Spatial summation of foveal increments and decrements.
D000221:Adaptation, Ocular; D005403:Fixation, Ocular; D005584:Fovea Centralis / Q000502:physiology*; D006801:Humans; D008027:Light; D008266:Macula Lutea / Q000502:physiology*; D008297:Male; D008954:Models, Biological; D010783:Photometry; D011336:Probability; D011594:Psychometrics; D013028:Space Perception / Q000502:physiology*