Directing visual attention by subliminal cues

Unconscious attention shift has been proven to be automatic, effortless, and unresisting; however, whether it is applicable to images of complex scene remains to be verified. We propose a novel method for directing human visual attention by flashing a short-duration visual stimulus before presenting the image. This method directs viewer´s visual attention to an arbitrary location in the image without engaging the viewer´s awareness. Unlike previous studies using simple stimuli (e.g. simple geometric figures, image of uniform color, or artificial white-noise), we use complex color images for guiding unconscious visual attention in real-world. To our best knowledge, this is the first study demonstrating that short-duration cues presented at arbitrary locations can attract human visual attention in a complex scene. The proposed method is useful for applications that require efficient and unresisting attention shift to the target image area.