Fig. 9.

Effect of the signal contrast on EMI and number of courses ($\mathrm{\Delta }$ is the difference of the considered parameter from $-50$ to $-30\mathrm{HU}$). (a) $\mathrm{\Delta }\mathrm{EMI}$ versus $\mathrm{\Delta }\text{course}$. (b) Decomposition of the EMI in its two components: $\mathrm{\Delta }\text{saccadic}$ amplitude versus $\mathrm{\Delta }\text{crossover}$ per second. Note: the symbols correspond to the four reader categories defined in Fig. 3(a).