Perceptual Priming by Invisible Motion

Abstract

When observers see motion that is not really there, they can nonetheless show evidence of motion priming. And when observers do not see motion that is really there, they also show evidence for motion priming. Evidently, the process responsible for establishing motion correspondence is sensitive to contextual information, and this sensitivity is modulated at preconscious levels of visual analysis.

Temporal structure coding with and without awareness

“…In CFS, a stream of salient patterns flashed to the dominant eye renders the signal presented to the non-dominant eye invisible (Tsuchiya & Koch, 2005;Tsuchiya, Koch, Gilroy, & Blake, 2006). Relying on previous results (Anstis, Giaschi, & Cogan, 1985;Blake, Ahlström, & Alais, 1999;Geisler, 1999;Jordan, Fallah, & Stoner, 2006;Kruse, Stadler, & Wehner, 1986;Rajimehr, Vaziri-Pashkam, Afraz, & Esteky, 2004;Ramachandran, 1975;Troje, Sadr, Geyer, & Nakayama, 2006;Wiesenfelder & Blake, 1991), we assumed that in the presence of temporal integration, being exposed to apparent motion with a particular direction or a point-light walker with kinematic features (hereafter the adaptor) would bias the way subsequent ambiguous motion is perceived (i.e., apparent motion with ambiguous direction, or point-light walkers with ambiguous gender). By varying parametrically the kinematics and visibility of apparent and biological motion adaptors, we could quantitatively estimate the extent of temporal integration with and without awareness.…”

Priming by motion too rapid to be consciously seen

“…This is the case even when primes are rendered invisible by backward masking by the subsequent target (Fehrer & Raab, 1962;Klotz & Neumann, 1999;Mattler, 2003;Neumann & Klotz, 1994;Schmidt, 2000Schmidt, , 2002Vorberg et al, 2003Vorberg et al, , 2004Wolff, 1989). Motion priming has been demonstrated with a different type of measure: The direction of a moving prime will bias the perceived direction of a subsequent ambiguous apparent motion target (Anstis & Ramachandran, 1987;Blake, Ahlstrom, & Alais, 1999;Pantle, Gallogly, & Piehler, 2000;Piehler & Pantle, 2001;Pinkus & Pantle, 1997;Ramachandran & Anstis, 1983). We will refer to this biasing effect as disambiguation.…”

“…We will refer to this biasing effect as disambiguation. Blake et al (1999) demonstrated motion priming by a stimulus outside awareness by showing that disambiguation priming can occur even when the prime is presented to an eye in which phenomenal vision is suppressed because of binocular rivalry.These studies of priming by invisible stimuli have depended on processes that disrupt conscious awareness to make normally visible stimuli invisible. To understand the mechanisms of unconscious priming in such studies, one must know the level at which the disrupting process operates.…”

“…We will refer to this biasing effect as disambiguation. Blake et al (1999) demonstrated motion priming by a stimulus outside awareness by showing that disambiguation priming can occur even when the prime is presented to an eye in which phenomenal vision is suppressed because of binocular rivalry.…”

“…In another condition, the prime was followed by a target with an ambiguous rotation direction, and subjects reported the direction that was seen. This allowed us to evaluate the priming produced by our stimuli using the disambiguation measure that has been employed in most earlier motion priming studies (Anstis & Ramachandran, 1987;Blake et al, 1999;Pantle et al, 2000;Piehler & Pantle, 2001;Pinkus & Pantle, 1997;Ramachandran & Anstis, 1983).…”