Gavin Woodward¹, Satoshi Shioiri², Chia-Huei Tseng², Hiu Mei Chow¹; ¹St. Thomas University, Fredericton, Canada, ²Research Institute of Electrical Communication, Tohoku University, Sendai, Japan

Observers often fail to detect the displacement of objects during saccades—a phenomenon termed saccadic suppression of displacement (SSD). Interestingly, SSD is reduced when a brief gap occurs in a sound presented alongside the saccade target, resulting in improved displacement discrimination (auditory blanking effect; Chow et al., 2025 VSS). The auditory blanking effect suggests that sounds are weighed in visual stability judgements, but how is not yet known. We evaluated one possible mechanism: that the sound is bound with the visual target, such that auditory blanking indicates a change in the visual target. Given that such binding is most likely to occur when multimodal stimuli are aligned in time, we hypothesize that reducing temporal synchrony between the sound and visual target should reduce the auditory blanking effect. Twenty participants made saccades (18°) toward visual targets that were presented alongside a sound, either synchronously or asynchronously (with a 150 ms lead for the sound). Once the participants’ saccade was detected, the visual target was displaced to the left or right (0.33°) and participants were tasked to report the direction of displacement. Critically, to test the auditory blanking effect, the sound was paused for 100 ms upon saccade detection (auditory gap) in half the trials and was continuous (no gap) in the other half. Results showed that the auditory gap improved participants’ displacement discrimination (d’ = 0.47), compared to no gap (d’ = 0.31; p = .038, η2 = .031), successfully replicating the auditory blanking effect. However, manipulating the temporal synchrony of the visual target and sound did not influence the size of the auditory blanking effect (p = .266, η2 = .007). The latter finding does not support the notion that multisensory integration is necessary for the auditory blanking effect to occur, suggesting the need for further investigation into alternative explanations.

Acknowledgements: This work was carried out under the Discovery Grant Program of the Natural Sciences and Engineering Research Council of Canada (RGPIN-2024-06028) and the Cooperative Research Project Program of the Research Institute of Electrical Communication, Tohoku University (R05/A17).