A schematic diagram showing how the time to complete the familiarity check, t(L1), relates to the time require to complete lexical access, t(L2), shift attention, t(A), and complete saccadic programming, t(M1) + t(M2), all as a function of word-processing difficulty. As the figure indicates, the amount of time that is available for parafoveal processing of word n+1 (i.e., the time between when attention shifts to word n+1 and when the eyes actually move to word n+1) varies as a function of the processing difficulty of word n.