Influence of Foggy Weather on Drivers’ Situation Awareness in the Takeover Process of Level 3 Automated Vehicles: A Functional Magnetic Resonance Imaging Study

Abstract

Foggy weather is a prominent contributing factor to the malfunction of Level 3 automated driving systems, potentially impairing drivers’ perception and reaction during the takeover process. While previous studies have investigated fog’s impact on takeover safety by assessing drivers’ visual attention, the influence of fog on drivers’ recovery of situation awareness (SA) during takeovers—particularly concerning neural activities—has been overlooked. This research aims to use functional magnetic resonance imaging (fMRI) to examine how fog affects drivers’ brain activities during takeovers of Level 3 automated driving. Thirty volunteers participated in the experiment. Initially, they engaged in a non-driving-related task. On receiving a takeover request, participants pressed a button, which was followed by the presentation of a driving scenario video. The results showed that fog did not affect brain activation in non-critical takeovers, while significantly influencing brain activation in critical takeovers. Compared with the clear × critical scenario, the percentage change in signal intensity of the middle occipital gyrus and the fusiform gyrus in the foggy × critical scenario was significantly lower. Moreover, the thalamus, prefrontal cortex, and precuneus were activated only in the clear × critical scenario, suggesting that high-level cognitive functions were impeded in foggy weather. These findings indicate that foggy weather impairs drivers’ information perception (Level 1 SA) during takeovers, consequently suppressing comprehension (Level 2 SA) and projection (Level 3 SA). This highlights the potential of fMRI as an effective tool for comprehending drivers’ cognitive states throughout the takeover process.