It is shown that for the areas tested in the tangent screen field, whether the critical flicker fusion for flicker-to-fusion is higher or lower than that for fusion-to-flicker, depends on the rate at which the test stimulus changes when the continuous method of presentation is used. The test conditions described are for 24 normal subjects between the ages of 20 and 29 years in nine areas of the central visual field. The findings support the work of Makneke1 and of Dillon2 for central fixation and extend them to include the central field as represented by the areas tested. Some theoretical implications are discussed.
Lovekin LG. Alteration of the Flicker Fusion FieldProduced by Presenting the Stimulus at Different Rates. Arch Ophthalmol. 1968;79(3):304-310. doi:10.1001/archopht.1968.03850040306015