Research on the relationship between drivers' fixation behavior and road cognitive efficiency in curved tunnel environments.

Objectives: This study aims to explore the relationship between drivers' fixation behavior and road cognitive efficiency in curved tunnel environments. The objective is to understand how factors such as tunnel radius, turning direction, and tunnel zones influence drivers' visual behaviors and cognitive processes.

Methods: The research involves 30 participants and utilizes eye tracking technology to collect data. Data are gathered in 4 curved tunnels located in Yunnan Province. Participants' fixation duration, frequency, and horizontal and vertical deviations are measured and analyzed.

Results: The study finds that the radius, turning direction, and zones of curved tunnels significantly affect drivers' visual behaviors. Smaller tunnel radius leads to increased fixation duration and decreased frequency of visual scanning. Drivers exhibit decreased horizontal deviation, indicating a more focused visual search strategy, and increased vertical deviation, possibly as an adaptive strategy to broaden the vertical field of view. During left turns, drivers have longer fixation durations and lower frequencies due to right hemisphere dominance in processing spatial information, resulting in increased cognitive load. Differences in deviations are observed between left and right turns, reflecting distinct visual scanning patterns. In different tunnel zones, drivers demonstrate varied strategies: In the entrance zone, longer fixations and smaller horizontal deviations occur; in the middle zone, shorter fixations and increased frequency are observed; and in the exit zone, the highest fixation frequency and horizontal deviation are noted.

Conclusions: The conclusions emphasize that the geometry and characteristics of curved tunnels play a crucial role in shaping drivers' visual behaviors and cognitive processes. Understanding these relationships is essential for enhancing tunnel design and improving driving safety. This research provides valuable insights for optimizing tunnel design to better meet drivers' needs and for implementing appropriate safety measures, ultimately contributing to the reduction of accidents and an enhancement of overall road safety in curved tunnel environments.