When is motion 'motion'?
Examples of visual motion have become more and more abstract over the years, leading up to 'third-order' stimuli where direction is actually determined by the observer through top - down attention. But how far can this be pushed--are there motion stimuli that are yet more arbitrary and abstract? Actually, there is a broad class of 'conceptual motion' stimuli--things like a moving grating of faces, or a shifting pattern of words--that are perfect analogs to traditional 'perceptual motion' stimuli, solvable by the same motion computation and for which observers can readily make direction-of-motion judgments. Interestingly though, these do not produce a sensation of motion (among other automatic consequences of motion detection). Here we compare a luminance-based perceptual motion stimulus to a semantic-based conceptual motion stimulus to contrast the psychophysical hallmarks of these motion categories.
University of Massachusetts, Boston, MA 02125-3393, USA. erik.blaser@umb.edu
Erik
E
Blaser
George
G
Sperling
D006801:Humans; D009038:Motion; D009039:Motion Perception / Q000502:physiology*; D009903:Optical Illusions; D010775:Photic Stimulation; D011601:Psychophysics; D012660:Semantics