Simulating bistable perception with interrupted ambiguous stimulus using self-oscillator dynamics with percept choice bifurcation

Abstract

A behavioral stochastic self-oscillator model is used for simulating interrupted ambiguous stimulus-induced percept reversals. The results provide further support for a dynamical systems foundation of cognitive and psychological problems as discussed in detail within the context of Gestalt psychology by Wagemans et al. (Concept Theor Found Psychol Bull 138(6):1218-1252, 2012), and for coordination dynamics of the brain (Kelso in Philos Trans R Soc B 367:906-918, 2012). Statistical evaluation of simulated reversal time series predicts a maximum of the percept reversal rate that conforms with a number of results in the literature. The macroscopic model is based on two inhibitorily coupled sets of three coupled nonlinear equations, one triplet for each percept. The derivation of our specific dynamics equations is based on a drastically simplified field theoretical approach using well-known phase synchronization for explaining brain dynamics on the macroscopic EEG level. The degree of coherence (contrast μ, 0 ≤ μ ≤ 1) of the superimposed fields required for onset of bistable dynamics is related to a phase synchronization index of EEG fields, and it is used in the present context as ambiguity control parameter. For quantitative agreement with the experimental data, the addition of a stochastic Langevin force term in the attention equation proved essential. Formal analysis leads to a quantification of well-known "cognitive inertia" and supports the interplay between percept choice (bifurcation) dynamics during stimulus onset and adaptive gain (attention fatigue) driven quasiperiodic percept reversals.

The three-second “subjective present”: A critical review and a new proposal.

“…Several findings indicate that adaptation plays a role in shifts of perception: in simple terms, neurons for one interpretation become adapted or fatigued to a point where they are less excited than neurons for the alternative interpretation, which then take over (Gómez et al, 1995). Recent papers have developed theoretical models of reversibility in bistable percepts that have proposed processes specific to the phenomenon (Furstenau, 2014; Lee, 2014; and see also Holcombe & Seizova-Cajic, 2008). Thus, the time scale of, and effects of manipulated variables on, perceptual reversals reflects, not a general temporal integration process constructing the “subjective present,” but a specific feature of visual processing (fatigue or adaptation) that happens to occur on a similar (though not identical) time scale.…”

Temporal integration by multi‐level regularities fosters the emergence of dynamic conscious experience

“…Meng and Tong instructed subjects to hold one of the two rival stimuli dominant for as long as possible 50 . The results showed only a weak and statistically unreliable attentional modulation effect over the dynamics of BR, in contrast to the strong attention modulation effects observed in studies of perceptual reversals for other bistable stimuli 50–52 . Moreover, Chong et al.…”

“…50 The results showed only a weak and statistically unreliable attentional modulation effect over the dynamics of BR, in contrast to the strong attention modulation effects observed in studies of perceptual reversals for other bistable stimuli. [50][51][52] Moreover, Chong et al found that enhancing task relevance of a rival stimulus (e.g., directing observers' attention to a changing feature of that stimulus) can lengthen perceptual dominance. 53 These attentional modulation effects are not applicable to the current research, as neither voluntary control nor task-driven attentional selection was involved in our behavioral task (i.e., color discrimination).…”