Fig. 1

The mfPOP stimulus protocols. All 5 protocols had 44 stimulus regions arranged in 5 rings, a and b. Pseudo-random sequences governed when any one stimulus region would be shown for 33 ms. Each region was presented 96 times. The presentation sequence meant that although the stimuli could overlap (c) in practice they never did. a to c show the layout of stimuli for the wide-field stimuli d,f,h. The layout of the macular stimuli, e,g, was the same, just isomorphically scaled by a factor of two. In d to h left and right halves of the 2- and 3-ring stimulus arrays are presented separately to aid visibility. d) The Blue Wide-field stimulus, e) Yellow Macular, f) Yellow Wide-field, g) red-green (RG) Macular, h) RG Wide-field. Different parts of the fields of normal persons differ in sensitivity, therefore individual regions varied in intensity to try to balance the size of the responses from each region