120 Magdeburg, Germany, jochen.braun@ovgu.de.
authors.forename: Jochen
authors.identifier: 0000-0002-8886-078X
authors.initials: J
authors.lastname: Braun
mesh_terms: D000200:Action Potentials / Q000502:physiology; D001921:Brain / Q000166:cytology / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*; D017711:Nonlinear Dynamics; D010775:Photic Stimulation; D013269:Stochastic Processes; D014796:Visual Perception / Q000502:physiology*
keywords: attractor cell assemblies; birth-death process; cortical columns; first-passage time; multistable perception; scaling property