Gaze dynamics of feature-based distractor inhibition under the prior-knowledge and expectation

Prior information about distractor facilitates selective attention to task-relevant items and helps the optimization of oculomotor planning. Particularly, feature-based attentional inhibition could be benefited from the pre-knowledge of critical features of the distractors. In the present study, we capitalized on gaze-position decoding to examine the dynamics of attentional deployment in a feature-based attentional task that involved two groups of dots (target/distractor dots) moving toward different directions. Specifically, this measurement revealed how pre-knowledge of the target’s or distractor’s direction modulated real-time feature-based attentional bias. In Experiment 1, participants were provided with target cues indicating the moving direction of target dots. The results showed that participants were biased towards the cued direction and tracked the target dots throughout the task period. In Experiment 2 and Experiment 3, participants were provided with cues that informed the moving direction of distractor dots. The results showed that participants would continuously monitor the distractor’s direction when the distractor cue varied on a trial-by-trial basis (Experiment 2). However, when the to-be-ignored distractor direction remained constant (Experiment 3), participants would strategically bias their attention to the distractor’s direction before the cue onset and reduce the cost of re-deployment of attention between trials. These results suggest that monitoring the distractor’s feature is a prerequisite for feature-based attentional inhibition and this process is facilitated by the predictability of the distractor’s feature.