Abstract-Recent neurobiological findings suggest that the brain solves perceptual decision-making tasks by means of a dynamic competition in which evidence is accumulated in favor of the alternatives. However, it is unclear if and how the same process applies in more complex, real-world tasks such as the categorization of ambiguous visual scenes and what elements are considered as evidence in this case. Furthermore, dynamic decision models typically consider evidence accumulation as a passive process disregarding the role of active perception strategies. In this article, we adopt the principles of dynamic competition and active vision for the realization of a biologicallymotivated computational model, which we test in a visual categorization task. Furthermore, our system uses predictive power of the features as the main dimension for both evidence accumulation and the guidance of active vision. Comparison of human and synthetic data in a common experimental set-up suggests that the proposed model captures essential aspects of how the brain solves perceptual ambiguities in time. Our results point to the importance of the proposed principles of dynamic competition, parallel specification and selection of multiple alternatives, prediction, and active guidance of perceptual strategies for perceptual decision-making and the solution of perceptual ambiguities, and suggest that they could apply to both the simple perceptual decision problems studied in neuroscience and the more complex ones addressed by vision research.