The relationship between spatial contrast sensitivity and visual field loss was examined using an artificial scotoma technique. Central-field contrast sensitivity was measured in normal subjects both with and without artificial, central scotomata of varying sizes and using a forced-choice psychophysical method. Previously it was found that the type of contrast sensitivity loss observed with 5 degree grating field depended both on the size of the artificial scotoma and on temporal factors associated with grating presentation. Small artificial scotoma produced a predominatly high spatial frequency loss. Larger scotomata produced a middle and low spatial frequency loss which was acentuted by turning grating contrast on and off abruptly as opposed to gradually. Research during this past year, has shown that similar findings are obtained when grating field size and artificial scotoma size are increased by a factor of approximately three.
