# Review of Studies on User Research Based on EEG and Eye Tracking
## 4 Application Scope
### Spatial Environment
#### 4.3.2 Transportation System  
In the transportation system, eye-tracking technology is currently widely used to finely measure people's perception, emotions, and behavior, which provide strong support for establishing the relationship between the characteristics of complex road environments and the psychological and physiological indicators of drivers. It has been widely used in the research of traffic systems such as signal lights, routes and signs, and isolation belts. For example, [PERSON] et al. [83] proved through experiments that tunnel brightness has a significant impact on indicators such as drivers' gaze duration, scanning range, and blink frequency. [PERSON] et al. [84] studied the distribution law of drivers' gaze points under different channel width conditions. [PERSON] et al. [85] explored the effects of three types of road environments--open, forest-covered, and diverse--on driving behavior. [PERSON] et al. [86] started from the perspective of visual interest areas, and studied the relationship between the information volume of interest areas set by drivers for traffic engineering facilities in highways and drivers' visual characteristics. [PERSON] et al. [87] conducted a study to explore the cognitive implications of different background colors in traffic signs. The results showed that early-stage event-related potentials (ERPs), specifically the N1 and P2 components, exhibited similar patterns across various background colors of incorrect traffic signs, suggesting minimal influence on cognitive processing. However, blue and green background colors elicited larger P300 amplitudes during later stages, indicating heightened cognitive processing difficulty. In a separate investigation by [PERSON] et al. [88], it was discovered that semantically incongruent traffic sign words evoked greater N400 amplitudes and theta activity, whereas semantically congruent traffic sign words evoked stronger late positive potentials, reflecting participants' positive emotional arousal. These findings have significant implications for assessing the impact of color, semantics, and design on the comprehension of traffic signs, and on the overall understanding of environmental contexts.  
[PERSON] [89] systematically explored the effects of a linear spatial layout of a central divider on driving behavior in urban expressways, and analyzed changes in various characteristic parameters under different visual stimuli of the central divider layout. The results show that the focus at a speed of 70 km/h was found to be more concentrated towards the middle of the road than the focus at a speed of 50 km/h. According to visual characteristics, a natural layout form can not only improve the monotony of an urban expressway landscape environment, but also provide appropriate visual stimulation. In comparison to a disorganized environment, an organized environment evokes greater amplitudes of the N2 component, which is linked to cognitive processing conflicts [90]. It provides a certain theoretical basis for improving the traffic layout of central dividers, and improving driving safety.  
In addition, in the quantitative research of traffic landscape spaces, the research method of multi-source visual data fusion combined with spatiotemporal measurement has been widely used, and provides strong support for the study of the impact of road environments on drivers' visual stimulation. For example, the concept of visual entropy was introduced to measure the size of image information and the sensitivity of the human visual system to images [91]. [PERSON] et al. [92] used gaze entropy as an important predictive indicator of workload. [PERSON] et al. [93] determined the threshold values for discriminating fatigue driving behavior indicators under different road line shapes, and established a comprehensive fatigue driving discrimination model based on various driving behavior indicators and threshold values. These application studies provide a basis for improving and ensuring the safety of urban road traffic systems.