Fig. 3.

Subjects learn to direct their first fixation toward more valuable novel stimuli during a session. (A) The mean (±SEM) proportion of trials where the subjects’ first fixation was toward the more valuable stimulus, as a function of session decile. On the earliest novel trials, subjects’ first fixation direction is not influenced by value. However, as the stimulus values are learned, subjects develop a preference to fixate the more valuable stimulus first. On overtrained trials, subjects consistently fixate the more valuable stimulus first. (B) Logistic fit of the probability of fixating the left stimulus first as a function of left–right stimulus value difference for novel trials. The data are split by session decile. (B, Inset) The regression coefficient (±SE) quantifying the effect of value on fixation direction in each trial decile. On novel trials, first fixation direction is increasingly influenced by stimulus values as the session progresses.