Dynamics of Perceptual Bistability

When experiencing an ambiguous sensory stimulus (e.g., the vase-faces image) subjects may report haphazard alternations (time scale, seconds) be- tween the possible interpretations. Various dynamical models that implement neuronal competition with reciprocal inhibition between neuronal popula- tions show alternations behaving as noisy oscillators or as bistable systems subject to noise-driven switching. Slow negative feedback, neuronal firing adaptation or synaptic depression, sets the basic time scale (seconds) for switching. A minimal statistical model based on alternating renewal pro- cesses (with durations described by gamma distributions) captures various aspects of the percept time series.