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Demonstration of peripheral visual fading, or Troxler effect. Fixate precisely on the red spot, while paying attention to the bluish annulus. After a few seconds, the annulus will disappear, and the red spot will appear to be surrounded by a completely white field. Eye movement immediately brings the blue annulus back to perception. From MartinezConde S, Macknik SL, Hubel DH: The role of fixational eye movements in visual perception. Nat Rev Neurosci 5:229-240, 2004. Courtesy of Susana Martinez-Conde, PhD.

Demonstration of peripheral visual fading, or Troxler effect. Fixate precisely on the red spot, while paying attention to the bluish annulus. After a few seconds, the annulus will disappear, and the red spot will appear to be surrounded by a completely white field. Eye movement immediately brings the blue annulus back to perception. From MartinezConde S, Macknik SL, Hubel DH: The role of fixational eye movements in visual perception. Nat Rev Neurosci 5:229-240, 2004. Courtesy of Susana Martinez-Conde, PhD.

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... though perfect retinal stabi- lization is most easily achieved under laboratory conditions, objects fade in our visual periphery quite often in nor- mal vision. We are usually unaware of the process. Peripheral fading of sta- tionary objects was first noticed by Troxler in the early 1800s (Fig. 1). He reported that, under voluntary fixation, stationary objects in the periphery of vision tend to fade and disappear. 10 In the late 1950s, Clarke made a connec- tion between Troxler fading and the fading of stabilized images in the labo- ratory, and attributed both phenomena to neural adaptation. 2,3 The simplest explanation for ...

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