Assessing the validity of situation awareness measures through visual behaviours in car driving: A comprehensive review

Situation Awareness (SA), encompassing perception, comprehension, and projection of environment is essential for effective driving performance. Traditional SA measurements have important limitations: task interruption, subjectivity, and inability to capture SA's dynamic nature. While unaffected by these limitations, visual behaviours are not traditionally used to measure SA. This review aimed to identify the potential links between SA and visual behaviours in car driving. We identified 22 studies: 15 measured both SA and visual behaviours, and seven additional studies used visual behaviour as a proxy measure of SA. Within the 15 core studies, better SA was correlated with better hazard detection, greater horizontal gaze dispersion, higher saccade frequency and velocity and longer fixation duration. Among these studies, predictive approaches showed that gaze allocation to the road and mirrors, as well as pupillary measures, were among the best predictors of SA. The seven additional studies assessing SA from visual behaviours indicated a positive effect of driving experience and devices (indicating trust in automation or hazard presence) on SA, alongside a negligible impact of short secondary task engagement. We discussed the potential of SA measures based on visual behaviour, acknowledging their limitations while highlighting their promise as real-time, insightful alternatives to traditional SA measurement.