Symbols in both panels plot the recovery of response amplitude for subject O.A.R.M., following bleaching exposures of different duration at the highest intensity (3000 cd m^{−2}), after correction for non-linearity of the response–intensity relation and normalization to the dark-adapted level, as described in the text. Curves in each panel plot the optimized global fit of the family of theoretical recoveries, for variation of the single parameter: τ (in *A,* exponential fit) or *v* (in *B,* rate-limited fit). Each colour denotes a different duration of bleaching exposure, as indicated in the key, and the fitting procedure optimized the dark-adapted amplitude, *r*_{DA}, and bleach level, *B,* for each individual recovery. *A,* global fit of the exponential formulation, specified by , yielded *t* = 1.02 min. *B,* global fit of the rate-limited formulation, specified by with *K*_{m}= 0.2, yielded *v* = 0.5 min^{−1}. The estimates of dark-adapted amplitude *r*_{DA} differ slightly, depending on whether the recoveries were fitted with the exponential or rate-limited model, and hence the normalization is slightly different between the two panels. The fitting was performed using measurements at times extending to 4.5–8 min postbleach for each recovery, though the time axis is not plotted beyond 3.7 min. The respective durations and numbers of repetitions of the bleaching exposures were: 10, 15, 20, 40 and 60 s exposures; with 7, 3, 6, 4, and 3 repetitions. Each point plots the mean ± s.e.m. determined over a postbleach interval of 20 s (two sets of 15 flashes for each bleach), and therefore is averaged from up to 210 flash presentations.

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