Visual working memory (VWM) is directionally linked to oculomotor control. Hollingworth & Luck (2009) showed that corrective saccades can be biased towards distractors whose feature matches the content of VWM. Here, we investigated whether this effect is modulated by task demands.
20 participants had to memorize a color hue and then to discriminate it from another hue from a different (Easy condition) or the same color category (Difficult condition). In between encoding and test, they performed a gaze-contingent saccade task. During the saccade to the target, the position of items shifted and the color of a neighboring distractor changed to a color (dis)similar to the memorized one.
VWM performance was higher in the Easy compared to the Difficult condition, showing successful manipulation of task demands. Replicating previous findings, corrective saccades were biased more towards the distractor when it matched VWM content than when it did not. Importantly, saccade biases towards the distractor occurred more frequently in the Difficult compared to the Easy condition, indicating the influence of task demands on oculomotor biases. Moreover, in the Easy condition, saccade biases to distractors matching VWM content were related with better VWM performance.
Our results indicate that the likelihood of saccade biases is related to the task difficulty and VWM engagement.