Changes in operators' perceived situation awareness during multitask performance under ship motion conditions.

This study examined how ship motion affects operators' perceived situation awareness during multitask execution. Thirty male participants performed the Multi-Attribute Task Battery under different ship motion intensities. Perceived situation awareness, perceived workload, task performance, and eye movements were recorded. As motion intensity increased, SART scores and situation understanding declined, while attentional demand increased. Eye movements showed smaller saccade amplitudes and larger pupil diameters, suggesting a narrowed visual scanning range and higher workload. Task effects varied by integration level: monitoring remained relatively stable, tracking was highly sensitive to motion, and communications and resource management showed greater degradation despite increased visual attention. Participants with lower performance stability showed greater reductions in perceived situation awareness and less stable attentional regulation. These findings suggest ship motion may be linked to reduced perceived situation awareness, potentially via cognitive competition from postural control and gaze stabilisation, while unstable visual input constrains information updating and cross-source integration.