Multistable binocular feature-integrated percepts are frozen by intermittent presentation.

When two different stimuli are presented continuously to each eye, the percept alternates over time between the left-eye stimulus and right-eye stimulus. The perceptual alternation can be slowed or even stopped, however, if the same stimuli are presented intermittently (D. A. Leopold, M. Wilke, A. Maier, & N. K. Logothetis, 2002; J. Orbach, D. Ehrlich, & H. A. Heath, 1963). A basic question is the nature of the persisting neural representation, which mediates the stabilized percept. Is it a representation for the dominant eye, for the stimulus in one eye or for a feature-integrated percept incorporating features presented separately to each eye? We define a feature-integrated percept as one constructed by the visual system but which never is presented as a stimulus. This was tested using a feature-integrated percept resulting from rivalrous, equiluminant chromatic patterns (S. W. Hong & S. K. Shevell, 2009). Measurements showed that the feature-integrated percept was stabilized by intermittent viewing: when the percept at the end of the initial viewing period was feature-integrated, this same integrated percept was seen on subsequent intermittent presentations. The results showed that the stabilized percept from these intermittent rivalrous patterns was due to a persisting neural representation at or after binocular feature integration, not to a persisting dominant eye or neural representation of a retinal stimulus.