Task modulation of face part selectivity. A–E, Trustworthiness judgment task. F–J, Dominance judgment task. A, F, Neurons that had a significantly greater FR when fixating on the eyes compared with the mouth (selection by two-tailed t test in a time window of −200 ms before fixation onset to 200 ms after fixation offset). B, G, Neurons that had a significantly greater FR when fixating on the mouth compared with the eyes. Fixations are sorted by fixation duration (black line shows start of the next saccade). Fixation onset is t = 0. Asterisks indicate a significant difference between fixations on the eyes and mouth in that bin (p < 0.05, two-tailed t test, after Bonferroni correction; bin size = 100 ms). C–E, H–J, Population summary of all eye-mouth-selective. C, H, Average normalized FR of eyes-preferring neurons. D, I, Average normalized FR of mouth-preferring neurons. Shaded area denotes ±SEM across neurons. Asterisks indicate a significant difference between the fixation categories in that bin (p < 0.05, two-tailed t test, after Bonferroni correction). E, J, Single-fixation analysis using the FSI (Materials and Methods). Shown is the cumulative distribution of the single-fixation response of fixation-aligned eyes-preferring and mouth-preferring neurons for fixations on the eyes and mouth.