Exploring the Effects of Traditional Chinese Medicine Scents on Mitigating Driving Fatigue

TL;DR

The paper tackles driving fatigue in autonomous driving contexts by evaluating Traditional Chinese Medicine scents in two driving-simulator studies. Study 1 maps six TCM scents to the arousal–valence circumplex to identify argy wormwood (high arousal) and tangerine peel (high valence) for testing in Study 2, which shows both scents improve alertness and reaction time, with distinct short-term vs. long-term usage profiles. The results demonstrate that TCM scents can mitigate fatigue and improve driving performance, though scent longevity and acceptance differ by scent, prompting ideas for AI-assisted, personalized scent-regulation in cars. These insights could guide the development of in-car fatigue-regulation designs that leverage culturally resonant olfactory cues while acknowledging practical limitations.

Abstract

The rise of autonomous driving technology has led to concerns about inactivity-induced fatigue. This paper explores Traditional Chinese Medicine (TCM) scents for mitigating. Two human-involved studies have been conducted in a high-fidelity driving simulator. Study 1 maps six prevalent TCM scents onto the arousal/valence circumplex to select proper candidates, i.e., argy wormwood (with the highest arousal) and tangerine peel (with the highest valence). Study 2 tests both scents in an auto-driving course. Statistics show both scents can improve driver alertness and reaction-time, but should be used in different ways: argy wormwood is suitable for short-term use due to its higher intensity but poor acceptance, while tangerine peel is ideal for long-term use due to its higher likeness. These findings provide insights for in-car fatigue mitigation to enhance driver safety and well-being. However, issues such as scent longevity as for aromatherapy and automatic fatigue prediction remain unresolved.

Figures (8)

• Figure 1: Our study aims to mitigate driving fatigue with TCM scents. As the left picture shows, autonomous driving can cause driving fatigue easily. Unregulated, it may lead to a car accident. Our research found that tangerine peel regulation can make drivers comfortable and alert, while argy wormwood regulation makes drivers less comfortable but more alert. Both benefit driving safety.
• Figure 2: Material and results of Study 1:(a) shows the ingredients and efficacy of the six TCM scents selected in Study 1. (b) presents the results of Study 1, mapping the TCM scents onto the arousal/valence circumplex.
• Figure 3: The on-site equipment for Study 2: Fig. (a) shows the position of the steering wheel, the buttons of the reaction-time recording program, and the scent release device. Fig. (b) shows the driving simulation scene used throughout Study 2.
• Figure 4: The timeline of the Study 2 procedure. Participants filled out a pre-questionnaire. Then, they drove autonomously for 5min to get used to the simulator. Next, they drove autonomously for 10min to induce fatigue. Then, 3 rounds of scent release experiments were conducted. The round order was randomized. Finally, participants filled out a scent-evaluation questionnaire and had an interview.
• Figure 5: Results of Study 2. (* p < 0.05, ** p < 0.01, *** p < 0.001, all figures follow this annotation)