title: Motion-induced blindness and Troxler fading: common and different mechanisms.
abstract: Extended stabilization of gaze leads to disappearance of dim visual targets presented peripherally. This phenomenon, known as Troxler fading, is thought to result from neuronal adaptation. Intense targets also disappear intermittently when surrounded by a moving pattern (the "mask"), a phenomenon known as motion-induced blindness (MIB). The similar phenomenology and dynamics of these disappearances may suggest that also MIB is, likewise, solely due to adaptation, which may be amplified by the presence of the mask. Here we directly compared the dependence of both phenomena on target contrast. Observers reported the disappearance and reappearance of a target of varying intensity (contrast levels: 8%-80%). MIB was induced by adding a mask that moved at one of various different speeds. The results revealed a lawful effect of contrast in both MIB and Troxler fading, but with opposite trends. Increasing target contrast increased (doubled) the rate of disappearance events for MIB, but decreased the disappearance rate to half in Troxler fading. The target mean invisible period decreased equally strongly with target contrast in MIB and in Troxler fading. The results suggest that both MIB and Troxler are equally affected by contrast adaptation, but that the rate of MIB is governed by an additional mechanism, possibly involving antagonistic processes between neuronal populations processing target and mask. Our results link MIB to other bi-stable visual phenomena that involve neuronal competition (such as binocular rivalry), which exhibit an analogous dependency on the strength of the competing stimulus components.
authors.affiliation: Department of Human Biology, University of Haifa, Haifa, Israel; Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Yoram S
authors.initials: YS
authors.lastname: Bonneh
authors.affiliation: Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands; Cognitive Science Center, University of Amsterdam, Amsterdam, The Netherlands; Bernstein Center for Computational Neuroscience, Charité-Universitätsmedizin, Berlin, Germany; Department of Psychology and Center for Neural Science, New York University, New York, New York, United States of America.
authors.forename: Tobias H
authors.initials: TH
authors.lastname: Donner
authors.affiliation: Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Alexander
authors.initials: A
authors.lastname: Cooperman
authors.affiliation: Department of Psychology and Center for Neural Science, New York University, New York, New York, United States of America.
authors.forename: David J
authors.initials: DJ
authors.lastname: Heeger
authors.affiliation: Department of Neurobiology, The Weizmann Institute of Science, Rehovot, Israel.
authors.forename: Dov
authors.initials: D
authors.lastname: Sagi
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010470:Perceptual Masking / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time