Visual working memory-related saccade biases are amplified by task demands, without updating working memory content

Visual working memory (VWM) and oculomotor control exert bi-directional influences on each other: eye movements during memory delays can influence VWM performance, and VWM content can bias the execution of eye movements. Oculomotor capture has been shown to extend to automatic, corrective saccades that can be biased towards distractors whose feature matches VWM content. We address the question of bi-directional influences between VWM and the oculomotor system, here with a focus on corrective saccade biases. 20 participants had to memorize a color hue and later discriminate it from another hue from a different (Easy condition) or the same color category (Difficult condition). Between encoding and test, they performed a gaze-contingent saccade task where, mid-saccade, the position of items shifted, introducing an artificial saccade error, and the color of a distractor neighboring the target changed to a color (mis)matching the memorized one. VWM performance was higher in the Easy compared to the Difficult experimental block, reflecting the successful manipulation of task demands. Corrective saccade biases towards the distractor occurred more frequently when it matched memory content compared to when it did not, replicating previous findings. Importantly, they also occurred more in the Difficult experimental block, which required stronger VWM representations than the Easy condition. VWM performance, however, was not affected by saccade corrections to memory (mis)matching distractors. Our results provided no evidence of saccade biases having a role in the updating of VWM content, however they indicate an influence of task demands and VWM engagement on automatic oculomotor biases.