Figure 5.

The effect of age on critical spacing/eccentricity. Critical spacing to eccentricity ratio for individuals plotted as a function of age. (a) Critical spacing measured directly with the spacing task, where flanker-to-target separation was varied while letter size remained constant. (b) Critical spacing determined from results of the crowded acuity task using Equation 1. There was no significant effect of age on the critical spacing-to-eccentricity ratio, which was in the region of 0.5 and thus agrees with Bouma's law (dashed lines). Error bars represent SEM.