Collective Activity of Many Bistable Assemblies Reproduces Characteristic Dynamics of Multistable Perception

Professorship/Faculty: General Psychology and Methodology  
Author(s): Cao, Robin; Pastukhov, Alexander  ; Mattia, Maurizio; Braun, Jochen
Title of the Journal: Journal of Neuroscience
ISSN: 0270-6474
Year of publication: 2016
Volume: 36
Issue: 26
Pages: 6957-6972
Language(s): English
DOI: 10.1523/JNEUROSCI.4626-15.2016
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.
Keywords: attractor cell assemblies, birth-death process, cortical columns, first-passage time, multistable perception
Peer Reviewed: Ja
International Distribution: Ja
Document Type: Article
Year of publication: 25. November 2016