Integration Without Awareness

Abstract

Human conscious awareness is commonly seen as the climax of evolution. However, what function—if any—it serves in human behavior is still debated. One of the leading suggestions is that the cardinal function of conscious awareness is to integrate numerous inputs—including the multitude of features and objects in a complex scene—across different levels of analysis into a unified, coherent, and meaningful perceptual experience. Here we demonstrate, however, that integration of objects with their background scenes can be achieved without awareness of either. We used a binocular rivalry technique known as continuous flash suppression to induce perceptual suppression in a group of human observers. Complex scenes that included incongruent objects escaped perceptual suppression faster than normal scenes did. We conclude that visual awareness is not needed for object-background integration or for processing the likelihood of an object to appear within a given semantic context, but may be needed for dealing with novel situations.