Value-driven attentional and oculomotor capture during goal-directed, unconstrained viewing

Abstract

Covert shifts of attention precede and direct overt eye movements to stimuli that are task relevant or physically salient. A growing body of evidence suggests that the learned value of perceptual stimuli strongly influences their attentional priority. For example, previously rewarded but otherwise irrelevant and inconspicuous stimuli capture covert attention involuntarily. It is unknown, however, whether stimuli also draw eye movements involuntarily as a consequence of their reward history. Here, we show that previously rewarded but currently task-irrelevant stimuli capture both attention and the eyes. Value-driven oculomotor capture was observed during unconstrained viewing, when neither eye movements nor fixations were required, and was strongly related to individual differences in visual working memory capacity. The appearance of a reward-associated stimulus came to evoke pupil dilation over the course of training, which provides physiological evidence that the stimuli that elicit value-driven capture come to serve as reward-predictive cues. These findings reveal a close coupling of value-driven attentional capture and eye movements that has broad implications for theories of attention and reward learning.

Fig. 1

Sequence of events and time course for a trial during training (a) and at test (b) in Experiment 1. Targets were defined as the red or green circle during training and as the unique shape at test (either a circle among diamonds or a diamond among circles). Participants reported the identity of an oriented bar contained within the target stimulus. Monetary reward was delivered in the training phase, which varied probabilistically with the color of the target. The valuable distractor in the test phase consisted of a nontarget stimulus rendered in the color of a formerly reward-predictive target

Fig. 2

a Mean percent change in pupil diameter (relative to the 200-ms interval before trial onset) by trial block during the training phase of Experiment 1. b Mean percent change in pupil diameter over time by trial block in response to the target display in the training phase. The error bars reflect the within-subjects SEM (Loftus & Masson, 1994)

Fig. 3

Manual response time (a) and accuracy (b) by condition during the test phase of Experiment 1. The error bars reflect the within-subjects SEM. *p < .05; **p < .01

Fig. 4

a Percentage of initial eye movements to the side of the visual field containing the target by distractor condition in Experiment 1. b Scatterplot of visual working memory capacity versus value-driven oculomotor capture (difference in percentage of initial eye movements toward the side of the display opposite the target on trials with a high-value distractor opposite the target vs. on trials with no distractor). The error bars reflect the within-subjects SEM. *p < .05; ***p < .001

Fig. 5

Mean percent change in pupil diameter (relative to the 200-ms interval before trial onset) by trial block during the training phase of Experiment 2