title: Differential ambiguity reduces grouping of metastable objects.
abstract: Two coaxial, ambiguously rotating objects tend to be perceived as corotating. Such grouping could be the consequence of bottom-up, cooperative interactions between the stimuli, or the top-down selection of object properties consistent with a model of the objects or scene. However, we find that the coupling between an ambiguous and unambiguous object is sharply reduced, presenting a challenge for both explanations of grouping. We describe experiments that support the idea that top-down feedback is necessary to select and stabilize a perceptual interpretation for ambiguous figures. Reduced coupling between objects of differing ambiguity can be explained if the feedback is global and proportional to ambiguity.
authors.affiliation: Department of Biomedical Engineering and Vision Science Research Center, University of Alabama at Birmingham, Birmingham, AL 35294, USA. jkgrossmann@vsrc.uab.edu
authors.forename: Jon K
authors.initials: JK
authors.lastname: Grossmann
authors.forename: Allan C
authors.initials: AC
authors.lastname: Dobbins
mesh_terms: D015350:Contrast Sensitivity / Q000502:physiology; D030141:Feedback, Psychological / Q000502:physiology; D006801:Humans; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D009903:Optical Illusions / Q000502:physiology; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods; D011601:Psychophysics; D014793:Visual Cortex / Q000502:physiology