Nonlinear dynamics model for simulation of multistable perception using reentrant perception-attention-memory coupling

Kurzfassung

Simulation results of multistable perception due to ambiguous visual stimuli are presented which are obtained with a behavioral nonlinear dynamics model using perception–attention–memory coupling. The basic model couples the dynamics of a macroscopic perception state order parameter with an adaptive attention control parameter with reentrant delay T and additive band limited white noise. Quasiperiodic perceptual switching is induced by attention fatigue coupled to the perception state, corresponding to Ditzinger and Haken (1989). As a new feature memory effects are introduced by allowing for the slow adaptation of the perception bias parameter via coupling to the perception state. The simulations exhibit long range correlations of the perceptual duration times in agreement with recent experimental results of Gao et al. (2006). They are determined via the self similarity (Hurst) parameter H of the reversal time series (H > 0.5). Deviations of the simulated reversal time statistics from the Gamma-distribution as typically observed in experiments, increase with decreasing memory time constant and attention noise. Mean perceptual duration times of 2 – 5 s are predicted in agreement with experimental results reported in the literature, if a feedback delay T of 40 ms is assumed which is typical for Thalamo-cortical reentrant loops. Numerically determined perceptual transition times of 3 – 5 T are in reasonable agreement with stimulus–conscious perception delay of 150 – 200 ms. Initial periodic stimulus simulations yields the reversal rate variation as a function of stimulus off-time in surprisingly good quantitative agreement with experimental results of Orbach et.al.(1966).