The influence of lighting environment in extra-long tunnels and its psychological impact on young drivers: evidence from virtual driving simulations.

Purpose: The monotonous lighting environment in extra-long tunnels often induces mind-wandering in drivers. To address this issue, this study explores effective strategies to optimize tunnel lighting environments by configuring various background colors and special lighting zones to enhance the alertness of young drivers and ensure driving safety.

Methods: A virtual driving simulator was utilized to carry out the experiment. By integrating heart rate variability (HRV) indicators with facial expression analysis technology, this study systematically investigates the effects of three background lighting colors-red, blue, and yellow (with a luminance range of 30.5-39.6 cd/m²)-under single-zone and two-zone special lighting stimulation conditions. A non-contact "physiology-behavior" coupling evaluation model based on the XGBoost algorithm is developed to enable real-time monitoring of the mind-wandering levels of young drivers (K-values), providing an alternative to traditional electrode-based detection methods.

Results: Two-zone special lighting stimulation significantly improved driver alertness and arousal compared to single-zone stimulation. Under red background lighting with two-zone stimulation, the LF/HF ratio decreased by 32.6% (p < 0.05), and a continuous decline in neutral facial expression scores indicated a sustained alerting effect. In contrast, blue background lighting demonstrated the best performance under single-zone stimulation, reducing the LF/HF ratio by 8.39% and suggesting a short-term stress-relief advantage.

Conclusion: This virtual driving simulation study revealed that red and blue background lighting exert distinct effects on mind-wandering regulation. Red light with two-zone stimulation effectively suppressed mind-wandering over time, while blue light with single-zone stimulation provided rapid physiological stress relief. In addition, a heart rate-neutral emotion coupling model was constructed, enabling non-contact mind-wandering assessment through facial expression analysis, thereby simplifying the monitoring process.