## 3 Analysis of Current Knowledge
### Applications of the Eye Tracking Method  
Studies of drivers' behavior can show how drivers are distracted by advertising devices. The study can use eye tracking, which is applicable while driving in real traffic and the test subject is directly affected by the external environment. Eye tracking is a measurement in which either the relative movement of the eye to the head or the direct point of view of the subject is recorded using an eye tracker. Studies often focus on how often and for how long drivers watch certain types of devices near the road. They have been shown to look more often and longer at dynamic advertising devices [3]. Based on this conclusion, a study was conducted on the impact of moving images on traffic safety. The eye movements of several drivers were observed while they drove through intersections both with and without dynamic advertising devices. The investigation showed that drivers did not look less at traffic signs when dynamic advertising devices were around, but that some drivers drove unsafely while looking at dynamic advertising devices [24]. Regarding the number and duration of gaze fixation on the selected advertisements, for example, in the study [25], no driver was found to have a gaze fixation time longer than 1 s. Other studies have compared drivers' behavior in the presence and absence of advertising devices. A study [26], which monitored driver behavior on a driving simulator, showed that when advertising areas are placed close to the road, drivers spend less time observing what is happening on the road. Another simulator study [27] concluded that advertising devices close to a road are more likely to distract the driver's gaze from what is happening on the road, but always \"only for a short period of time\". However, this statement can be very misleading, as it is this'short time' that can influence the delay in the initiation of braking. The same study also showed that after the test, subjects were more likely to remember the last advertising message than the last road sign. This premise is somewhat consistent with the findings of a study [28] that showed that drivers respond more slowly to traffic signs when influenced by advertising devices. It is known that moving objects as well as objects that appear unexpectedly or objects with large brightness variability are very difficult to ignore while driving (see for example [29; 30; 31]). Research in this area generally agrees that moving advertisements near the roads affect drivers' attention more significantly than static ones. For example, one study [32], which tested driver behavior directly in real traffic, found that drivers look at moving advertisements more often and for longer periods of time than at static ones. They reached identical conclusions by comparing static and moving advertisements in a simulator study [33]. It can also be inferred from this work that drivers deviated from the direction of travel more frequently and drove more slowly in the presence of moving advertisements than in the presence of static ones. Finally, the study shows that in the presence of moving advertisements, drivers are more likely to brake at the last moment (e.g., before a pedestrian crossing). In contrast, a study [24] in Toronto found that moving advertisements did not substantially reduce drivers' perception of traffic signs. However, the moving nature of the advertising messages increased the duration of the viewing area (1.5 s) and led to a reduction in the distance between cars (1 s or less). The intensity of the driver's attention is significantly related to the question of advertising device positioning. Devices located in the central field of view are more likely to catch the driver's attention than those in the periphery [33], and devices located at eye level are more likely to catch the driver's attention than those located higher up [28]. The Swedish Transport Administration has approved the trial installation of twelve LED advertising devices near a three-lane highway through the center of Stockholm.