Filling-in of the foveal blue scotoma.
The blue-blindness (tritanopia) of the human foveola normally goes unnoticed but can be directly visualized by having observers view a flickering, monochromatic, short-wavelength field. The blue scotoma appears as a tiny dark spot in central vision, the visibility of which depends upon the wavelength of the field and the temporal frequency of modulation. Comparisons of fading times as a function of flicker frequency for the blue scotoma, foveal afterimages and optically stabilized images indicate a common time course, consistent with the hypothesis that perceptual filling-in of the foveal blue scotoma reflects the operation of neural processes similar to those involved in fading and regeneration of stabilized images.
Magnussen
S
S
Brain Research Unit, University of Freiburg, Hansastrasse 9, D-79104 Freiburg, Germany. svein.magnussen@psykologi.uio.no
Spillmann
L
L
Stürzel
F
F
Werner
J S
JS
D000360:Afterimage / Q000502:physiology; D005425:Flicker Fusion; D006801:Humans; D009898:Optic Disk / Q000502:physiology*; D010466:Perceptual Closure / Q000502:physiology*