Figure 4
From: Similar contrast sensitivity functions measured using psychophysics and optokinetic nystagmus
Proportion of correct reports of stimulus direction based on (a–d) our OKN analysis and (e–h) perceptual report. Data are shown for four observers tested with five spatial frequencies. Fits (coloured lines) based on a Weibull function provide a good account of the data. Note similarity of fits across conditions, with one notable exception at 1.9 c/deg in Fig. 4b,f, where the fits differ due to the low contrast conditions. Observer CZ (Fig. 4d) exhibited reversed OKN and our analysis took this into account. Had it not, performance would have been substantially poorer (fits shown by black lines).
